1996
Donaldson, K E; Carpenter, W H; Toth, M J; Goran, M I; Newhouse, P; Poehlman, E T
No evidence for a higher resting metabolic rate in noninstitutionalized Alzheimer's disease patients Journal Article
In: J Am Geriatr Soc, 44 (10), pp. 1232–1234, 1996.
@article{pmid8856004,
title = {No evidence for a higher resting metabolic rate in noninstitutionalized Alzheimer's disease patients},
author = {K E Donaldson and W H Carpenter and M J Toth and M I Goran and P Newhouse and E T Poehlman},
year = {1996},
date = {1996-00-01},
journal = {J Am Geriatr Soc},
volume = {44},
number = {10},
pages = {1232--1234},
abstract = {It has previously been suggested that Alzheimer's disease patients have higher resting energy requirements than healthy individuals, which may contribute to their unexplained weight loss. We examined whether resting metabolic rate, the largest component of daily energy expenditure, is elevated in Alzheimer's patients compared with healthy older controls. Cross-sectional. General Clinical Research Center and Baltimore VA Medical Center. Twenty-five noninstitutionalized demented patients (74 +/- 8 years; mean +/- SD) with a wide range of Mini-Mental Examination scores (1 to 20) and 73 healthy older individuals (69 +/- 7 years). Resting metabolic rate was measured by indirect calorimetry, fat-free mass and fat mass by dual energy X-ray absorptiometry, and daily energy intake by food diaries. No differences in fat-free mass and fat mass were noted between Alzheimer's disease patients and healthy older controls. Resting metabolic rate was similar in Alzheimer's disease patients (5446 +/- 962 kJ/day) and healthy older individuals (5647 +/- 887 kJ/day). These results persisted when resting metabolic rate was statistically adjusted for differences in body composition and age. These results provide no evidence for an elevation in resting energy requirements in noninstitutionalized demented patients.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
It has previously been suggested that Alzheimer's disease patients have higher resting energy requirements than healthy individuals, which may contribute to their unexplained weight loss. We examined whether resting metabolic rate, the largest component of daily energy expenditure, is elevated in Alzheimer's patients compared with healthy older controls. Cross-sectional. General Clinical Research Center and Baltimore VA Medical Center. Twenty-five noninstitutionalized demented patients (74 +/- 8 years; mean +/- SD) with a wide range of Mini-Mental Examination scores (1 to 20) and 73 healthy older individuals (69 +/- 7 years). Resting metabolic rate was measured by indirect calorimetry, fat-free mass and fat mass by dual energy X-ray absorptiometry, and daily energy intake by food diaries. No differences in fat-free mass and fat mass were noted between Alzheimer's disease patients and healthy older controls. Resting metabolic rate was similar in Alzheimer's disease patients (5446 +/- 962 kJ/day) and healthy older individuals (5647 +/- 887 kJ/day). These results persisted when resting metabolic rate was statistically adjusted for differences in body composition and age. These results provide no evidence for an elevation in resting energy requirements in noninstitutionalized demented patients.
Figueroa-Colon, R; Franklin, F A; Goran, M I; Lee, J Y; Weinsier, R L
Reproducibility of measurement of resting energy expenditure in prepubertal girls Journal Article
In: Am. J. Clin. Nutr., 64 (4), pp. 533–536, 1996.
@article{pmid8839496,
title = {Reproducibility of measurement of resting energy expenditure in prepubertal girls},
author = {R Figueroa-Colon and F A Franklin and M I Goran and J Y Lee and R L Weinsier},
year = {1996},
date = {1996-00-01},
journal = {Am. J. Clin. Nutr.},
volume = {64},
number = {4},
pages = {533--536},
abstract = {We determined the reproducibility of measuring resting energy expenditure (REE) and the effect on REE of spending the night before testing at home compared with in a clinical research center. We studied 19 prepubertal girls aged 6.0-10.1 y with a mean weight-for-height of 108% of ideal. REE was measured for 30 min with a metabolic monitor after 12 h of fasting on three consecutive mornings during two different hospitalizations 6 wk apart. The initial REE measurement of each hospitalization was obtained on admission and the second and third measurements were performed during the 3-d hospitalization. Energy intake was ad libitum and was recorded while the children were in the research center. Body composition was determined twice with dual-energy X-ray absorptiometry. No significant effect on REE of day within visit was found across visits. There was no significant difference between the initial REE measurement and the second and third measurements. The mean REEs for the two hospitalizations were highly correlated. The mean CV in intraindividual REE (ie, all six measurements) was 5.8% and was unchanged when adjusted for fat-free body mass (FFM) or body weight. The mean CV in interindividual REE decreased when adjusted for FFM or body weight. Because REE was highly reproducible, a single measurement can suffice for energy expenditure studies in girls aged 6-10 y. Admission to a clinical research setting is not necessary for a reliable determination of REE.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We determined the reproducibility of measuring resting energy expenditure (REE) and the effect on REE of spending the night before testing at home compared with in a clinical research center. We studied 19 prepubertal girls aged 6.0-10.1 y with a mean weight-for-height of 108% of ideal. REE was measured for 30 min with a metabolic monitor after 12 h of fasting on three consecutive mornings during two different hospitalizations 6 wk apart. The initial REE measurement of each hospitalization was obtained on admission and the second and third measurements were performed during the 3-d hospitalization. Energy intake was ad libitum and was recorded while the children were in the research center. Body composition was determined twice with dual-energy X-ray absorptiometry. No significant effect on REE of day within visit was found across visits. There was no significant difference between the initial REE measurement and the second and third measurements. The mean REEs for the two hospitalizations were highly correlated. The mean CV in intraindividual REE (ie, all six measurements) was 5.8% and was unchanged when adjusted for fat-free body mass (FFM) or body weight. The mean CV in interindividual REE decreased when adjusted for FFM or body weight. Because REE was highly reproducible, a single measurement can suffice for energy expenditure studies in girls aged 6-10 y. Admission to a clinical research setting is not necessary for a reliable determination of REE.
1995
Goran, M I; Khaled, M A
Cross-validation of fat-free mass estimated from body density against bioelectrical resistance: effects of obesity and gender Journal Article
In: Obes. Res., 3 (6), pp. 531–539, 1995.
@article{pmid8653529,
title = {Cross-validation of fat-free mass estimated from body density against bioelectrical resistance: effects of obesity and gender},
author = {M I Goran and M A Khaled},
year = {1995},
date = {1995-11-01},
journal = {Obes. Res.},
volume = {3},
number = {6},
pages = {531--539},
abstract = {The major purpose of this study was to examine whether estimates of body composition from bioelectrical resistance were systematically biased by obesity and/or gender (using hydrodensitometry as a comparison method). We compared fat-free mass (FFM) by bioelectrical resistance (BR) using 5 equations (Lukaski, Kushner, Rising, Khaled, and Segal) to FFM by hydrodensitometry (HD) in 20 lean men, 30 lean women, 33 obese men and 22 obese women. None of the BR equations was successfully cross-validated against FFM by HD in all 4 sub-groups. The Lukaski equation significantly underestimated FFM in all 4 groups by 2.7 to 4.7 kg; the Kushner equation significantly underestimated FFM by 2.0 to 2.9 kg except in obese women; the Rising equation significantly overestimated FFM in obese women (5.3 kg) and men (2.9 kg); the Khaled equation successfully predicted FFM in all groups except obese men; and the Segal equation successfully predicted FFM in all groups except lean men. In some groups, a portion of the discrepancy could be explained by bias originating from body fat. Analysis of our data by forward regression analysis demonstrated that height2/resistance, body weight, gender and suprailiac skinfold thickness provide the most accurate estimates of FFM (R2 = 0.92; SEE = 3.58 kg) that are free of bias originating from gender and body fat. We conclude that the estimation of fat-free mass by BR is significantly influenced by gender and obesity. An alternative equation is proposed for estimating fat-free mass based on measurement of height2/resistance, body weight, gender and suprailiac skinfold thickness.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The major purpose of this study was to examine whether estimates of body composition from bioelectrical resistance were systematically biased by obesity and/or gender (using hydrodensitometry as a comparison method). We compared fat-free mass (FFM) by bioelectrical resistance (BR) using 5 equations (Lukaski, Kushner, Rising, Khaled, and Segal) to FFM by hydrodensitometry (HD) in 20 lean men, 30 lean women, 33 obese men and 22 obese women. None of the BR equations was successfully cross-validated against FFM by HD in all 4 sub-groups. The Lukaski equation significantly underestimated FFM in all 4 groups by 2.7 to 4.7 kg; the Kushner equation significantly underestimated FFM by 2.0 to 2.9 kg except in obese women; the Rising equation significantly overestimated FFM in obese women (5.3 kg) and men (2.9 kg); the Khaled equation successfully predicted FFM in all groups except obese men; and the Segal equation successfully predicted FFM in all groups except lean men. In some groups, a portion of the discrepancy could be explained by bias originating from body fat. Analysis of our data by forward regression analysis demonstrated that height2/resistance, body weight, gender and suprailiac skinfold thickness provide the most accurate estimates of FFM (R2 = 0.92; SEE = 3.58 kg) that are free of bias originating from gender and body fat. We conclude that the estimation of fat-free mass by BR is significantly influenced by gender and obesity. An alternative equation is proposed for estimating fat-free mass based on measurement of height2/resistance, body weight, gender and suprailiac skinfold thickness.
Statistical considerations regarding the use of ratios to adjust data Journal Article
In: Int. J. Obes. Relat. Metab. Disord., 19 (9), pp. 644–652, 1995.
@article{pmid8574275,
title = {Statistical considerations regarding the use of ratios to adjust data},
year = {1995},
date = {1995-09-01},
journal = {Int. J. Obes. Relat. Metab. Disord.},
volume = {19},
number = {9},
pages = {644--652},
abstract = {The use of ratios to adjust data (i.e. índex' variables) is common in obesity and related research. The rationale for the use of ratios often seems to be the desire to control or eliminate the influence of the variable in the denominator. The purpose of this paper is to gain a greater appreciation of the statistical assumptions underlying ratios and their impact on data interpretation. We demonstrate the limitations of the indiscriminant use of ratios to adjust data. Specifically, we show that: (1) given linearity, a zero intercept between the numerator and denominator are necessary and sufficient conditions for a ratio to remove the confounding effects of the denominator; (2) seemingly minor departures from a zero intercept can have major consequences on the ratio's ability to control for the denominator; (3) the ratio of two normally distributed variables cannot be normally distributed, and this may violate the assumptions of subsequent parametric statistical analyses; (4) the use of ratios affects the error distribution of the data which may also violate the assumptions of subsequent parametric statistical analyses; (5) the use of ratios cannot easily take nonlinear effects between the numerator and denominator into account; (6) the use of ratios can introduce spurious correlations among the ratios and other variables; (7) the use of ratios can create interpretive difficulties. We also clarify that the mean of ratios is not necessarily equivalent to the ratio of the means of the numerator and denominator. Finally, we present and discuss formulae for the reliability of ratios and residuals. Because of the above issues, we question the indiscriminant use of ratios and advocate that investigators consider regression-based approaches as alternatives.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The use of ratios to adjust data (i.e. índex' variables) is common in obesity and related research. The rationale for the use of ratios often seems to be the desire to control or eliminate the influence of the variable in the denominator. The purpose of this paper is to gain a greater appreciation of the statistical assumptions underlying ratios and their impact on data interpretation. We demonstrate the limitations of the indiscriminant use of ratios to adjust data. Specifically, we show that: (1) given linearity, a zero intercept between the numerator and denominator are necessary and sufficient conditions for a ratio to remove the confounding effects of the denominator; (2) seemingly minor departures from a zero intercept can have major consequences on the ratio's ability to control for the denominator; (3) the ratio of two normally distributed variables cannot be normally distributed, and this may violate the assumptions of subsequent parametric statistical analyses; (4) the use of ratios affects the error distribution of the data which may also violate the assumptions of subsequent parametric statistical analyses; (5) the use of ratios cannot easily take nonlinear effects between the numerator and denominator into account; (6) the use of ratios can introduce spurious correlations among the ratios and other variables; (7) the use of ratios can create interpretive difficulties. We also clarify that the mean of ratios is not necessarily equivalent to the ratio of the means of the numerator and denominator. Finally, we present and discuss formulae for the reliability of ratios and residuals. Because of the above issues, we question the indiscriminant use of ratios and advocate that investigators consider regression-based approaches as alternatives.
Goran, M I; Allison, D B; Poehlman, E T
Issues relating to normalization of body fat content in men and women Journal Article
In: Int. J. Obes. Relat. Metab. Disord., 19 (9), pp. 638–643, 1995.
@article{pmid8574274,
title = {Issues relating to normalization of body fat content in men and women},
author = {M I Goran and D B Allison and E T Poehlman},
year = {1995},
date = {1995-09-01},
journal = {Int. J. Obes. Relat. Metab. Disord.},
volume = {19},
number = {9},
pages = {638--643},
abstract = {Body mass index (BMI), % body fat, and the fat:lean ratio are ratios frequently used as obesity indices. Ratios are based on an assumption that the regression between the numerator (e.g. fat mass) and the denominator (e.g. body mass) has a zero-intercept. As shown in the companion paper, non-zero intercepts cause several problems when ratios are used to adjust data and analysis of covariance (ANCOVA) is frequently the preferred statistical tool. The purpose of this paper is to examine whether BMI, % body fat and the fat:lean ratio meet the necessary criteria for suitable obesity indices using gender comparisons as an example. In 720 healthy men and women, BMI was higher in men (24.9 +/- 3.3 vs 23.4 +/- 3.2 kg/m2, P < 0.001), but fat mass, % fat and the fat:lean ratio were higher in women (14.8 +/- 8.4 vs 19.1 +/- 8.1 kg fat; 18.6 +/- 8.7 vs 29.9 +/- 9.7% body fat; 0.24 +/- 0.14 vs 0.46 +/- 0.20 for the fat:lean ratio; P < 0.001). Body mass (BM) was correlated with height2 in men (r = 0.40) and women (r = 0.36) with equivalent regression slopes (17.1 +/- 1.9 vs 15.6 +/- 2.3 kg per m2 in women), but the intercepts were different from zero (24.1 kg in men, 20.7 kg in women). When BM was adjusted for height2 using ANCOVA, men remained significantly heavier than women (74.4 +/- 11.0 vs 68.8 +/- 11.6 kg; P < 0.001). Fat mass (FM) was significantly correlated with BM in males (r = 0.64) and females (r = 0.78) but the regression slopes were different (0.49 +/- 0.03 vs 0.71 +/- 0.03 kg of fat per kg body mass in females; P < 0.05) and the intercepts were different from zero (-23.2 +/- 2.2 kg in males; -24.8 +/- 2.1 kg in females). FM adjusted for BM was significantly higher in women (11.7 vs 25.6 kg). FM was inversely correlated with fat free mass (FFM) in males (r = -0.17) and females (r = -0.20), with similar regression slopes (-0.16 +/- 0.05 vs -0.26 +/- 0.08 kg of FM per kg of FFM in women) and the intercepts were significantly different from zero (24.8 +/- 3.0 kg in males; 30.7 +/- 3.6 kg in females). When FM was adjusted for FFM, there was no significant difference between men (16.3 kg) and women (17.0 kg). It is concluded that: (a) the presence of significant intercepts does not support the use of ratios as obesity indices and regression based models should be considered; and, (b) the direction and magnitude of the difference in obesity index between men and women changes with different normalization approaches.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Body mass index (BMI), % body fat, and the fat:lean ratio are ratios frequently used as obesity indices. Ratios are based on an assumption that the regression between the numerator (e.g. fat mass) and the denominator (e.g. body mass) has a zero-intercept. As shown in the companion paper, non-zero intercepts cause several problems when ratios are used to adjust data and analysis of covariance (ANCOVA) is frequently the preferred statistical tool. The purpose of this paper is to examine whether BMI, % body fat and the fat:lean ratio meet the necessary criteria for suitable obesity indices using gender comparisons as an example. In 720 healthy men and women, BMI was higher in men (24.9 +/- 3.3 vs 23.4 +/- 3.2 kg/m2, P < 0.001), but fat mass, % fat and the fat:lean ratio were higher in women (14.8 +/- 8.4 vs 19.1 +/- 8.1 kg fat; 18.6 +/- 8.7 vs 29.9 +/- 9.7% body fat; 0.24 +/- 0.14 vs 0.46 +/- 0.20 for the fat:lean ratio; P < 0.001). Body mass (BM) was correlated with height2 in men (r = 0.40) and women (r = 0.36) with equivalent regression slopes (17.1 +/- 1.9 vs 15.6 +/- 2.3 kg per m2 in women), but the intercepts were different from zero (24.1 kg in men, 20.7 kg in women). When BM was adjusted for height2 using ANCOVA, men remained significantly heavier than women (74.4 +/- 11.0 vs 68.8 +/- 11.6 kg; P < 0.001). Fat mass (FM) was significantly correlated with BM in males (r = 0.64) and females (r = 0.78) but the regression slopes were different (0.49 +/- 0.03 vs 0.71 +/- 0.03 kg of fat per kg body mass in females; P < 0.05) and the intercepts were different from zero (-23.2 +/- 2.2 kg in males; -24.8 +/- 2.1 kg in females). FM adjusted for BM was significantly higher in women (11.7 vs 25.6 kg). FM was inversely correlated with fat free mass (FFM) in males (r = -0.17) and females (r = -0.20), with similar regression slopes (-0.16 +/- 0.05 vs -0.26 +/- 0.08 kg of FM per kg of FFM in women) and the intercepts were significantly different from zero (24.8 +/- 3.0 kg in males; 30.7 +/- 3.6 kg in females). When FM was adjusted for FFM, there was no significant difference between men (16.3 kg) and women (17.0 kg). It is concluded that: (a) the presence of significant intercepts does not support the use of ratios as obesity indices and regression based models should be considered; and, (b) the direction and magnitude of the difference in obesity index between men and women changes with different normalization approaches.
