Air displacement plethysmography can detect moderate changes in body composition

OBJECTIVES: To determine the sensitivity of air displacement plethysmography (APD) for evaluation of changes in body composition in normal subjects. DESIGN: Comparison of measurements with and without oil or water loads. SUBJECTS AND METHODS: Ten healthy volunteers were analyzed, without and with 1 l and 2 l of oil or water. The measured and true changes in fat mass and fat-free mass were compared by paired t-tests. A correlation study and a Bland & Altman procedure was performed on the 60 measurements of adiposity changes in 30 subjects carrying 0.5 l (n=8 x 2), 1 l (n=10 x 2) and 2 l (n=12 x 2) oil and water loads. RESULTS: Fat-free mass increased when the 10 subjects were carrying water. When they carried oil, fat mass increased, however, a approximately 0.5 kg increase of fat-free mass was also detected. Two liters loads led to distinct changes: +1.49+/-0.59 kg fat and +0.50+/-0.60 kg fat-free with oil and +0.37+/-0.57 kg fat and +1.70+/-0.56 kg fat-free with water (both P<0.001). Mixed loads (+1 l oil and 1 l water) led to detect +0.85+/-0.48 kg fat and +1.09+/-0.45 kg fat-free (both P<0.005 vs without load). For the 30 subjects analyzed thrice, measured changes in fat and fat-free mass were slightly underestimated (-15%, NS) but correlated with the true changes. Measured changes in adiposity were correlated with the true changes, with no bias as indicated by the Bland & Altman procedure. CONCLUSION: APD detects approximately 2 kg changes in fat or fat-free mass in small populations.     

Bioelectrical impedance analysis during acute changes of extracellular osmolality in man

BACKGROUND & AIMS: Bioelectrical impedance analysis (BIA) is widely used as an inexpensive and noninvasive method to provide estimates of body compartments such as total body water, lean body mass and fat mass. The present study was performed to test the reliability of this method during acute changes of extracellular osmolality in eight young health men. METHODS: Hyperosmolal isohydration was achieved by overnight infusions of hypertonic saline solutions (2 and 5% NaCl) and thirsting, and hypoosmolal hyperhydration by drinking of free water and overnight application of desmopressin. The control study (isoosmolality) consisted of oral water ad libitum. RESULTS: When plasma osmolality and sodium concentrations increased (from 285 +/- 1 to 296 +/- 1 mmol/kg (P<0.001) and from 141.9 +/- 0.7 to 148.3 +/- 0.6 mmol/l (P<0.0001)) and total body water remained unchanged, body impedance decreased and calculated total body water increased from 42.7 +/- 2.7 to 45.6 +/- 2.3 liters (P<0.03). In contrast, during hypoosmolal hyperhydration total body water increased by 1.56 +/- 0.17 kg and plasma osmolality decreased from 285 +/- 1 to 272 +/- 1 mmol/kg (P<0.001) and plasma sodium concentrations from 142 +/- 0.5 to 134.8 +/- 0.4 mmol/l (P<0.0001). In spite of these changes of body water, impedance measurements and calculated total body water remained unchanged. During conditions of isoosmolal isohydration (as demonstrated by unchanged plasma sodium concentrations and osmolality) the measurements by BIA also remained unchanged. CONCLUSIONS: Measurements of total body water using BIA under conditions of unknown hydration status (hyper-, hypo- or isohydration) and unknown osmolality (hyper-, hypo- or isoosmolality) may not be reliable. Therefore bioelectrical impedance analysis is not a suitable bedside method to assess changes of body compartments under unstable hydration status.     

The effects of a 20-week exercise training program on resting metabolic rate in previously sedentary, moderately obese women

The present study was designed to investigate the effects of exercise training on resting metabolic rate (RMR) in moderately obese women. It was hypothesized that exercise training would increase resting metabolic rate. Nineteen previously sedentary, moderately obese women (age = 38.0 +/- 0.9 years, percent body fat = 37.5 +/- 0.8) trained for 20 weeks using either resistance training (RT) or a combination of resistance training and walking (RT/W). The high intensity resistance-training program was designed to increase strength and fat-free mass and the walking program to increase aerobic capacity. There was also a non-exercising control group (C) of 9 subjects in this study. Fat-free mass was significantly increased in both the RT (+1.90 kg) and RT/W (+1.90 kg) groups as a result of the training program. No group showed significant changes in fat mass or relative body fat from pre- to post-training. Aerobic capacity was slightly, though significantly, increased in the RT/W group only. The RT group showed a significant increase (+44 kcal x day(-1)), while the RT/W group showed a significant decrease (-53 kcal x day(-1)) in resting metabolic rate post-training. RT can potentiate an increase in RMR through an increase in fat-free mass, and the decrease in RMR in the RT/W group may have been a result of heat acclimation from the walk training.     

Liver volume and visceral obesity in women with hepatic steatosis undergoing gastric banding

OBJECTIVE: To investigate the relationships between visceral obesity and hepatic steatosis in obese patients undergoing adjustable silicone gastric banding with the LAP-BAND. RESEARCH METHODS AND PROCEDURES: Six premenopausal, morbidly obese women with an ultrasonographic diagnosis of liver steatosis were evaluated before surgery and 8 and 24 weeks after surgery. Liver volume and body fat distribution were simultaneously analyzed by total-body multislices magnetic resonance imaging. RESULTS: Before surgery, the only variable found to be correlated with liver volume was visceral adipose tissue volume (r = 0.91; p < 0.01). Weight loss was 9.9 +/- 3.8 kg in the period from 0 to 8 weeks (p < 0.01) and 7.1 +/- 4.9 kg in the the period from 8 to 24 weeks (p < 0.05). Total fat showed a statistically significant reduction of 6.2 +/- 4.0 liters in the 0- to 8-week period and a further significant reduction of 7.7 +/- 3.9 liters