Goran, M I; Carpenter, W H; McGloin, A; Johnson, R; Hardin, J M; Weinsier, R L
Energy expenditure in children of lean and obese parents Journal Article
In: Am. J. Physiol., 268 (5 Pt 1), pp. E917–924, 1995.
@article{pmid7762646,
title = {Energy expenditure in children of lean and obese parents},
author = {M I Goran and W H Carpenter and A McGloin and R Johnson and J M Hardin and R L Weinsier},
year = {1995},
date = {1995-05-01},
journal = {Am. J. Physiol.},
volume = {268},
number = {5 Pt 1},
pages = {E917--924},
abstract = {We evaluated whether children of obese parents have defects in energy expenditure in a study of 73 children (5 +/- 0.9 yr of age) of lean and obese parents. Total energy expenditure (TEE) was measured over 14 days by use of doubly labeled water and physical activity energy expenditure (AEE) derived by subtracting resting energy expenditure (REE) under postprandial conditions. Fat and fat-free mass (FFM) were measured in children and parents with use of bioelectrical resistance. There were no significant correlations between TEE, REE, or AEE in children (after adjustment for FFM) and body fat in children or body fat in mothers or fathers. In three-way analysis of covariance (ANCOVA, with FFM as a covariate), there were no significant effects of gender in children, obesity in mothers, or obesity in fathers on TEE or AEE in children. There was a significant effect of gender and a significant interaction between obesity in mothers and obesity in fathers on REE; relative to children with two nonobese or two obese parents, REE was approximately 6% lower in children when mothers only or fathers only were obese. In conclusion, our data do not support the hypothesis that children of obese parents have major defects in energy expenditure.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We evaluated whether children of obese parents have defects in energy expenditure in a study of 73 children (5 +/- 0.9 yr of age) of lean and obese parents. Total energy expenditure (TEE) was measured over 14 days by use of doubly labeled water and physical activity energy expenditure (AEE) derived by subtracting resting energy expenditure (REE) under postprandial conditions. Fat and fat-free mass (FFM) were measured in children and parents with use of bioelectrical resistance. There were no significant correlations between TEE, REE, or AEE in children (after adjustment for FFM) and body fat in children or body fat in mothers or fathers. In three-way analysis of covariance (ANCOVA, with FFM as a covariate), there were no significant effects of gender in children, obesity in mothers, or obesity in fathers on TEE or AEE in children. There was a significant effect of gender and a significant interaction between obesity in mothers and obesity in fathers on REE; relative to children with two nonobese or two obese parents, REE was approximately 6% lower in children when mothers only or fathers only were obese. In conclusion, our data do not support the hypothesis that children of obese parents have major defects in energy expenditure.
Goran, M I; Figueroa, R; McGloin, A; Nguyen, V; Treuth, M S; Nagy, T R
Obesity in children: recent advances in energy metabolism and body composition Journal Article
In: Obes. Res., 3 (3), pp. 277–289, 1995.
@article{pmid7627777,
title = {Obesity in children: recent advances in energy metabolism and body composition},
author = {M I Goran and R Figueroa and A McGloin and V Nguyen and M S Treuth and T R Nagy},
year = {1995},
date = {1995-05-01},
journal = {Obes. Res.},
volume = {3},
number = {3},
pages = {277--289},
abstract = {In this paper we review recent advances in energy metabolism and body composition studies in prepubescent children and the relationship to childhood obesity. Our review on energy expenditure focusses on studies of total energy expenditure using doubly labeled water, the role of energy expenditure in the development of obesity, and the determinants of resting energy expenditure in children. The relatively few studies that have examined the regulation of energy and macronutrient intake in children are also reviewed. In terms of body composition, we focus on recent methodological studies that have developed existing techniques for application to the pediatric population, including dual energy X-ray absorptiometry and bioelectrical resistance. Lastly, we review existing information relating to measurement and alteration of body fat distribution in children.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this paper we review recent advances in energy metabolism and body composition studies in prepubescent children and the relationship to childhood obesity. Our review on energy expenditure focusses on studies of total energy expenditure using doubly labeled water, the role of energy expenditure in the development of obesity, and the determinants of resting energy expenditure in children. The relatively few studies that have examined the regulation of energy and macronutrient intake in children are also reviewed. In terms of body composition, we focus on recent methodological studies that have developed existing techniques for application to the pediatric population, including dual energy X-ray absorptiometry and bioelectrical resistance. Lastly, we review existing information relating to measurement and alteration of body fat distribution in children.
Poehlman, E T; Gardner, A W; Goran, M I; Arciero, P J; Toth, M J; Ades, P A; Calles-Escandon, J
Sympathetic nervous system activity, body fatness, and body fat distribution in younger and older males Journal Article
In: J. Appl. Physiol., 78 (3), pp. 802–806, 1995.
@article{pmid7775321,
title = {Sympathetic nervous system activity, body fatness, and body fat distribution in younger and older males},
author = {E T Poehlman and A W Gardner and M I Goran and P J Arciero and M J Toth and P A Ades and J Calles-Escandon},
year = {1995},
date = {1995-03-01},
journal = {J. Appl. Physiol.},
volume = {78},
number = {3},
pages = {802--806},
abstract = {It was hypothesized that an increase in total and central body fatness is related to higher sympathetic nervous system activity (SNSA) in older men. Resting SNSA was measured from norepinephrine (NE) kinetics in 69 younger (18-36 yr) and 69 healthy older men (55-80 yr). Body fat distribution was estimated from the waist circumference, body composition from underwater weighing, peak oxygen consumption from a treadmill test to exhaustion, and dietary intake from food diaries. Plasma NE concentrations were 41% higher (P < 0.001) in older men due to a 27% increase (P < 0.001) in NE appearance rate and a tendency for a lower NE clearance rate (P = 0.08). NE appearance rate was higher in individuals of both age groups who exhibited a greater waist circumference and body fatness (range of r values 0.49-0.69; P < 0.01). The waist circumference, and not age, was the strongest predictor of the increase in NE appearance rate in older men. Statistically controlling for the waist circumference or body fatness diminished age-related differences in NE concentrations and in NE appearance rate. These findings suggest that an accumulation of total and central body fat is associated with higher levels of SNSA in older males.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
It was hypothesized that an increase in total and central body fatness is related to higher sympathetic nervous system activity (SNSA) in older men. Resting SNSA was measured from norepinephrine (NE) kinetics in 69 younger (18-36 yr) and 69 healthy older men (55-80 yr). Body fat distribution was estimated from the waist circumference, body composition from underwater weighing, peak oxygen consumption from a treadmill test to exhaustion, and dietary intake from food diaries. Plasma NE concentrations were 41% higher (P < 0.001) in older men due to a 27% increase (P < 0.001) in NE appearance rate and a tendency for a lower NE clearance rate (P = 0.08). NE appearance rate was higher in individuals of both age groups who exhibited a greater waist circumference and body fatness (range of r values 0.49-0.69; P < 0.01). The waist circumference, and not age, was the strongest predictor of the increase in NE appearance rate in older men. Statistically controlling for the waist circumference or body fatness diminished age-related differences in NE concentrations and in NE appearance rate. These findings suggest that an accumulation of total and central body fat is associated with higher levels of SNSA in older males.
Goran, M I
Variation in total energy expenditure in humans Journal Article
In: Obes. Res., 3 Suppl 1 , pp. 59–66, 1995.
@article{pmid7736291,
title = {Variation in total energy expenditure in humans},
author = {M I Goran},
year = {1995},
date = {1995-03-01},
journal = {Obes. Res.},
volume = {3 Suppl 1},
pages = {59--66},
abstract = {The purpose of this paper is to review current data regarding the factors contributing to variability in total energy expenditure (TEE) among humans. Variation arising from within and between individuals and between study groups will be considered. For within- subject variation, issues relating to experimental and theoretical measurement error will be considered in addition to inherent physiological variation. The literature reporting TEE in various study groups is reviewed, highlighting deficiencies in current comparison methods, and a framework by which TEE can be compared between studies and populations is suggested. For between-subject variation, the effects of differences in body composition, obesity, age and gender upon variation in TEE are examined. Finally, data will be reviewed relating to changes in TEE in response to external manipulation (e.g., activity, overfeeding, stress).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The purpose of this paper is to review current data regarding the factors contributing to variability in total energy expenditure (TEE) among humans. Variation arising from within and between individuals and between study groups will be considered. For within- subject variation, issues relating to experimental and theoretical measurement error will be considered in addition to inherent physiological variation. The literature reporting TEE in various study groups is reviewed, highlighting deficiencies in current comparison methods, and a framework by which TEE can be compared between studies and populations is suggested. For between-subject variation, the effects of differences in body composition, obesity, age and gender upon variation in TEE are examined. Finally, data will be reviewed relating to changes in TEE in response to external manipulation (e.g., activity, overfeeding, stress).
Goran, M I; Kaskoun, M; Johnson, R; Martinez, C; Kelly, B; Hood, V
Energy expenditure and body fat distribution in Mohawk children Journal Article
In: Pediatrics, 95 (1), pp. 89–95, 1995.
@article{pmid7770316,
title = {Energy expenditure and body fat distribution in Mohawk children},
author = {M I Goran and M Kaskoun and R Johnson and C Martinez and B Kelly and V Hood},
year = {1995},
date = {1995-01-01},
journal = {Pediatrics},
volume = {95},
number = {1},
pages = {89--95},
abstract = {Epidemiologic studies suggest that Native Americans, including the Mohawk people, have a high prevalence of obesity, diabetes, and cardiovascular risk. However, current information on alterations in related variables such as energy metabolism and body composition in Native Americans is almost exclusively limited to already obese Pima adults living in the Southwest. The aim of this study was to characterize energy metabolism and body composition in young Mohawk children (17 girls, 11 boys; aged 4 to 7 years) as compared to Caucasian children (36 girls, 34 boys; aged 4 to 7 years). Total energy expenditure was measured by doubly labeled water, postprandial resting energy expenditure by indirect calorimetry, and activity energy expenditure was derived from the difference between total and resting energy expenditure. Fat and fat free mass were estimated from bioelectrical resistance, and body fat distribution was estimated from skinfolds and circumferences. There were no significant effects of ethnic background or sex on body weight, height, or body mass index. Fat free mass was significantly higher in boys and fat mass was significantly higher in girls, with no effect of ethnic background. Chest skinfold thickness, the ratio of trunk skinfolds:extremity skinfolds, and the waist:hip ratio were significantly higher in Mohawk children by 2.5 mm, 0.09 units, and 0.03 units, respectively, independent of sex and fat mass. Total energy expenditure was significantly higher in Mohawk children compared to Caucasian (100 kcal/day in girls, 150 kcal/day in boys), independent of fat free mass and sex, due to a significantly higher physical activity-related energy expenditure. These data suggest that: 1) body fat is more centrally distributed in Mohawk relative to Caucasian children, and this effect is independent of sex and body fat content; 2) Mohawk children have a greater total energy expenditure than Caucasian children, independent of fat free mass, due to greater physical activity-related energy expenditure.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Epidemiologic studies suggest that Native Americans, including the Mohawk people, have a high prevalence of obesity, diabetes, and cardiovascular risk. However, current information on alterations in related variables such as energy metabolism and body composition in Native Americans is almost exclusively limited to already obese Pima adults living in the Southwest. The aim of this study was to characterize energy metabolism and body composition in young Mohawk children (17 girls, 11 boys; aged 4 to 7 years) as compared to Caucasian children (36 girls, 34 boys; aged 4 to 7 years). Total energy expenditure was measured by doubly labeled water, postprandial resting energy expenditure by indirect calorimetry, and activity energy expenditure was derived from the difference between total and resting energy expenditure. Fat and fat free mass were estimated from bioelectrical resistance, and body fat distribution was estimated from skinfolds and circumferences. There were no significant effects of ethnic background or sex on body weight, height, or body mass index. Fat free mass was significantly higher in boys and fat mass was significantly higher in girls, with no effect of ethnic background. Chest skinfold thickness, the ratio of trunk skinfolds:extremity skinfolds, and the waist:hip ratio were significantly higher in Mohawk children by 2.5 mm, 0.09 units, and 0.03 units, respectively, independent of sex and fat mass. Total energy expenditure was significantly higher in Mohawk children compared to Caucasian (100 kcal/day in girls, 150 kcal/day in boys), independent of fat free mass and sex, due to a significantly higher physical activity-related energy expenditure. These data suggest that: 1) body fat is more centrally distributed in Mohawk relative to Caucasian children, and this effect is independent of sex and body fat content; 2) Mohawk children have a greater total energy expenditure than Caucasian children, independent of fat free mass, due to greater physical activity-related energy expenditure.
Carpenter, W H; Poehlman, E T; O'Connell, M; Goran, M I
Influence of body composition and resting metabolic rate on variation in total energy expenditure: a meta-analysis Journal Article
In: Am. J. Clin. Nutr., 61 (1), pp. 4–10, 1995.
@article{pmid7825536,
title = {Influence of body composition and resting metabolic rate on variation in total energy expenditure: a meta-analysis},
author = {W H Carpenter and E T Poehlman and M O'Connell and M I Goran},
year = {1995},
date = {1995-01-01},
journal = {Am. J. Clin. Nutr.},
volume = {61},
number = {1},
pages = {4--10},
abstract = {The influence of body composition, resting metabolic rate (RMR), and sex on variation in total energy expenditure (TEE) was examined by using meta-analysis (13 published studies in a total of 162 adults). TEE (10.9 +/- 3.2 MJ/d) was significantly correlated with body mass (BM; weighted mean converted r = 0.68, P < 0.05) and resting metabolic rate (RMR; weighted mean converted r = 0.66, P < 0.05). The correlation coefficients, regression coefficients, and intercepts for the regression between TEE and RMR and between TEE and BM were highly variable between studies. When TEE was adjusted for RMR, there was no significant correlation with body fat, and females had a significantly lower TEE than males by 1.1 MJ/d (P = 0.005). We conclude that 1) the relationships between TEE and RMR and TEE and BM are highly variable between studies with nonzero intercepts, precluding use of the traditionally used ratios of TEE to RMR or TEE to BM for data comparison; 2) after adjustment of TEE for RMR, TEE is not associated with adiposity, and women have a significantly lower TEE than men; and, 3) there are insufficient published data to develop prediction models for TEE in adults.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The influence of body composition, resting metabolic rate (RMR), and sex on variation in total energy expenditure (TEE) was examined by using meta-analysis (13 published studies in a total of 162 adults). TEE (10.9 +/- 3.2 MJ/d) was significantly correlated with body mass (BM; weighted mean converted r = 0.68, P < 0.05) and resting metabolic rate (RMR; weighted mean converted r = 0.66, P < 0.05). The correlation coefficients, regression coefficients, and intercepts for the regression between TEE and RMR and between TEE and BM were highly variable between studies. When TEE was adjusted for RMR, there was no significant correlation with body fat, and females had a significantly lower TEE than males by 1.1 MJ/d (P = 0.005). We conclude that 1) the relationships between TEE and RMR and TEE and BM are highly variable between studies with nonzero intercepts, precluding use of the traditionally used ratios of TEE to RMR or TEE to BM for data comparison; 2) after adjustment of TEE for RMR, TEE is not associated with adiposity, and women have a significantly lower TEE than men; and, 3) there are insufficient published data to develop prediction models for TEE in adults.
Goran, M I; Kaskoun, M; Shuman, W P
Intra-abdominal adipose tissue in young children Journal Article
In: Int. J. Obes. Relat. Metab. Disord., 19 (4), pp. 279–283, 1995.
@article{pmid7627253,
title = {Intra-abdominal adipose tissue in young children},
author = {M I Goran and M Kaskoun and W P Shuman},
year = {1995},
date = {1995-00-01},
journal = {Int. J. Obes. Relat. Metab. Disord.},
volume = {19},
number = {4},
pages = {279--283},
abstract = {Intra-abdominal adipose tissue (IAAT) is associated with the metabolic complications of obesity. However the time course for the development of IAAT is not clearly defined because it is generally difficult to measure directly. The purposes of this short communication are to present data supporting the existence of IAAT in young children using direct measurement with computed tomography imaging, and to examine the relationship between IAAT and anthropometric indices in 16 healthy children (6.4 +/- 1.2 years; 24.8 +/- 5.4 kg). Total body fat (6.4 +/- 3.5 kg) and fat free mass (18.4 +/- 3.6 kg) were determined by bioelectrical resistance. Fat distribution was estimated from eight individual skinfold measurements, the ratio of three trunk skinfolds to three extremity skinfolds (0.78 +/- 0.20), and the waist:hip ratio (0.90 +/- 0.08). Mean abdominal subcutaneous adipose tissue (SCAT) was 65.3 +/- 44.8 cm2, and mean IAAT was 8.3 +/- 5.8 cm2. The ratio of IAAT to SCAT was 0.15 +/- 0.08, and the ratio of IAAT to total body fat was 1.44 +/- 0.84 cm2/kg. IAAT was significantly correlated with body weight (r = 0.54; P = 0.03), all skinfold measures (range r = 0.60-0.78; P = 0.02 to 0.0003) except at the calf, fat mass (r = 0.69; P = 0.003), and the trunk to extremity skinfold ratio (r = 0.78; P = 0.0003). There was no significant correlation between IAAT and the waist:hip ratio (r = 0.21). These preliminary results establish the existence of IAAT in young children and suggest that individual trunk skinfold measurements and the trunk:extremity skinfold ratio provide a better indication of IAAT compared to the waist:hip ratio. However, as with adults, the relationship between intra-abdominal adipose tissue and anthropometry in children is complex.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Intra-abdominal adipose tissue (IAAT) is associated with the metabolic complications of obesity. However the time course for the development of IAAT is not clearly defined because it is generally difficult to measure directly. The purposes of this short communication are to present data supporting the existence of IAAT in young children using direct measurement with computed tomography imaging, and to examine the relationship between IAAT and anthropometric indices in 16 healthy children (6.4 +/- 1.2 years; 24.8 +/- 5.4 kg). Total body fat (6.4 +/- 3.5 kg) and fat free mass (18.4 +/- 3.6 kg) were determined by bioelectrical resistance. Fat distribution was estimated from eight individual skinfold measurements, the ratio of three trunk skinfolds to three extremity skinfolds (0.78 +/- 0.20), and the waist:hip ratio (0.90 +/- 0.08). Mean abdominal subcutaneous adipose tissue (SCAT) was 65.3 +/- 44.8 cm2, and mean IAAT was 8.3 +/- 5.8 cm2. The ratio of IAAT to SCAT was 0.15 +/- 0.08, and the ratio of IAAT to total body fat was 1.44 +/- 0.84 cm2/kg. IAAT was significantly correlated with body weight (r = 0.54; P = 0.03), all skinfold measures (range r = 0.60-0.78; P = 0.02 to 0.0003) except at the calf, fat mass (r = 0.69; P = 0.003), and the trunk to extremity skinfold ratio (r = 0.78; P = 0.0003). There was no significant correlation between IAAT and the waist:hip ratio (r = 0.21). These preliminary results establish the existence of IAAT in young children and suggest that individual trunk skinfold measurements and the trunk:extremity skinfold ratio provide a better indication of IAAT compared to the waist:hip ratio. However, as with adults, the relationship between intra-abdominal adipose tissue and anthropometry in children is complex.
Treuth, M S; Hunter, G R; Kekes-Szabo, T; Weinsier, R L; Goran, M I; Berland, L
Reduction in intra-abdominal adipose tissue after strength training in older women Journal Article
In: J. Appl. Physiol., 78 (4), pp. 1425–1431, 1995.
@article{pmid7615451,
title = {Reduction in intra-abdominal adipose tissue after strength training in older women},
author = {M S Treuth and G R Hunter and T Kekes-Szabo and R L Weinsier and M I Goran and L Berland},
year = {1995},
date = {1995-00-01},
journal = {J. Appl. Physiol.},
volume = {78},
number = {4},
pages = {1425--1431},
abstract = {The purpose of this study was to examine the effects of a total body strength-training program on changes in total and regional body composition, in particular intra-abdominal adipose tissue (IAAT), in older women. Fourteen healthy older women (mean age 67 +/- 1 yr) exercised 3 times/wk for 16 wk. Strength was assessed by one-repetition maximum tests, with training intensity gradually increased to approximately 67% of one repetition maximum. Body composition was measured by hydrodensitometry and regional body composition was measured by computed tomography. Strength was significantly increased in the upper (51%) and lower body (65%). There was no significant change in body weight (64.4 +/- 2.7 vs. 64.2 +/- 2.7 kg), total body fat (38.7 +/- 1.4 vs. 38.0 +/- 1.6%) or fat-free mass (39.7 +/- 1.0 vs. 40.0 +/- 0.9 kg). However, after ST, there were significant reductions in IAAT (143.9 +/- 13.3 vs. 130.0 +/- 12.4 cm2), the IAAT-to-subcutaneous adipose tissue ratio (0.48 +/- 0.04 vs. 0.44 +/- 0.04), and midthigh subcutaneous adipose tissue (141.7 +/- 11.5 vs. 133.6 +/- 10.8 cm2) and an increase in midthigh muscle (52.9 +/- 2.6 vs. 58.0 +/- 2.0 cm2) (all P < 0.05). In conclusion, significant reductions in IAAT and an increase in strength and muscle area were observed after a strength-training program in healthy older women. These changes may be important in preventing the negative health outcomes associated with the age-related increase in intra-abdominal obesity.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The purpose of this study was to examine the effects of a total body strength-training program on changes in total and regional body composition, in particular intra-abdominal adipose tissue (IAAT), in older women. Fourteen healthy older women (mean age 67 +/- 1 yr) exercised 3 times/wk for 16 wk. Strength was assessed by one-repetition maximum tests, with training intensity gradually increased to approximately 67% of one repetition maximum. Body composition was measured by hydrodensitometry and regional body composition was measured by computed tomography. Strength was significantly increased in the upper (51%) and lower body (65%). There was no significant change in body weight (64.4 +/- 2.7 vs. 64.2 +/- 2.7 kg), total body fat (38.7 +/- 1.4 vs. 38.0 +/- 1.6%) or fat-free mass (39.7 +/- 1.0 vs. 40.0 +/- 0.9 kg). However, after ST, there were significant reductions in IAAT (143.9 +/- 13.3 vs. 130.0 +/- 12.4 cm2), the IAAT-to-subcutaneous adipose tissue ratio (0.48 +/- 0.04 vs. 0.44 +/- 0.04), and midthigh subcutaneous adipose tissue (141.7 +/- 11.5 vs. 133.6 +/- 10.8 cm2) and an increase in midthigh muscle (52.9 +/- 2.6 vs. 58.0 +/- 2.0 cm2) (all P < 0.05). In conclusion, significant reductions in IAAT and an increase in strength and muscle area were observed after a strength-training program in healthy older women. These changes may be important in preventing the negative health outcomes associated with the age-related increase in intra-abdominal obesity.
1994
Goran, M I; Kaskoun, M; Johnson, R
Determinants of resting energy expenditure in young children Journal Article
In: J. Pediatr., 125 (3), pp. 362–367, 1994.
@article{pmid8071742,
title = {Determinants of resting energy expenditure in young children},
author = {M I Goran and M Kaskoun and R Johnson},
year = {1994},
date = {1994-09-01},
journal = {J. Pediatr.},
volume = {125},
number = {3},
pages = {362--367},
abstract = {Resting energy expenditure (REE) in adults is influenced by fat-free mass (FFM) and fat mass (FM), and is significantly higher in men than in women. There are limited data, however, on the physiologic determinants of REE in children. We therefore measured REE in 113 prepubertal children (39 white girls, 41 white boys, 21 Mohawk girls, and 12 Mohawk boys), 3.9 to 7.8 years of age, representing a wide range of body weight (14.7 to 34.0 kg), height (0.97 to 1.30 m), FFM (10.3 to 25.0 kg), and FM (1.7 to 13.7 kg; 9.4% to 40.3%). The REE was measured in duplicate by indirect calorimetry (range, 830 to 1405 kcal/day) while the children were in a postprandial state and viewing a cartoon film. The FM and FFM values were determined by bioelectrical resistance by means of the Kushner equation. In stepwise regression analysis, the combination of FFM (p < 0.001; partial r = 0.77), sex (p = 0.001; partial r = 0.12), and FM (p = 0.01; partial r = 0.16) explained 63% of the variation in REE. The regression coefficients were 31.9 kcal/kg FFM, 53 kcal for boys, 0 for girls, and 13 kcal/kg FM. Mohawk background, age, fat distribution, heart rate, and physical activity were not independently associated with REE. After REE was adjusted for the aforementioned significant factors, there were no significant correlations with parental factors (body composition, physical activity, age, and REE) other than normalized maternal REE (r = 0.19; p = 0.05). We conclude that the effects of FFM, sex, and FM on REE in children are similar to those in adults. The higher REE in young boys suggests that the previously reported higher REE in adult men cannot be explained entirely by differences in sex hormones. Finally, our data do not support the hypothesis that REE in children is negatively influenced by obesity in children or in parents.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Resting energy expenditure (REE) in adults is influenced by fat-free mass (FFM) and fat mass (FM), and is significantly higher in men than in women. There are limited data, however, on the physiologic determinants of REE in children. We therefore measured REE in 113 prepubertal children (39 white girls, 41 white boys, 21 Mohawk girls, and 12 Mohawk boys), 3.9 to 7.8 years of age, representing a wide range of body weight (14.7 to 34.0 kg), height (0.97 to 1.30 m), FFM (10.3 to 25.0 kg), and FM (1.7 to 13.7 kg; 9.4% to 40.3%). The REE was measured in duplicate by indirect calorimetry (range, 830 to 1405 kcal/day) while the children were in a postprandial state and viewing a cartoon film. The FM and FFM values were determined by bioelectrical resistance by means of the Kushner equation. In stepwise regression analysis, the combination of FFM (p < 0.001; partial r = 0.77), sex (p = 0.001; partial r = 0.12), and FM (p = 0.01; partial r = 0.16) explained 63% of the variation in REE. The regression coefficients were 31.9 kcal/kg FFM, 53 kcal for boys, 0 for girls, and 13 kcal/kg FM. Mohawk background, age, fat distribution, heart rate, and physical activity were not independently associated with REE. After REE was adjusted for the aforementioned significant factors, there were no significant correlations with parental factors (body composition, physical activity, age, and REE) other than normalized maternal REE (r = 0.19; p = 0.05). We conclude that the effects of FFM, sex, and FM on REE in children are similar to those in adults. The higher REE in young boys suggests that the previously reported higher REE in adult men cannot be explained entirely by differences in sex hormones. Finally, our data do not support the hypothesis that REE in children is negatively influenced by obesity in children or in parents.
Goran, M I; Poehlman, E T; Danforth, E; Nair, K S
Comparison of body fat estimates derived from underwater weight and total body water Journal Article
In: Int. J. Obes. Relat. Metab. Disord., 18 (9), pp. 622–626, 1994.
@article{pmid7812416,
title = {Comparison of body fat estimates derived from underwater weight and total body water},
author = {M I Goran and E T Poehlman and E Danforth and K S Nair},
year = {1994},
date = {1994-09-01},
journal = {Int. J. Obes. Relat. Metab. Disord.},
volume = {18},
number = {9},
pages = {622--626},
abstract = {The purpose of this study was to compare the techniques of underwater weighing and analysis of total body water for estimating body fat with that derived from a 3-compartment model combining total body density and total body water. Body fat was estimated from: (1) body density using the Siri equation; (2) total body water assuming a hydration factor of 0.73 for fat free mass; and (3) the 3-compartment model combining body density and body water. The criterion method in this study was body fat mass determined from Siri's 3-compartment model. The subjects in this study included 10 obese men (41 +/- 10 years; 115.5 +/- 16.6 kg), 7 elderly men (68 +/- 6 years, 77.1 +/- 7.4 kg), and 18 young men (24 +/- 5 years; 71.0 +/- 9.2 kg). Body density was obtained by underwater weight with simultaneous determination of lung volume by helium dilution. Body water was obtained from zero-time extrapolation of isotope washout over 10-14 days following an oral dose of 2H2O and H2(18)O. Estimates of body fat derived from total body water were significantly higher than that derived from underwater weight in the elderly (1.4 +/- 1.5 kg; P < 0.05) and younger (3.0 +/- 2.8 kg; P < 0.001) men. In the obese subjects, there was no significant difference in body fat estimates between the two techniques (mean difference = 1.3 +/- 5.1 kg). The overestimation of body fat from total body water relative to underwater weight was negatively associated with body fat mass estimated from the 3-compartment model combining measurement of density and water (r = -0.35; P = 0.04). It is concluded that total body water overestimates body fat relative to underwater weight, and that this effect is more pronounced in leaner subjects.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The purpose of this study was to compare the techniques of underwater weighing and analysis of total body water for estimating body fat with that derived from a 3-compartment model combining total body density and total body water. Body fat was estimated from: (1) body density using the Siri equation; (2) total body water assuming a hydration factor of 0.73 for fat free mass; and (3) the 3-compartment model combining body density and body water. The criterion method in this study was body fat mass determined from Siri's 3-compartment model. The subjects in this study included 10 obese men (41 +/- 10 years; 115.5 +/- 16.6 kg), 7 elderly men (68 +/- 6 years, 77.1 +/- 7.4 kg), and 18 young men (24 +/- 5 years; 71.0 +/- 9.2 kg). Body density was obtained by underwater weight with simultaneous determination of lung volume by helium dilution. Body water was obtained from zero-time extrapolation of isotope washout over 10-14 days following an oral dose of 2H2O and H2(18)O. Estimates of body fat derived from total body water were significantly higher than that derived from underwater weight in the elderly (1.4 +/- 1.5 kg; P < 0.05) and younger (3.0 +/- 2.8 kg; P < 0.001) men. In the obese subjects, there was no significant difference in body fat estimates between the two techniques (mean difference = 1.3 +/- 5.1 kg). The overestimation of body fat from total body water relative to underwater weight was negatively associated with body fat mass estimated from the 3-compartment model combining measurement of density and water (r = -0.35; P = 0.04). It is concluded that total body water overestimates body fat relative to underwater weight, and that this effect is more pronounced in leaner subjects.
Kaskoun, M C; Johnson, R K; Goran, M I
Comparison of energy intake by semiquantitative food-frequency questionnaire with total energy expenditure by the doubly labeled water method in young children Journal Article
In: Am. J. Clin. Nutr., 60 (1), pp. 43–47, 1994.
@article{pmid8017336,
title = {Comparison of energy intake by semiquantitative food-frequency questionnaire with total energy expenditure by the doubly labeled water method in young children},
author = {M C Kaskoun and R K Johnson and M I Goran},
year = {1994},
date = {1994-07-01},
journal = {Am. J. Clin. Nutr.},
volume = {60},
number = {1},
pages = {43--47},
abstract = {We assessed the validity of a semiquantitative food-frequency questionnaire to estimate energy intake in young children by comparison with total energy expenditure (TEE). TEE was measured in 45 children (22 males and 23 females; 4.2-6.9 y of age) by the doubly labeled water method and body composition was estimated from bioelectrical resistance (20.2 +/- 4.0 kg body weight, 4.6 +/- 2.1 kg fat mass, and 15.6 +/- 3.1 kg fat-free mass). The sample included 36 white children and 9 Mohawk Native American children. The children's mothers completed one Willett food-frequency questionnaire to reflect the child's usual dietary intake over the last year. Total energy intake by food-frequency questionnaire (9.12 +/- 2.28 MJ/d) was significantly higher than TEE (5.74 +/- 1.13 MJ/d; P < 0.001). Misreporting of intake by food-frequency questionnaire ranged from 9.57 MJ/d overestimation to 1.58 MJ/d underestimation and was not significantly influenced by sex or body composition of the children. We conclude that use of the food-frequency questionnaire significantly overestimates energy intake in children.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We assessed the validity of a semiquantitative food-frequency questionnaire to estimate energy intake in young children by comparison with total energy expenditure (TEE). TEE was measured in 45 children (22 males and 23 females; 4.2-6.9 y of age) by the doubly labeled water method and body composition was estimated from bioelectrical resistance (20.2 +/- 4.0 kg body weight, 4.6 +/- 2.1 kg fat mass, and 15.6 +/- 3.1 kg fat-free mass). The sample included 36 white children and 9 Mohawk Native American children. The children's mothers completed one Willett food-frequency questionnaire to reflect the child's usual dietary intake over the last year. Total energy intake by food-frequency questionnaire (9.12 +/- 2.28 MJ/d) was significantly higher than TEE (5.74 +/- 1.13 MJ/d; P < 0.001). Misreporting of intake by food-frequency questionnaire ranged from 9.57 MJ/d overestimation to 1.58 MJ/d underestimation and was not significantly influenced by sex or body composition of the children. We conclude that use of the food-frequency questionnaire significantly overestimates energy intake in children.
Goran, M I; Calles-Escandon, J; Poehlman, E T; O'Connell, M; Danforth, E
Effects of increased energy intake and/or physical activity on energy expenditure in young healthy men Journal Article
In: J. Appl. Physiol., 77 (1), pp. 366–372, 1994.
@article{pmid7961258,
title = {Effects of increased energy intake and/or physical activity on energy expenditure in young healthy men},
author = {M I Goran and J Calles-Escandon and E T Poehlman and M O'Connell and E Danforth},
year = {1994},
date = {1994-07-01},
journal = {J. Appl. Physiol.},
volume = {77},
number = {1},
pages = {366--372},
abstract = {This study was designed to examine effects of alterations in energy balance on adaptive changes in components of total energy expenditure (TEE). Nineteen young healthy males were studied during a 10-day sedentary energy balance baseline period and then randomly assigned to one of four 10-day treatment groups: 1) no change in energy intake (EI) or physical activity (PA; energy balance at low energy flux), 2) EI increased by 50% with no change in PA (positive energy balance), 3) TEE increased by 50% by increasing PA, matched by a 50% increase in EI (energy balance at high energy flux), and 4) TEE increased by 50% by increasing PA with no change in EI (negative energy balance). TEE was measured with doubly labeled water, resting metabolic rate (RMR) by indirect calorimetry, and thermic response to feeding (TEF) by indirect calorimetry; energy expenditure of physical activity (EEPA) was estimated by subtracting RMR, TEF, and prescribed PA from TEE. TEE was significantly increased by PA (by design) but not EI. There was a significant main effect of intake and a significant intake-by-activity interaction for changes in RMR. In post hoc analysis, RMR was significantly increased during positive energy balance and energy balance at high energy flux relative to change in RMR when energy balance was maintained at low energy flux. A significant increase in RMR was also noted during negative energy balance after adjustment for change in fat-free mass. There was no significant difference in change in RMR among the three treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This study was designed to examine effects of alterations in energy balance on adaptive changes in components of total energy expenditure (TEE). Nineteen young healthy males were studied during a 10-day sedentary energy balance baseline period and then randomly assigned to one of four 10-day treatment groups: 1) no change in energy intake (EI) or physical activity (PA; energy balance at low energy flux), 2) EI increased by 50% with no change in PA (positive energy balance), 3) TEE increased by 50% by increasing PA, matched by a 50% increase in EI (energy balance at high energy flux), and 4) TEE increased by 50% by increasing PA with no change in EI (negative energy balance). TEE was measured with doubly labeled water, resting metabolic rate (RMR) by indirect calorimetry, and thermic response to feeding (TEF) by indirect calorimetry; energy expenditure of physical activity (EEPA) was estimated by subtracting RMR, TEF, and prescribed PA from TEE. TEE was significantly increased by PA (by design) but not EI. There was a significant main effect of intake and a significant intake-by-activity interaction for changes in RMR. In post hoc analysis, RMR was significantly increased during positive energy balance and energy balance at high energy flux relative to change in RMR when energy balance was maintained at low energy flux. A significant increase in RMR was also noted during negative energy balance after adjustment for change in fat-free mass. There was no significant difference in change in RMR among the three treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Johnson, R K; Goran, M I; Poehlman, E T
Correlates of over- and underreporting of energy intake in healthy older men and women Journal Article
In: Am. J. Clin. Nutr., 59 (6), pp. 1286–1290, 1994.
@article{pmid8198052,
title = {Correlates of over- and underreporting of energy intake in healthy older men and women},
author = {R K Johnson and M I Goran and E T Poehlman},
year = {1994},
date = {1994-06-01},
journal = {Am. J. Clin. Nutr.},
volume = {59},
number = {6},
pages = {1286--1290},
abstract = {The aim of this study was to determine whether variations in physiological characteristics were predictive of over- or underreporting of energy intake in older men and women. Total energy expenditure was predicted in 81 older men (66 +/- 6 y) and 56 older women (66 +/- 6 y) from a previously developed equation that uses the doubly labeled water method. The degree of over- or underreporting of energy intake was derived by subtracting predicted total daily energy expenditure from self-reported energy intake obtained from a 3-d diet record. Older women underreported energy intake (-2206 kJ/d +/- 1841) to a greater degree than did older men (-1301 kJ/d +/- 1908) (P < or = 0.01). In men, none of the physiological variables were significantly correlated with over- or underreporting of energy intake. Among the women, percent body fat was negatively correlated with underreporting of energy intake (r = -0.42},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The aim of this study was to determine whether variations in physiological characteristics were predictive of over- or underreporting of energy intake in older men and women. Total energy expenditure was predicted in 81 older men (66 +/- 6 y) and 56 older women (66 +/- 6 y) from a previously developed equation that uses the doubly labeled water method. The degree of over- or underreporting of energy intake was derived by subtracting predicted total daily energy expenditure from self-reported energy intake obtained from a 3-d diet record. Older women underreported energy intake (-2206 kJ/d +/- 1841) to a greater degree than did older men (-1301 kJ/d +/- 1908) (P < or = 0.01). In men, none of the physiological variables were significantly correlated with over- or underreporting of energy intake. Among the women, percent body fat was negatively correlated with underreporting of energy intake (r = -0.42
Poehlman, E T; Gardner, A W; Arciero, P J; Goran, M I; Calles-Escandon, J
Effects of endurance training on total fat oxidation in elderly persons Journal Article
In: J. Appl. Physiol., 76 (6), pp. 2281–2287, 1994.
@article{pmid7928848,
title = {Effects of endurance training on total fat oxidation in elderly persons},
author = {E T Poehlman and A W Gardner and P J Arciero and M I Goran and J Calles-Escandon},
year = {1994},
date = {1994-06-01},
journal = {J. Appl. Physiol.},
volume = {76},
number = {6},
pages = {2281--2287},
abstract = {We examined the influence of 8 wk of endurance training on basal levels of fat oxidation and its association with changes in norepinephrine (NE) kinetics, resting metabolic rate (RMR), and body composition in 18 healthy elderly persons (66.1 +/- 1.4 yr; 10 men, 8 women). Fatty acid appearance rate and total body fat oxidation were determined from [14C]palmitate infusion and indirect calorimetry, NE kinetics were determined from infusions of [3H]NE, RMR was determined from the ventilated hood technique, and body composition was determined from underwater weighing. Endurance training increased peak oxygen consumption by 11% (1.9 +/- 0.1 to 2.1 +/- 0.1 l/min; P < 0.01) and increased RMR by 7% (1.20 +/- 0.02 to 1.28 +/- 0.02 kcal/min; P < 0.01). Endurance training increased NE appearance rate by 35% (0.51 +/- 0.04 to 0.69 +/- 0.04 micrograms/min; P < 0.01), whereas no change in NE clearance was noted. Endurance training increased fat oxidation by 22% (201.0 +/- 11.2 vs. 244.0 +/- 15.2 mumol/min; P < 0.01) but did not alter fatty acid appearance rate. Approximately two-thirds of the variation (r2 = 0.65) for the increase in fat oxidation was explained by increased NE appearance rate (r2 = 0.51; P < 0.01) and changes in fat-free weight (r2 = 0.14; P < 0.01). We conclude that 1) endurance training shifts in vivo basal substrate utilization toward greater fat oxidation in elderly individuals and 2) enhanced fat oxidation is associated with increased activity of the sympathetic nervous system and alterations in fat-free mass.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We examined the influence of 8 wk of endurance training on basal levels of fat oxidation and its association with changes in norepinephrine (NE) kinetics, resting metabolic rate (RMR), and body composition in 18 healthy elderly persons (66.1 +/- 1.4 yr; 10 men, 8 women). Fatty acid appearance rate and total body fat oxidation were determined from [14C]palmitate infusion and indirect calorimetry, NE kinetics were determined from infusions of [3H]NE, RMR was determined from the ventilated hood technique, and body composition was determined from underwater weighing. Endurance training increased peak oxygen consumption by 11% (1.9 +/- 0.1 to 2.1 +/- 0.1 l/min; P < 0.01) and increased RMR by 7% (1.20 +/- 0.02 to 1.28 +/- 0.02 kcal/min; P < 0.01). Endurance training increased NE appearance rate by 35% (0.51 +/- 0.04 to 0.69 +/- 0.04 micrograms/min; P < 0.01), whereas no change in NE clearance was noted. Endurance training increased fat oxidation by 22% (201.0 +/- 11.2 vs. 244.0 +/- 15.2 mumol/min; P < 0.01) but did not alter fatty acid appearance rate. Approximately two-thirds of the variation (r2 = 0.65) for the increase in fat oxidation was explained by increased NE appearance rate (r2 = 0.51; P < 0.01) and changes in fat-free weight (r2 = 0.14; P < 0.01). We conclude that 1) endurance training shifts in vivo basal substrate utilization toward greater fat oxidation in elderly individuals and 2) enhanced fat oxidation is associated with increased activity of the sympathetic nervous system and alterations in fat-free mass.
Goran, M I; Poehlman, E T; Danforth, E
Experimental reliability of the doubly labeled water technique Journal Article
In: Am. J. Physiol., 266 (3 Pt 1), pp. E510–515, 1994.
@article{pmid8166273,
title = {Experimental reliability of the doubly labeled water technique},
author = {M I Goran and E T Poehlman and E Danforth},
year = {1994},
date = {1994-03-01},
journal = {Am. J. Physiol.},
volume = {266},
number = {3 Pt 1},
pages = {E510--515},
abstract = {The experimental reliability of measuring CO2 production rates (rCO2) with the doubly labeled water (DLW) technique was assessed in five young healthy men (23 (DLW) technique was assessed in five young healthy men (23 +/- 4 yr; 66.1 +/- 4.6 kg). To minimize the confounding effects of fluctuations in physical activity and eating patterns on variation in energy expenditure, the subjects lived under sedentary living conditions by confinement to their own room at a Clinical Research Center and were maintained on a fixed and known level of energy intake. rCO2 was determined in duplicate over two identical 9-day study periods after separate loading doses of deuterium and oxygen-18. Turnover rates were determined from multipoint sampling to reduce error from analytical uncertainty. Dilution spaces were determined by both the intercept and plateau methods. The average experimental variation for rCO2 estimates was approximately +/- 8.5% and was not significantly different among three published calculation models that differ in their assumptions regarding the relationship between the dilution spaces of deuterium and oxygen-18. The experimental reliability of +/- 8.5% exceeds theoretical values generated from calculations based on propagation of error from analytical uncertainty. Between subjects, the experimental variation ranged from 1 to 21%, and the half-width of the 95% confidence interval for the precision of rCO2 estimates was high (+/- 12 mol/day) relative to the mean reported value of approximately 16 mol/day.(ABSTRACT TRUNCATED AT 250 WORDS)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The experimental reliability of measuring CO2 production rates (rCO2) with the doubly labeled water (DLW) technique was assessed in five young healthy men (23 (DLW) technique was assessed in five young healthy men (23 +/- 4 yr; 66.1 +/- 4.6 kg). To minimize the confounding effects of fluctuations in physical activity and eating patterns on variation in energy expenditure, the subjects lived under sedentary living conditions by confinement to their own room at a Clinical Research Center and were maintained on a fixed and known level of energy intake. rCO2 was determined in duplicate over two identical 9-day study periods after separate loading doses of deuterium and oxygen-18. Turnover rates were determined from multipoint sampling to reduce error from analytical uncertainty. Dilution spaces were determined by both the intercept and plateau methods. The average experimental variation for rCO2 estimates was approximately +/- 8.5% and was not significantly different among three published calculation models that differ in their assumptions regarding the relationship between the dilution spaces of deuterium and oxygen-18. The experimental reliability of +/- 8.5% exceeds theoretical values generated from calculations based on propagation of error from analytical uncertainty. Between subjects, the experimental variation ranged from 1 to 21%, and the half-width of the 95% confidence interval for the precision of rCO2 estimates was high (+/- 12 mol/day) relative to the mean reported value of approximately 16 mol/day.(ABSTRACT TRUNCATED AT 250 WORDS)
Poehlman, E T; Arciero, P J; Goran, M I
Endurance exercise in aging humans: effects on energy metabolism Journal Article
In: Exerc Sport Sci Rev, 22 , pp. 251–284, 1994.
@article{pmid7925546,
title = {Endurance exercise in aging humans: effects on energy metabolism},
author = {E T Poehlman and P J Arciero and M I Goran},
year = {1994},
date = {1994-01-01},
journal = {Exerc Sport Sci Rev},
volume = {22},
pages = {251--284},
abstract = {In summary, data suggest that the decline in RMR with advancing age is primarily related to the decline in fat-free mass. However, in addition to the erosion of fat-free mass, other factors such as Na-K pump activity, fat mass, maximal aerobic power, and menopausal status are important determinants influencing the decline in RMR in older individuals. Second, we provide revised prediction equations for RMR that are both gender- and sex-specific and use easily measured variables to facilitate their use in clinical and field settings. Third, preliminary studies suggest that older individuals may have a reduced energy expenditure following meal ingestion, although this is not a universal finding among investigators. Furthermore, several studies suggest that physically active older men exhibit higher thermic responses to a meal than sedentary older men. Data on total energy expenditure in free-living elderly persons are sparse. However, the available data suggest that there is large variation in total energy expenditure in the elderly population, caused primarily by differences in physical activity. The heterogeneity in physical activity makes estimation of individual energy requirements difficult. However, preliminary studies have suggested that measurement of VO2max and other activity indices may be useful markers for estimating energy requirements on an individual basis. Furthermore, attempting to "normalize" total energy expenditure in the elderly by prescribing physical activity is not as straightforward as it seems, due to exercise-induced compensatory reductions in physical activity during the remainder of the day. Levels of insulin-like growth factor-1 decline with advancing age. Preliminary evidence from cross-sectional and exercise intervention studies suggest that the lower serum levels of IGF-1 in older individuals may be partially due to diminished physical activity. Aging is associated with an increase in fasting levels of norepinephrine, primarily influenced by an elevated rate of norepinephrine into circulation; however, the clinical significance of the elevated sympathetic tone is unclear. Endurance training in older individuals has been found to increase basal levels of norepinephrine appearance into circulation, and this has been associated with an increased RMR and enhanced fat oxidation. Optimal exercise interventions need to be identified for the elderly, which maximally increase daily energy expenditure and offset metabolic deterioration with advancing age.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In summary, data suggest that the decline in RMR with advancing age is primarily related to the decline in fat-free mass. However, in addition to the erosion of fat-free mass, other factors such as Na-K pump activity, fat mass, maximal aerobic power, and menopausal status are important determinants influencing the decline in RMR in older individuals. Second, we provide revised prediction equations for RMR that are both gender- and sex-specific and use easily measured variables to facilitate their use in clinical and field settings. Third, preliminary studies suggest that older individuals may have a reduced energy expenditure following meal ingestion, although this is not a universal finding among investigators. Furthermore, several studies suggest that physically active older men exhibit higher thermic responses to a meal than sedentary older men. Data on total energy expenditure in free-living elderly persons are sparse. However, the available data suggest that there is large variation in total energy expenditure in the elderly population, caused primarily by differences in physical activity. The heterogeneity in physical activity makes estimation of individual energy requirements difficult. However, preliminary studies have suggested that measurement of VO2max and other activity indices may be useful markers for estimating energy requirements on an individual basis. Furthermore, attempting to "normalize" total energy expenditure in the elderly by prescribing physical activity is not as straightforward as it seems, due to exercise-induced compensatory reductions in physical activity during the remainder of the day. Levels of insulin-like growth factor-1 decline with advancing age. Preliminary evidence from cross-sectional and exercise intervention studies suggest that the lower serum levels of IGF-1 in older individuals may be partially due to diminished physical activity. Aging is associated with an increase in fasting levels of norepinephrine, primarily influenced by an elevated rate of norepinephrine into circulation; however, the clinical significance of the elevated sympathetic tone is unclear. Endurance training in older individuals has been found to increase basal levels of norepinephrine appearance into circulation, and this has been associated with an increased RMR and enhanced fat oxidation. Optimal exercise interventions need to be identified for the elderly, which maximally increase daily energy expenditure and offset metabolic deterioration with advancing age.
1993
Resting metabolic rate is lower in women than in men Journal Article
In: J. Appl. Physiol., 75 (6), pp. 2514–2520, 1993.
@article{pmid8125870,
title = {Resting metabolic rate is lower in women than in men},
year = {1993},
date = {1993-12-01},
journal = {J. Appl. Physiol.},
volume = {75},
number = {6},
pages = {2514--2520},
abstract = {This study examined gender differences in resting metabolic rate (RMR) across a broad age spectrum after controlling for differences in body composition and aerobic fitness. Three hundred twenty-eight healthy men (17-80 yr) and 194 women (18-81 yr) volunteers were characterized for RMR, body composition, physical activity, peak oxygen consumption (peak VO2), anthropometrics, and energy intake. Measured RMR was 23% higher (P < 0.01) in men (1,740 +/- 194 kcal/day) than in women (1,348 +/- 125 kcal/day). Multiple regression analysis showed that 84% of individual variation in RMR was explained by fat-free mass, fat mass, peak VO2, and gender. After controlling for differences in fat-free mass, fat mass, and peak VO2, a lower RMR (3%; P < 0.01) persisted in women (1,563 +/- 153 kcal/day) compared with men (1,613 +/- 127 kcal/day). Adjusted RMR in premenopausal (P < 0.01) and postmenopausal (P < 0.05) women was lower than in men of a similar age. Our results support a lower RMR in women than in men that is independent of differences in body composition and aerobic fitness.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This study examined gender differences in resting metabolic rate (RMR) across a broad age spectrum after controlling for differences in body composition and aerobic fitness. Three hundred twenty-eight healthy men (17-80 yr) and 194 women (18-81 yr) volunteers were characterized for RMR, body composition, physical activity, peak oxygen consumption (peak VO2), anthropometrics, and energy intake. Measured RMR was 23% higher (P < 0.01) in men (1,740 +/- 194 kcal/day) than in women (1,348 +/- 125 kcal/day). Multiple regression analysis showed that 84% of individual variation in RMR was explained by fat-free mass, fat mass, peak VO2, and gender. After controlling for differences in fat-free mass, fat mass, and peak VO2, a lower RMR (3%; P < 0.01) persisted in women (1,563 +/- 153 kcal/day) compared with men (1,613 +/- 127 kcal/day). Adjusted RMR in premenopausal (P < 0.01) and postmenopausal (P < 0.05) women was lower than in men of a similar age. Our results support a lower RMR in women than in men that is independent of differences in body composition and aerobic fitness.
Toth, M J; Goran, M I; Ades, P A; Howard, D B; Poehlman, E T
Examination of data normalization procedures for expressing peak VO2 data Journal Article
In: J. Appl. Physiol., 75 (5), pp. 2288–2292, 1993.
@article{pmid7695668,
title = {Examination of data normalization procedures for expressing peak VO2 data},
author = {M J Toth and M I Goran and P A Ades and D B Howard and E T Poehlman},
year = {1993},
date = {1993-11-01},
journal = {J. Appl. Physiol.},
volume = {75},
number = {5},
pages = {2288--2292},
abstract = {Peak O2 uptake (VO2) has traditionally been compared among individuals differing in body composition by dividing measured values (1/min) by fat-free mass (FFM) (i.e., ratio method). However, the ability of the ratio method to mathematically remove the confounding influence of FFM from peak VO2 has recently been questioned. Therefore, we compared the effectiveness of the ratio method vs. regression modeling to normalize peak VO2 in a large cohort of males and females for differences in FFM. Regression modeling adjusts peak VO2 according to the relationship derived from the regression of peak VO2 on FFM. Results showed that peak VO2 was 60% higher in males (3.53 +/- 1.01/min) than in females (2.22 +/- 0.6 l/min; P < 0.01). With the ratio method (i.e., peak VO2/FFM), peak VO2 was 15% higher in males (54.6 +/- 12 ml.kg FFM-1.min-1) than in females (47.4 +/- 11 ml.kg FFM-1.min-1; P < 0.01). In contrast, when a regression-based approach was employed to normalize values, no significant difference in adjusted peak VO2 was observed between males and females (3.04 +/- 0.9 vs. 3.01 +/- 1.0 l/min). In conclusion, dividing peak VO2 by FFM can produce spurious results, because this approach does not take into account the nonzero intercept. Therefore, a regression-based approach should be used to normalize peak VO2.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Peak O2 uptake (VO2) has traditionally been compared among individuals differing in body composition by dividing measured values (1/min) by fat-free mass (FFM) (i.e., ratio method). However, the ability of the ratio method to mathematically remove the confounding influence of FFM from peak VO2 has recently been questioned. Therefore, we compared the effectiveness of the ratio method vs. regression modeling to normalize peak VO2 in a large cohort of males and females for differences in FFM. Regression modeling adjusts peak VO2 according to the relationship derived from the regression of peak VO2 on FFM. Results showed that peak VO2 was 60% higher in males (3.53 +/- 1.01/min) than in females (2.22 +/- 0.6 l/min; P < 0.01). With the ratio method (i.e., peak VO2/FFM), peak VO2 was 15% higher in males (54.6 +/- 12 ml.kg FFM-1.min-1) than in females (47.4 +/- 11 ml.kg FFM-1.min-1; P < 0.01). In contrast, when a regression-based approach was employed to normalize values, no significant difference in adjusted peak VO2 was observed between males and females (3.04 +/- 0.9 vs. 3.01 +/- 1.0 l/min). In conclusion, dividing peak VO2 by FFM can produce spurious results, because this approach does not take into account the nonzero intercept. Therefore, a regression-based approach should be used to normalize peak VO2.
Speakman, J R; Nair, K S; Goran, M I
Revised equations for calculating CO2 production from doubly labeled water in humans Journal Article
In: Am. J. Physiol., 264 (6 Pt 1), pp. E912–917, 1993.
@article{pmid8333517,
title = {Revised equations for calculating CO2 production from doubly labeled water in humans},
author = {J R Speakman and K S Nair and M I Goran},
year = {1993},
date = {1993-06-01},
journal = {Am. J. Physiol.},
volume = {264},
number = {6 Pt 1},
pages = {E912--917},
abstract = {The Schoeller model for calculating rate of CO2 production (rCO2) from doubly labeled water (DLW) relies on the assumption that deuterium and oxygen-18 overestimate body water by 4 and 1%, respectively. However, the deuterium-to-oxygen-18 dilution space ratio (DSR) varies considerably, and it is unknown whether this is due to analytical or biological sources. From 161 published values in adult humans, we derived a mean DSR of 1.0427 +/- 0.0218. Propagation of error suggests that analytical uncertainty accounts for 20-50% of the observed variation in the DSR, whereas reliability testing in vivo and in vitro demonstrate that 70-100% of observed interindividual variation in the DSR can be attributed to analytical uncertainty. The discrepancy between propagated error and experimental reliability suggest that it is unwise to rely on propagation of error when evaluating sources of error in DLW. The new constant of 1.0427 was used to revise existing equations for calculating rCO2 from DLW. Compared with the existing equation, the revised equation improved the accuracy (-0.38 vs. +10.3%) and the precision (9.3 vs 10.7%) of rCO2 calculations in previously published validation studies. We conclude that 1) variation in the oxygen-18-to-deuterium DSR is primarily influenced by analytical noise and warrants use of a fixed ratio, 2) existing equations should be revised because the original DSR may have been underestimated, and 3) the modified equations improve the accuracy and precision of rCO2 calculated from DLW.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The Schoeller model for calculating rate of CO2 production (rCO2) from doubly labeled water (DLW) relies on the assumption that deuterium and oxygen-18 overestimate body water by 4 and 1%, respectively. However, the deuterium-to-oxygen-18 dilution space ratio (DSR) varies considerably, and it is unknown whether this is due to analytical or biological sources. From 161 published values in adult humans, we derived a mean DSR of 1.0427 +/- 0.0218. Propagation of error suggests that analytical uncertainty accounts for 20-50% of the observed variation in the DSR, whereas reliability testing in vivo and in vitro demonstrate that 70-100% of observed interindividual variation in the DSR can be attributed to analytical uncertainty. The discrepancy between propagated error and experimental reliability suggest that it is unwise to rely on propagation of error when evaluating sources of error in DLW. The new constant of 1.0427 was used to revise existing equations for calculating rCO2 from DLW. Compared with the existing equation, the revised equation improved the accuracy (-0.38 vs. +10.3%) and the precision (9.3 vs 10.7%) of rCO2 calculations in previously published validation studies. We conclude that 1) variation in the oxygen-18-to-deuterium DSR is primarily influenced by analytical noise and warrants use of a fixed ratio, 2) existing equations should be revised because the original DSR may have been underestimated, and 3) the modified equations improve the accuracy and precision of rCO2 calculated from DLW.
Goran, M I; Carpenter, W H; Poehlman, E T
Total energy expenditure in 4- to 6-yr-old children Journal Article
In: Am. J. Physiol., 264 (5 Pt 1), pp. E706–711, 1993.
@article{pmid8388637,
title = {Total energy expenditure in 4- to 6-yr-old children},
author = {M I Goran and W H Carpenter and E T Poehlman},
year = {1993},
date = {1993-05-01},
journal = {Am. J. Physiol.},
volume = {264},
number = {5 Pt 1},
pages = {E706--711},
abstract = {There is a sparsity of data on energy expenditure in young children. We therefore examined the components of daily energy expenditure in a group of 30 children (16 boys, 14 girls; age 4-6 yr) characterized for body weight, height, heart rate, and body composition from bioelectrical resistance. Total energy expenditure (TEE) was measured over 14 days under free living conditions by doubly labeled water, resting energy expenditure (REE) from indirect calorimetry, and activity energy expenditure was estimated from the difference between TEE and REE. Mean TEE was 1,379 +/- 290 kcal/day, which was 475 +/- 202 kcal/day lower than energy intake recommendations for this age group. Activity-related energy expenditure was estimated to be 267 +/- 203 kcal/day. TEE was most significantly related to fat-free mass (FFM; r = 0.86; P < 0.001), body weight (r = 0.83; P < 0.001), and REE (r = 0.80; P < 0.001). When TEE was adjusted for FFM, a significant correlation with heart rate was observed (partial r = 0.54; P = 0.002). Collectively, 86% of interindividual variation in TEE was accounted for by FFM, heart rate, and REE. We conclude that, in young 4- to 6-yr-old children, 1) TEE is approximately 25% lower than current recommendations for energy intake and 2) combined measurement of FFM, heart rate, and REE explain 86% of interindividual variation in TEE, thus providing a possible alternative method to estimate TEE in young children.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
There is a sparsity of data on energy expenditure in young children. We therefore examined the components of daily energy expenditure in a group of 30 children (16 boys, 14 girls; age 4-6 yr) characterized for body weight, height, heart rate, and body composition from bioelectrical resistance. Total energy expenditure (TEE) was measured over 14 days under free living conditions by doubly labeled water, resting energy expenditure (REE) from indirect calorimetry, and activity energy expenditure was estimated from the difference between TEE and REE. Mean TEE was 1,379 +/- 290 kcal/day, which was 475 +/- 202 kcal/day lower than energy intake recommendations for this age group. Activity-related energy expenditure was estimated to be 267 +/- 203 kcal/day. TEE was most significantly related to fat-free mass (FFM; r = 0.86; P < 0.001), body weight (r = 0.83; P < 0.001), and REE (r = 0.80; P < 0.001). When TEE was adjusted for FFM, a significant correlation with heart rate was observed (partial r = 0.54; P = 0.002). Collectively, 86% of interindividual variation in TEE was accounted for by FFM, heart rate, and REE. We conclude that, in young 4- to 6-yr-old children, 1) TEE is approximately 25% lower than current recommendations for energy intake and 2) combined measurement of FFM, heart rate, and REE explain 86% of interindividual variation in TEE, thus providing a possible alternative method to estimate TEE in young children.
Poehlman, E T; Goran, M I; Gardner, A W; Ades, P A; Arciero, P J; Katzman-Rooks, S M; Montgomery, S M; Toth, M J; Sutherland, P T
Determinants of decline in resting metabolic rate in aging females Journal Article
In: Am. J. Physiol., 264 (3 Pt 1), pp. E450–455, 1993.
@article{pmid8460693,
title = {Determinants of decline in resting metabolic rate in aging females},
author = {E T Poehlman and M I Goran and A W Gardner and P A Ades and P J Arciero and S M Katzman-Rooks and S M Montgomery and M J Toth and P T Sutherland},
year = {1993},
date = {1993-03-01},
journal = {Am. J. Physiol.},
volume = {264},
number = {3 Pt 1},
pages = {E450--455},
abstract = {We considered the association of several metabolic and lifestyle variables as modulators of the decline in resting metabolic rate (RMR) and fat-free weight (FFW) in 183 healthy females (18-81 yr). RMR showed a curvilinear decline with age, which was significant in women aged 51-81 yr but not in women aged 18-50 yr. FFW showed a curvilinear decline with age, which was significant (P < 0.01) in women 48-81 yr but not in women 18-47 yr. The decline in RMR was primarily associated with the loss of FFW (r2 = 72%), whereas the decline in FFW was explained primarily by differences in maximal O2 consumption (VO2max), age, leisure time physical activity, and dietary protein intake (total r2 = 46%). We conclude that RMR and FFW showed a curvilinear decline with age which was accelerated beyond the middle-age years. Second, the age-related decline in RMR was primarily associated with the loss of FFW. Third, the loss of FFW was partially related to a decrement in VO2max and nutritional factors. Therapeutic interventions designed to increase VO2max by elevating physical activity may preserve fat-free weight and thus offset the decline of RMR in aging women.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We considered the association of several metabolic and lifestyle variables as modulators of the decline in resting metabolic rate (RMR) and fat-free weight (FFW) in 183 healthy females (18-81 yr). RMR showed a curvilinear decline with age, which was significant in women aged 51-81 yr but not in women aged 18-50 yr. FFW showed a curvilinear decline with age, which was significant (P < 0.01) in women 48-81 yr but not in women 18-47 yr. The decline in RMR was primarily associated with the loss of FFW (r2 = 72%), whereas the decline in FFW was explained primarily by differences in maximal O2 consumption (VO2max), age, leisure time physical activity, and dietary protein intake (total r2 = 46%). We conclude that RMR and FFW showed a curvilinear decline with age which was accelerated beyond the middle-age years. Second, the age-related decline in RMR was primarily associated with the loss of FFW. Third, the loss of FFW was partially related to a decrement in VO2max and nutritional factors. Therapeutic interventions designed to increase VO2max by elevating physical activity may preserve fat-free weight and thus offset the decline of RMR in aging women.
Goran, M I; Poehlman, E T; Danforth, E; Nair, K S
Comparison of body composition methods in obese individuals Journal Article
In: Basic Life Sci., 60 , pp. 85–86, 1993.
BibTeX | Tags:
@article{pmid8110171,
title = {Comparison of body composition methods in obese individuals},
author = {M I Goran and E T Poehlman and E Danforth and K S Nair},
year = {1993},
date = {1993-01-01},
journal = {Basic Life Sci.},
volume = {60},
pages = {85--86},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Goran, M I; Poehlman, E T; Nair, K S; Danforth, E
Deuterium exchange in humans: effect of gender, body composition and age Journal Article
In: Basic Life Sci., 60 , pp. 79–81, 1993.
BibTeX | Tags:
@article{pmid8110169,
title = {Deuterium exchange in humans: effect of gender, body composition and age},
author = {M I Goran and E T Poehlman and K S Nair and E Danforth},
year = {1993},
date = {1993-01-01},
journal = {Basic Life Sci.},
volume = {60},
pages = {79--81},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Goran, M I; Kaskoun, M C; Carpenter, W H; Poehlman, E T; Ravussin, E; Fontvieille, A M
Estimating body composition of young children by using bioelectrical resistance Journal Article
In: J. Appl. Physiol., 75 (4), pp. 1776–1780, 1993.
@article{pmid8282631,
title = {Estimating body composition of young children by using bioelectrical resistance},
author = {M I Goran and M C Kaskoun and W H Carpenter and E T Poehlman and E Ravussin and A M Fontvieille},
year = {1993},
date = {1993-00-01},
journal = {J. Appl. Physiol.},
volume = {75},
number = {4},
pages = {1776--1780},
abstract = {It is currently unclear whether age-specific equations should be used for assessing body composition from bioelectrical resistance. Kushner et al. (Am. J. Clin. Nutr. 56: 835-839, 1992) showed that the relationship between height2/resistance and total body water (TBW) is robust across a wide age range, although uncertainty remained over the relationship in preschool children. We therefore cross-validated the Kushner equation for predicting total body water in 4- to 6-yr-old children in two independent laboratories. TBW was measured from H2 18O dilution, and bioelectrical resistance and reactance were measured using an RJL 101A analyzer in 31 children (15 females, 16 males; 5 +/- 0.8 yr) studied in Burlington, Vermont, and 30 children (14 females, 16 males; 5 +/- 0.2 yr) studied in Phoenix, Arizona. There was no significant difference between TBW predicted from the Kushner equation and that measured in children in Burlington (11.76 +/- 2.00 vs. 11.91 +/- 2.46 kg; r = 0.94) or in Phoenix (11.53 +/- 1.64 vs. 11.66 +/- 1.90 kg; r = 0.94). The Kushner equation for TBW can be transformed into an equation for fat-free mass (FFM) by using published age- and gender-specific constants for the hydration of FFM: hydration of FFM = 76.9 - 0.25 age (yr) - 1.9 gender where female equals 0 and male equals 1. The intraclass reliability for estimates of fat mass and FFM with the use of bioelectrical resistance in an independent group of 26 children (5.0 +/- 0.8 yr, 20.2 +/- 3.0 kg) was > 0.99 for duplicate observations performed 2 wk apart.(ABSTRACT TRUNCATED AT 250 WORDS)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
It is currently unclear whether age-specific equations should be used for assessing body composition from bioelectrical resistance. Kushner et al. (Am. J. Clin. Nutr. 56: 835-839, 1992) showed that the relationship between height2/resistance and total body water (TBW) is robust across a wide age range, although uncertainty remained over the relationship in preschool children. We therefore cross-validated the Kushner equation for predicting total body water in 4- to 6-yr-old children in two independent laboratories. TBW was measured from H2 18O dilution, and bioelectrical resistance and reactance were measured using an RJL 101A analyzer in 31 children (15 females, 16 males; 5 +/- 0.8 yr) studied in Burlington, Vermont, and 30 children (14 females, 16 males; 5 +/- 0.2 yr) studied in Phoenix, Arizona. There was no significant difference between TBW predicted from the Kushner equation and that measured in children in Burlington (11.76 +/- 2.00 vs. 11.91 +/- 2.46 kg; r = 0.94) or in Phoenix (11.53 +/- 1.64 vs. 11.66 +/- 1.90 kg; r = 0.94). The Kushner equation for TBW can be transformed into an equation for fat-free mass (FFM) by using published age- and gender-specific constants for the hydration of FFM: hydration of FFM = 76.9 - 0.25 age (yr) - 1.9 gender where female equals 0 and male equals 1. The intraclass reliability for estimates of fat mass and FFM with the use of bioelectrical resistance in an independent group of 26 children (5.0 +/- 0.8 yr, 20.2 +/- 3.0 kg) was > 0.99 for duplicate observations performed 2 wk apart.(ABSTRACT TRUNCATED AT 250 WORDS)
A practical equation to predict resting metabolic rate in older men Journal Article
In: Metab. Clin. Exp., 42 (8), pp. 950–957, 1993.
@article{pmid8345818,
title = {A practical equation to predict resting metabolic rate in older men},
year = {1993},
date = {1993-00-01},
journal = {Metab. Clin. Exp.},
volume = {42},
number = {8},
pages = {950--957},
abstract = {The accuracy of previous equations for predicting resting metabolic rate (RMR) in healthy older men is questionable because they are based on limited sample sizes and the absence of cross-validation procedures. The purposes of this study were to (1) examine biological predictors of RMR in healthy older men; (2) develop a practical equation to predict RMR from easily measured variables and examine its accuracy using cross-validation procedures; and (3) test the validity of existing equations in the literature to predict RMR in older men by comparison with measured RMR values. RMR, body composition, anthropometric measurements, leisure time activity (LTA), maximal aerobic power (VO2max), energy intake, and plasma thyroid hormone levels were determined in 89 healthy older men aged 50 to 78 years. Stepwise regression analysis showed that RMR was best predicted by fat-free weight ([FFW] R2 = 85%), free 3,5,3'-triiodothyronine (T3) level (R2 = 1%), and VO2max (R2 = 1%); these variables predicted RMR with a residual error of +/- 30 kcal/d. A practical equation was developed in a randomly selected subsample (N = 61) using easily measured variables as potential predictors, and was successfully cross-validated in a random subsample of older men (N = 28). The pooled equation to predict RMR is as follows: RMR (in kilocalories per day) = 9.7 (weight in kilograms) - 6.1 (chest skinfold thickness in millimeters) - 1.8 (age in years) + 0.1 (leisure time activity [LTA] in kilocalories per day) + 1,060. These variables accounted for 76% (R2) of the variation, and predicted RMR with a residual error of +/- 42 kcal/d.(ABSTRACT TRUNCATED AT 250 WORDS)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The accuracy of previous equations for predicting resting metabolic rate (RMR) in healthy older men is questionable because they are based on limited sample sizes and the absence of cross-validation procedures. The purposes of this study were to (1) examine biological predictors of RMR in healthy older men; (2) develop a practical equation to predict RMR from easily measured variables and examine its accuracy using cross-validation procedures; and (3) test the validity of existing equations in the literature to predict RMR in older men by comparison with measured RMR values. RMR, body composition, anthropometric measurements, leisure time activity (LTA), maximal aerobic power (VO2max), energy intake, and plasma thyroid hormone levels were determined in 89 healthy older men aged 50 to 78 years. Stepwise regression analysis showed that RMR was best predicted by fat-free weight ([FFW] R2 = 85%), free 3,5,3'-triiodothyronine (T3) level (R2 = 1%), and VO2max (R2 = 1%); these variables predicted RMR with a residual error of +/- 30 kcal/d. A practical equation was developed in a randomly selected subsample (N = 61) using easily measured variables as potential predictors, and was successfully cross-validated in a random subsample of older men (N = 28). The pooled equation to predict RMR is as follows: RMR (in kilocalories per day) = 9.7 (weight in kilograms) - 6.1 (chest skinfold thickness in millimeters) - 1.8 (age in years) + 0.1 (leisure time activity [LTA] in kilocalories per day) + 1,060. These variables accounted for 76% (R2) of the variation, and predicted RMR with a residual error of +/- 42 kcal/d.(ABSTRACT TRUNCATED AT 250 WORDS)
Goran, M I; Beer, W H; Wolfe, R R; Poehlman, E T; Young, V R
Variation in total energy expenditure in young healthy free-living men Journal Article
In: Metab. Clin. Exp., 42 (4), pp. 487–496, 1993.
@article{pmid8487673,
title = {Variation in total energy expenditure in young healthy free-living men},
author = {M I Goran and W H Beer and R R Wolfe and E T Poehlman and V R Young},
year = {1993},
date = {1993-00-01},
journal = {Metab. Clin. Exp.},
volume = {42},
number = {4},
pages = {487--496},
abstract = {Interindividual and intraindividual variation in total energy expenditure (TEE) were examined in 17 healthy, free-living men (weight, 56.4 to 82.4 kg; age, 18 to 30 years). TEE over 14 days, resting metabolic rate (RMR), and body composition were measured two or three times during 77 days of fixed caloric intake using doubly labeled water, respiratory gas analysis, and isotope dilution, respectively. When individual data were averaged, TEE was most significantly related to fat-free mass ([FFM] r = .73},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Interindividual and intraindividual variation in total energy expenditure (TEE) were examined in 17 healthy, free-living men (weight, 56.4 to 82.4 kg; age, 18 to 30 years). TEE over 14 days, resting metabolic rate (RMR), and body composition were measured two or three times during 77 days of fixed caloric intake using doubly labeled water, respiratory gas analysis, and isotope dilution, respectively. When individual data were averaged, TEE was most significantly related to fat-free mass ([FFM] r = .73
A practical equation to predict resting metabolic rate in older females Journal Article
In: J Am Geriatr Soc, 41 (4), pp. 389–395, 1993.
@article{pmid8463525,
title = {A practical equation to predict resting metabolic rate in older females},
year = {1993},
date = {1993-00-01},
journal = {J Am Geriatr Soc},
volume = {41},
number = {4},
pages = {389--395},
abstract = {To develop a practical and accurate age-specific equation for predicting resting metabolic rate (RMR) in older women and, thereafter, to cross-validate existing equations for predicting RMR in older females. Cross-sectional validation study. General Clinical Research Center. A convenience sample of 75 healthy older women (age 50-81) free of significant cardiovascular or any other non-cardiac disease that may affect cardiovascular function or metabolic rate. All 75 volunteers were characterized for resting metabolic rate (RMR), body composition, anthropometrics, physical activity, and energy intake. A practical equation for predicting RMR in older women using easily measured variables was: [RMR (kcal/d) = 7.8 (weight,kg) + 4.7 (standing height, cm) -39.5 (menopausal status; 1-3) + 143.5]. These variables accounted for 59% (R2) of the variation in RMR and predicted RMR within +/- 66 kcal/d. When five previously published equations were applied to our sample of older women to predict RMR, individual predicted values deviated by -31% to 20% from the measured value. We offer a practical equation to predict RMR in healthy older women based on a measure of body weight, standing height, and menopausal status.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
To develop a practical and accurate age-specific equation for predicting resting metabolic rate (RMR) in older women and, thereafter, to cross-validate existing equations for predicting RMR in older females. Cross-sectional validation study. General Clinical Research Center. A convenience sample of 75 healthy older women (age 50-81) free of significant cardiovascular or any other non-cardiac disease that may affect cardiovascular function or metabolic rate. All 75 volunteers were characterized for resting metabolic rate (RMR), body composition, anthropometrics, physical activity, and energy intake. A practical equation for predicting RMR in older women using easily measured variables was: [RMR (kcal/d) = 7.8 (weight,kg) + 4.7 (standing height, cm) -39.5 (menopausal status; 1-3) + 143.5]. These variables accounted for 59% (R2) of the variation in RMR and predicted RMR within +/- 66 kcal/d. When five previously published equations were applied to our sample of older women to predict RMR, individual predicted values deviated by -31% to 20% from the measured value. We offer a practical equation to predict RMR in healthy older women based on a measure of body weight, standing height, and menopausal status.
1992
Goran, M I; Poehlman, E T
Endurance training does not enhance total energy expenditure in healthy elderly persons Journal Article
In: Am. J. Physiol., 263 (5 Pt 1), pp. E950–957, 1992.
@article{pmid1443128,
title = {Endurance training does not enhance total energy expenditure in healthy elderly persons},
author = {M I Goran and E T Poehlman},
year = {1992},
date = {1992-11-01},
journal = {Am. J. Physiol.},
volume = {263},
number = {5 Pt 1},
pages = {E950--957},
abstract = {Physical exercise is prescribed to older individuals to increase cardiovascular fitness and improve body composition. However, there is limited information on the effect of exercise on total energy expenditure (TEE) and its components. We therefore determined the effects of short-term endurance training in 11 elderly volunteers (56-78 years) on changes in 1) TEE, from doubly labeled water; 2) resting metabolic rate (RMR), from respiratory gas analysis, 3) the energy expenditure of physical activity (EEPA), aside from that associated with the training program, and 4) body composition from a combination of body density with total body water. Endurance training increased maximum oxygen consumption (VO2max) by 9% (2.00 +/- 0.67 to 2.17 +/- 0.64 l/min; P < 0.05) and RMR by 11% (1,596 +/- 214 to 1,763 +/- 170 kcal/day; P < 0.01). There was no significant change in TEE (2,408 +/- 478 to 2,479 +/- 497 kcal/day) before and during the last 10 days of endurance training because of a 62% reduction in EEPA (571 +/- 386 to 340 +/- 452 kcal/day; P < 0.01). There was no change in body mass, but fat mass decreased (21.6 +/- 6.6 to 20.7 +/- 6.6 kg; P < 0.05). The increase in fat-free mass (49.5 +/- 9.0 to 50.4 +/- 9.1 kg; P < 0.05) was explained by an increase in body water (35.9 +/- 6.5 to 36.8 +/- 6.3 kg; P < 0.05). We conclude that in healthy elderly persons, endurance training enhances cardiovascular fitness, but does not increase TEE because of a compensatory decline in physical activity during the remainder of the day.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Physical exercise is prescribed to older individuals to increase cardiovascular fitness and improve body composition. However, there is limited information on the effect of exercise on total energy expenditure (TEE) and its components. We therefore determined the effects of short-term endurance training in 11 elderly volunteers (56-78 years) on changes in 1) TEE, from doubly labeled water; 2) resting metabolic rate (RMR), from respiratory gas analysis, 3) the energy expenditure of physical activity (EEPA), aside from that associated with the training program, and 4) body composition from a combination of body density with total body water. Endurance training increased maximum oxygen consumption (VO2max) by 9% (2.00 +/- 0.67 to 2.17 +/- 0.64 l/min; P < 0.05) and RMR by 11% (1,596 +/- 214 to 1,763 +/- 170 kcal/day; P < 0.01). There was no significant change in TEE (2,408 +/- 478 to 2,479 +/- 497 kcal/day) before and during the last 10 days of endurance training because of a 62% reduction in EEPA (571 +/- 386 to 340 +/- 452 kcal/day; P < 0.01). There was no change in body mass, but fat mass decreased (21.6 +/- 6.6 to 20.7 +/- 6.6 kg; P < 0.05). The increase in fat-free mass (49.5 +/- 9.0 to 50.4 +/- 9.1 kg; P < 0.05) was explained by an increase in body water (35.9 +/- 6.5 to 36.8 +/- 6.3 kg; P < 0.05). We conclude that in healthy elderly persons, endurance training enhances cardiovascular fitness, but does not increase TEE because of a compensatory decline in physical activity during the remainder of the day.
Poehlman, E T; Gardner, A W; Goran, M I
Influence of endurance training on energy intake, norepinephrine kinetics, and metabolic rate in older individuals Journal Article
In: Metab. Clin. Exp., 41 (9), pp. 941–948, 1992.
@article{pmid1518423,
title = {Influence of endurance training on energy intake, norepinephrine kinetics, and metabolic rate in older individuals},
author = {E T Poehlman and A W Gardner and M I Goran},
year = {1992},
date = {1992-09-01},
journal = {Metab. Clin. Exp.},
volume = {41},
number = {9},
pages = {941--948},
abstract = {The role of physical activity in the regulation of energy intake in older persons is presently unclear. We therefore examined the influence of endurance training on voluntary energy intake and the associated changes in resting metabolic rate (RMR) and norepinephrine (NE) kinetics in seven healthy (six men, one woman) older individuals (69.4 +/- 2.2 years) under supervised living conditions. Energy intake was measured by covert assessment in a clinical research environment during: (1) a 10-day inpatient control period (no exercise); (2) a 10-day light exercise period (150 kcal per session, 3 times/wk); and (3) a 10-day moderate exercise period (300 kcal per session, 3 times/wk). RMR was determined after all three periods, and NE kinetics were assessed before and after training by infusions of tritiated NE ([3H]-NE). No significant change in energy intake was found between the control (2,378 +/- 130 kcal/d) and light exercise (2,449 +/- 104 kcal/d) periods, whereas energy intake increased 17% (P less than .01) during moderate exercise (2,785 +/- 161 kcal/d). Changes in RMR paralleled those of energy intake, as no differences were noted in RMR after control (1.03 +/- 0.12 kcal/min) and light exercise periods (1.04 +/- 0.12 kcal/min), but RMR increased 9% (1.13 +/- 0.14 kcal/min, P less than .01) after moderate endurance training, despite no changes in body composition.(ABSTRACT TRUNCATED AT 250 WORDS)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The role of physical activity in the regulation of energy intake in older persons is presently unclear. We therefore examined the influence of endurance training on voluntary energy intake and the associated changes in resting metabolic rate (RMR) and norepinephrine (NE) kinetics in seven healthy (six men, one woman) older individuals (69.4 +/- 2.2 years) under supervised living conditions. Energy intake was measured by covert assessment in a clinical research environment during: (1) a 10-day inpatient control period (no exercise); (2) a 10-day light exercise period (150 kcal per session, 3 times/wk); and (3) a 10-day moderate exercise period (300 kcal per session, 3 times/wk). RMR was determined after all three periods, and NE kinetics were assessed before and after training by infusions of tritiated NE ([3H]-NE). No significant change in energy intake was found between the control (2,378 +/- 130 kcal/d) and light exercise (2,449 +/- 104 kcal/d) periods, whereas energy intake increased 17% (P less than .01) during moderate exercise (2,785 +/- 161 kcal/d). Changes in RMR paralleled those of energy intake, as no differences were noted in RMR after control (1.03 +/- 0.12 kcal/min) and light exercise periods (1.04 +/- 0.12 kcal/min), but RMR increased 9% (1.13 +/- 0.14 kcal/min, P less than .01) after moderate endurance training, despite no changes in body composition.(ABSTRACT TRUNCATED AT 250 WORDS)
Goran, M I; Poehlman, E T
Total energy expenditure and energy requirements in healthy elderly persons Journal Article
In: Metab. Clin. Exp., 41 (7), pp. 744–753, 1992.
@article{pmid1619993,
title = {Total energy expenditure and energy requirements in healthy elderly persons},
author = {M I Goran and E T Poehlman},
year = {1992},
date = {1992-07-01},
journal = {Metab. Clin. Exp.},
volume = {41},
number = {7},
pages = {744--753},
abstract = {To investigate energy requirements in healthy elderly subjects, we assessed the association of total energy expenditure (TEE) with resting metabolic rate (RMR), physical activity, body composition, and energy intake in 13 individuals (aged 56 to 78 years, six women and seven men). Free-living TEE was measured using doubly labeled water, RMR was measured by respiratory gas analysis, and energy expenditure of physical activity (EEPA) was derived from the difference between TEE and RMR, assuming the thermic response to feeding contributes 10% of TEE. Fat mass (FM) and fat-free mass (FFM) were obtained from underwater weighing, VO2max was determined from a bicycle test to exhaustion, energy intake was obtained from a 3-day food diary, and leisure time activity (LTA) was determined by structured interview. TEE was 2,406 +/- 438 kcal/d (range, 1,856 to 3,200 kcal/d, or 1.25 to 2.11 times RMR) and was related to VO2max (r = .79},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
To investigate energy requirements in healthy elderly subjects, we assessed the association of total energy expenditure (TEE) with resting metabolic rate (RMR), physical activity, body composition, and energy intake in 13 individuals (aged 56 to 78 years, six women and seven men). Free-living TEE was measured using doubly labeled water, RMR was measured by respiratory gas analysis, and energy expenditure of physical activity (EEPA) was derived from the difference between TEE and RMR, assuming the thermic response to feeding contributes 10% of TEE. Fat mass (FM) and fat-free mass (FFM) were obtained from underwater weighing, VO2max was determined from a bicycle test to exhaustion, energy intake was obtained from a 3-day food diary, and leisure time activity (LTA) was determined by structured interview. TEE was 2,406 +/- 438 kcal/d (range, 1,856 to 3,200 kcal/d, or 1.25 to 2.11 times RMR) and was related to VO2max (r = .79
Berke, E M; Gardner, A W; Goran, M I; Poehlman, E T
Resting metabolic rate and the influence of the pretesting environment Journal Article
In: Am. J. Clin. Nutr., 55 (3), pp. 626–629, 1992.
@article{pmid1550034,
title = {Resting metabolic rate and the influence of the pretesting environment},
author = {E M Berke and A W Gardner and M I Goran and E T Poehlman},
year = {1992},
date = {1992-03-01},
journal = {Am. J. Clin. Nutr.},
volume = {55},
number = {3},
pages = {626--629},
abstract = {We examined the effect of pretesting environment on measurement of resting metabolic rate (RMR). RMR was measured in 18 older (66.1 +/- 1.4 y) individuals after an overnight stay in the Clinical Research Center (ie, inpatient) and after subjects transported themselves to the laboratory (ie, outpatient). Similar measurements were also performed after an 8-wk endurance-training program. RMR was higher (P less than 0.01) before exercise training in subjects who transported themselves to the laboratory (ie, outpatients; 4.9 +/- 0.13 kJ/min) than in inpatients (4.6 +/- 0.13 kJ/min) and after exercise training in outpatients (5.4 +/- 0.08 kJ/min) vs inpatients (5.0 +/- 0.13 kJ/min). Training increased RMR under both inpatient (10%; P less than 0.01) and outpatient (11%; P less than 0.01) conditions. We conclude that RMR is higher when measured under outpatient conditions in older volunteers. Therefore, when daily energy requirements based on the assessment of RMR are being estimated, the pretesting environment should be considered. However, the exercise-training-induced increase in RMR can be detected by using either an inpatient or an outpatient protocol.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We examined the effect of pretesting environment on measurement of resting metabolic rate (RMR). RMR was measured in 18 older (66.1 +/- 1.4 y) individuals after an overnight stay in the Clinical Research Center (ie, inpatient) and after subjects transported themselves to the laboratory (ie, outpatient). Similar measurements were also performed after an 8-wk endurance-training program. RMR was higher (P less than 0.01) before exercise training in subjects who transported themselves to the laboratory (ie, outpatients; 4.9 +/- 0.13 kJ/min) than in inpatients (4.6 +/- 0.13 kJ/min) and after exercise training in outpatients (5.4 +/- 0.08 kJ/min) vs inpatients (5.0 +/- 0.13 kJ/min). Training increased RMR under both inpatient (10%; P less than 0.01) and outpatient (11%; P less than 0.01) conditions. We conclude that RMR is higher when measured under outpatient conditions in older volunteers. Therefore, when daily energy requirements based on the assessment of RMR are being estimated, the pretesting environment should be considered. However, the exercise-training-induced increase in RMR can be detected by using either an inpatient or an outpatient protocol.
Goran, M I; Poehlman, E T; Nair, K S; Danforth, E
Effect of gender, body composition, and equilibration time on the 2Ħ-to-18O dilution space ratio Journal Article
In: Am. J. Physiol., 263 (6), pp. E1119–1124, 1992.
@article{pmid1476185,
title = {Effect of gender, body composition, and equilibration time on the 2Ħ-to-18O dilution space ratio},
author = {M I Goran and E T Poehlman and K S Nair and E Danforth},
year = {1992},
date = {1992-01-01},
journal = {Am. J. Physiol.},
volume = {263},
number = {6},
pages = {E1119--1124},
abstract = {Physiological sources of variation in the 2H-to-18O dilution space ratio (DSR) were examined in 34 males and 20 females (4-78 yr; 14.7-143.2 kg; 1.8-61.0% body fat). Dilution spaces were obtained by time 0 extrapolation of isotope washout over 10-14 days, and body composition was obtained by underwater weight (adults) or bioelectrical impedance (children). The mean DSR was 1.050 +/- 0.015 (range 1.029-1.111), significantly higher (P < 0.001) than the traditionally assumed value of 1.029 based on exchange over 4 h. Use of the value 1.029 causes a systematic 8% overestimate of energy expenditure from doubly labeled water, relative to use of the value 1.05. The DSR was not related to body composition or age but was significantly higher (P < 0.05) in males (1.052 +/- 0.016) than in females (1.044 +/- 0.012). This gender effect was not explained by differences in the number of exchangeable hydrogens in the body. We conclude 1) variation in the 2H-to-18O DSR is not explained by body composition but is influenced by the chemical availability of exchangeable hydrogens to undergo exchange; 2) because the DSR is not easily predicted, use of the observed dilution spaces are recommended; 3) if a fixed DSR is used, values of 1.044 and 1.052 are recommended in females and males, respectively.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Physiological sources of variation in the 2H-to-18O dilution space ratio (DSR) were examined in 34 males and 20 females (4-78 yr; 14.7-143.2 kg; 1.8-61.0% body fat). Dilution spaces were obtained by time 0 extrapolation of isotope washout over 10-14 days, and body composition was obtained by underwater weight (adults) or bioelectrical impedance (children). The mean DSR was 1.050 +/- 0.015 (range 1.029-1.111), significantly higher (P < 0.001) than the traditionally assumed value of 1.029 based on exchange over 4 h. Use of the value 1.029 causes a systematic 8% overestimate of energy expenditure from doubly labeled water, relative to use of the value 1.05. The DSR was not related to body composition or age but was significantly higher (P < 0.05) in males (1.052 +/- 0.016) than in females (1.044 +/- 0.012). This gender effect was not explained by differences in the number of exchangeable hydrogens in the body. We conclude 1) variation in the 2H-to-18O DSR is not explained by body composition but is influenced by the chemical availability of exchangeable hydrogens to undergo exchange; 2) because the DSR is not easily predicted, use of the observed dilution spaces are recommended; 3) if a fixed DSR is used, values of 1.044 and 1.052 are recommended in females and males, respectively.
Poehlman, E T; Berke, E M; Joseph, J R; Gardner, A W; Katzman-Rooks, S M; Goran, M I
Influence of aerobic capacity, body composition, and thyroid hormones on the age-related decline in resting metabolic rate Journal Article
In: Metab. Clin. Exp., 41 (8), pp. 915–921, 1992.
@article{pmid1640872,
title = {Influence of aerobic capacity, body composition, and thyroid hormones on the age-related decline in resting metabolic rate},
author = {E T Poehlman and E M Berke and J R Joseph and A W Gardner and S M Katzman-Rooks and M I Goran},
year = {1992},
date = {1992-00-01},
journal = {Metab. Clin. Exp.},
volume = {41},
number = {8},
pages = {915--921},
abstract = {It has been suggested that changes in fat-free weight may not fully explain the decline of resting metabolic rate (RMR) that occurs with aging. We therefore examined the hypothesis that a reduction in maximal aerobic capacity (VO2max) may partially explain the lower RMR in older men, after accounting for differences in fat-free weight and fat weight. We also considered differences in energy intake and plasma thyroid hormones as possible modulators of the age-related decline in RMR in men. Three-hundred healthy men (aged 17 to 78 years) were characterized for: (1) RMR (kcal/min) from indirect calorimetry; (2) body composition from underwater weighing; (3) maximal aerobic capacity from a test of VO2max; (4) plasma thyroid hormones (total triiodothyronine [T3], free T3, total thyroxine [T4], and free T4); and (5) estimated energy intake (kcal/d) from a 3-day food diary. A curvilinear decline of RMR with age was found (P less than .01), in which no relationship was found in men less than 40 years of age (r = .10},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
It has been suggested that changes in fat-free weight may not fully explain the decline of resting metabolic rate (RMR) that occurs with aging. We therefore examined the hypothesis that a reduction in maximal aerobic capacity (VO2max) may partially explain the lower RMR in older men, after accounting for differences in fat-free weight and fat weight. We also considered differences in energy intake and plasma thyroid hormones as possible modulators of the age-related decline in RMR in men. Three-hundred healthy men (aged 17 to 78 years) were characterized for: (1) RMR (kcal/min) from indirect calorimetry; (2) body composition from underwater weighing; (3) maximal aerobic capacity from a test of VO2max; (4) plasma thyroid hormones (total triiodothyronine [T3], free T3, total thyroxine [T4], and free T4); and (5) estimated energy intake (kcal/d) from a 3-day food diary. A curvilinear decline of RMR with age was found (P less than .01), in which no relationship was found in men less than 40 years of age (r = .10
1991
Goran, M I; Broemeling, L; Herndon, D N; Peters, E J; Wolfe, R R
Estimating energy requirements in burned children: a new approach derived from measurements of resting energy expenditure Journal Article
In: Am. J. Clin. Nutr., 54 (1), pp. 35–40, 1991.
@article{pmid2058584,
title = {Estimating energy requirements in burned children: a new approach derived from measurements of resting energy expenditure},
author = {M I Goran and L Broemeling and D N Herndon and E J Peters and R R Wolfe},
year = {1991},
date = {1991-07-01},
journal = {Am. J. Clin. Nutr.},
volume = {54},
number = {1},
pages = {35--40},
abstract = {We examined the determinants of resting energy expenditure (REE) in 127 observations in 56 burned children. Predicted basal energy expenditure (PBEE), body surface area (BSA), and body weight correlated significantly with REE (r2 = 0.76). Days postburn and burn size (% BSA burned) only accounted for 21%, and 24% of the variation in the elevation in REE above PBEE. The single most powerful predictor of REE was PBEE (REE = 1.29 x PBEE); addition of other variables did not improve the prediction. When our recently described activity factor of 1.2 for burn patients is used, the data predict that the average energy requirement to maintain energy balance is 1.55 x PBEE, which is significantly lower than commonly used recommendations, especially for larger burns. The energy required to ensure that 95% of patients achieve energy balance was (1.55 x PBEE) + (2.39 xoff+PBEE0.75), approximately equal to 2 x PBEE. Because the equations presented are derived from measurements of energy expenditure, they represent the most valid approach to estimating energy requirements.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We examined the determinants of resting energy expenditure (REE) in 127 observations in 56 burned children. Predicted basal energy expenditure (PBEE), body surface area (BSA), and body weight correlated significantly with REE (r2 = 0.76). Days postburn and burn size (% BSA burned) only accounted for 21%, and 24% of the variation in the elevation in REE above PBEE. The single most powerful predictor of REE was PBEE (REE = 1.29 x PBEE); addition of other variables did not improve the prediction. When our recently described activity factor of 1.2 for burn patients is used, the data predict that the average energy requirement to maintain energy balance is 1.55 x PBEE, which is significantly lower than commonly used recommendations, especially for larger burns. The energy required to ensure that 95% of patients achieve energy balance was (1.55 x PBEE) + (2.39 xoff+PBEE0.75), approximately equal to 2 x PBEE. Because the equations presented are derived from measurements of energy expenditure, they represent the most valid approach to estimating energy requirements.
Poehlman, E T; Melby, C L; Goran, M I
The impact of exercise and diet restriction on daily energy expenditure Journal Article
In: Sports Med, 11 (2), pp. 78–101, 1991.
@article{pmid2017606,
title = {The impact of exercise and diet restriction on daily energy expenditure},
author = {E T Poehlman and C L Melby and M I Goran},
year = {1991},
date = {1991-02-01},
journal = {Sports Med},
volume = {11},
number = {2},
pages = {78--101},
abstract = {In addition to the direct energy cost of physical activity, exercise may influence resting energy expenditure in 3 ways: (a) a prolonged increase in postexercise metabolic rate from an acute exercise challenge; (b) a chronic increase in resting metabolic rate associated with exercise training; and (c) a possible increase in energy expenditure during nonexercising time. It seems apparent that the greater the exercise perturbation, the greater the magnitude of the increase in postexercise metabolic rate. An exercise prescription for the general population that consists of exercise of low (less than 50% VO2max) or moderate intensity (50 to 75% VO2max) does not appear to produce a prolonged elevation of postexercise metabolic rate that would influence body-weight. Inconsistent results have been found with respect to the effects of exercise training and the trained state on resting metabolic rate. Whereas some investigators have found a higher resting metabolic rate in trained than untrained individuals and in individuals after an exercise training programme, other investigators have found no chronic exercise effect on resting metabolic rate. Differences in experimental design, genetic variation and alterations in energy balance may contribute to the discrepant findings among investigators. A relatively unexplored area concerns the influence of exercise training on energy expenditure during nonexercising time. It is presently unclear whether exercise training increases or decreases the energy expenditure associated with spontaneous or nonpurposeful physical activity which includes fidgeting, muscular activity, etc. The doubly labelled water technique represents a methodological advance in this area and permits the determination of total daily energy expenditure. Concomitant with the determination of the other components of daily energy expenditure (resting metabolic rate and thermic effect of a meal), it will now be possible to examine the adaptive changes in energy expenditure during nonexercising time. A plethora of studies have examined the combined effects of diet and exercise on body composition and resting metabolic rate. The hypothesis is that combining diet and exercise will accelerate fat loss, preserve fat-free weight and prevent or decelerate the decline in resting metabolic rate more effectively than with diet restriction alone. The optimal combination of diet and exercise, however, remains elusive. It appears that the combination of a large quantity of aerobic exercise with a very low calorie diet resulting in substantial loss of bodyweight may actually accelerate the decline in resting metabolic rate. These findings may cause us to re-examine the quantity of exercise and diet needed to achieve optimal fat loss and preservation of resting metabolic rate.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In addition to the direct energy cost of physical activity, exercise may influence resting energy expenditure in 3 ways: (a) a prolonged increase in postexercise metabolic rate from an acute exercise challenge; (b) a chronic increase in resting metabolic rate associated with exercise training; and (c) a possible increase in energy expenditure during nonexercising time. It seems apparent that the greater the exercise perturbation, the greater the magnitude of the increase in postexercise metabolic rate. An exercise prescription for the general population that consists of exercise of low (less than 50% VO2max) or moderate intensity (50 to 75% VO2max) does not appear to produce a prolonged elevation of postexercise metabolic rate that would influence body-weight. Inconsistent results have been found with respect to the effects of exercise training and the trained state on resting metabolic rate. Whereas some investigators have found a higher resting metabolic rate in trained than untrained individuals and in individuals after an exercise training programme, other investigators have found no chronic exercise effect on resting metabolic rate. Differences in experimental design, genetic variation and alterations in energy balance may contribute to the discrepant findings among investigators. A relatively unexplored area concerns the influence of exercise training on energy expenditure during nonexercising time. It is presently unclear whether exercise training increases or decreases the energy expenditure associated with spontaneous or nonpurposeful physical activity which includes fidgeting, muscular activity, etc. The doubly labelled water technique represents a methodological advance in this area and permits the determination of total daily energy expenditure. Concomitant with the determination of the other components of daily energy expenditure (resting metabolic rate and thermic effect of a meal), it will now be possible to examine the adaptive changes in energy expenditure during nonexercising time. A plethora of studies have examined the combined effects of diet and exercise on body composition and resting metabolic rate. The hypothesis is that combining diet and exercise will accelerate fat loss, preserve fat-free weight and prevent or decelerate the decline in resting metabolic rate more effectively than with diet restriction alone. The optimal combination of diet and exercise, however, remains elusive. It appears that the combination of a large quantity of aerobic exercise with a very low calorie diet resulting in substantial loss of bodyweight may actually accelerate the decline in resting metabolic rate. These findings may cause us to re-examine the quantity of exercise and diet needed to achieve optimal fat loss and preservation of resting metabolic rate.
1990
Goran, M I; Peters, E J; Herndon, D N; Wolfe, R R
Total energy expenditure in burned children using the doubly labeled water technique Journal Article
In: Am. J. Physiol., 259 (4 Pt 1), pp. E576–585, 1990.
@article{pmid2171351,
title = {Total energy expenditure in burned children using the doubly labeled water technique},
author = {M I Goran and E J Peters and D N Herndon and R R Wolfe},
year = {1990},
date = {1990-00-01},
journal = {Am. J. Physiol.},
volume = {259},
number = {4 Pt 1},
pages = {E576--585},
abstract = {Total energy expenditure (TEE) was measured in 15 burned children with the doubly labeled water technique. Application of the technique in burned children required evaluation of potential errors resulting from nutritional intake altering background enrichments during studies and from the high rate of water turnover relative to CO2 production. Five studies were discarded because of these potential problems. TEE was 1.33 +/- 0.27 times predicted basal energy expenditure (BEE), and in studies where resting energy expenditure (REE) was simultaneously measured, TEE was 1.18 +/- 0.17 times REE, which in turn was 1.16 +/- 0.10 times predicted BEE. TEE was significantly correlated with measured REE (r2 = 0.92) but not with predicted BEE. These studies substantiate the advantage of measuring REE to predict TEE in severely burned patients as opposed to relying on standardized equations. Therefore we recommend that optimal nutritional support will be achieved in convalescent burned children by multiplying REE by an activity factor of 1.2.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Total energy expenditure (TEE) was measured in 15 burned children with the doubly labeled water technique. Application of the technique in burned children required evaluation of potential errors resulting from nutritional intake altering background enrichments during studies and from the high rate of water turnover relative to CO2 production. Five studies were discarded because of these potential problems. TEE was 1.33 +/- 0.27 times predicted basal energy expenditure (BEE), and in studies where resting energy expenditure (REE) was simultaneously measured, TEE was 1.18 +/- 0.17 times REE, which in turn was 1.16 +/- 0.10 times predicted BEE. TEE was significantly correlated with measured REE (r2 = 0.92) but not with predicted BEE. These studies substantiate the advantage of measuring REE to predict TEE in severely burned patients as opposed to relying on standardized equations. Therefore we recommend that optimal nutritional support will be achieved in convalescent burned children by multiplying REE by an activity factor of 1.2.
1988
Goran, M I; Little, R A; Frayn, K N; Jones, R; Fozzard, G
Effects of chronic endotoxaemia on oxygen consumption at different ambient temperatures in the unanaesthetised rat Journal Article
In: Circ. Shock, 25 (2), pp. 103–109, 1988.
@article{pmid3292075,
title = {Effects of chronic endotoxaemia on oxygen consumption at different ambient temperatures in the unanaesthetised rat},
author = {M I Goran and R A Little and K N Frayn and R Jones and G Fozzard},
year = {1988},
date = {1988-06-01},
journal = {Circ. Shock},
volume = {25},
number = {2},
pages = {103--109},
abstract = {Oxygen consumption has been measured at different ambient temperatures at intervals during the intravenous infusion of endotoxin (1 mg/kg.day-1) from a subcutaneously implanted osmotic minipump in unanaesthetised rats. On day 1 of the infusion oxygen consumption was elevated at ambient temperatures of 10, 28, and 31 degrees C but not at 20 degrees C, compared with pair-fed saline-infused controls. There was a significant negative correlation between oxygen consumption on days 1 and 3 and environmental temperature (10, 20, and 28 degrees C) in both groups, but the regression line describing the relation in endotoxin-infused rats was displaced above that for the saline-infused control without a change in slope. The "minimal observed" oxygen consumption, which is taken as an estimate of basal metabolic rate, was elevated by the infusion of endotoxin. The endotoxin-induced increase in "minimal observed" oxygen consumption was removed by indomethacin (5 mg/kg.sc) on day 1 of the infusion but was ineffective on days 3 and 7.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Oxygen consumption has been measured at different ambient temperatures at intervals during the intravenous infusion of endotoxin (1 mg/kg.day-1) from a subcutaneously implanted osmotic minipump in unanaesthetised rats. On day 1 of the infusion oxygen consumption was elevated at ambient temperatures of 10, 28, and 31 degrees C but not at 20 degrees C, compared with pair-fed saline-infused controls. There was a significant negative correlation between oxygen consumption on days 1 and 3 and environmental temperature (10, 20, and 28 degrees C) in both groups, but the regression line describing the relation in endotoxin-infused rats was displaced above that for the saline-infused control without a change in slope. The "minimal observed" oxygen consumption, which is taken as an estimate of basal metabolic rate, was elevated by the infusion of endotoxin. The endotoxin-induced increase in "minimal observed" oxygen consumption was removed by indomethacin (5 mg/kg.sc) on day 1 of the infusion but was ineffective on days 3 and 7.
Goran, M I; Frayn, K N; Little, R A
Energy metabolism during chronic endotoxin infusion in the rat, with special reference to free fatty acid turnover Journal Article
In: Circ. Shock, 25 (1), pp. 9–20, 1988.
@article{pmid3042188,
title = {Energy metabolism during chronic endotoxin infusion in the rat, with special reference to free fatty acid turnover},
author = {M I Goran and K N Frayn and R A Little},
year = {1988},
date = {1988-05-01},
journal = {Circ. Shock},
volume = {25},
number = {1},
pages = {9--20},
abstract = {We have studied various aspects of whole-body energy metabolism during chronic endotoxin infusion in the rat. In particular, we studied free fatty acid kinetics using bolus injections of 14C-palmitate. The general response to 7 days of chronic endotoxin infusion could be divided into an initial 3- to 4-day period of illness with loss of appetite, followed by rapid recovery. Using saline-infused, pair-fed controls, the following observations were made throughout the 7-day period of endotoxin infusion: 1) Plasma free fatty acids, glycerol and 3-hydroxybutyrate concentrations were reduced; 2) plasma glucose concentrations were elevated; 3) free fatty acid production rates were unaffected; 4) metabolic clearance of free fatty acids was unaffected on day 1 but was significantly greater on days 3 and 7; 5) haematocrits and plasma volumes were elevated. The results suggest that the observed changes in circulating free fatty acid concentrations are more likely to be a consequence of haemodynamic alterations than of metabolic alterations.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We have studied various aspects of whole-body energy metabolism during chronic endotoxin infusion in the rat. In particular, we studied free fatty acid kinetics using bolus injections of 14C-palmitate. The general response to 7 days of chronic endotoxin infusion could be divided into an initial 3- to 4-day period of illness with loss of appetite, followed by rapid recovery. Using saline-infused, pair-fed controls, the following observations were made throughout the 7-day period of endotoxin infusion: 1) Plasma free fatty acids, glycerol and 3-hydroxybutyrate concentrations were reduced; 2) plasma glucose concentrations were elevated; 3) free fatty acid production rates were unaffected; 4) metabolic clearance of free fatty acids was unaffected on day 1 but was significantly greater on days 3 and 7; 5) haematocrits and plasma volumes were elevated. The results suggest that the observed changes in circulating free fatty acid concentrations are more likely to be a consequence of haemodynamic alterations than of metabolic alterations.
0000
Aris Plows JF, IM
Associations of Maternal Non-Nutritive Sweetener Intake During Pregnancy with Offspring Boddy Mass Index and Body Fat From Birth to Adolescence Int J Obesity Journal Article Forthcoming
In: Forthcoming.
BibTeX | Tags:
@article{nokey,
title = {Associations of Maternal Non-Nutritive Sweetener Intake During Pregnancy with Offspring Boddy Mass Index and Body Fat From Birth to Adolescence Int J Obesity},
author = {Plows JF, Aris, IM, Rifas-Shiman SL, Goran MI & Oken E },
keywords = {},
pubstate = {forthcoming},
tppubtype = {article}
}
Glasson J Patterson WB, Naik N
Prenatal Exposure to Ambient Air Pollutants and Early Infant Growth and Adiposity in the Southern California Mother’s Milk Study Environmental Health Journal Article Forthcoming
In: Forthcoming.
BibTeX | Tags:
@article{nokey,
title = {Prenatal Exposure to Ambient Air Pollutants and Early Infant Growth and Adiposity in the Southern California Mother’s Milk Study Environmental Health},
author = {Patterson WB, Glasson J, Naik N, Kazemian E, Jones RB, Berger PK, Plows JF, Minor HA, Lurmann F, Goran MI & Alderete TL },
keywords = {},
pubstate = {forthcoming},
tppubtype = {article}
}
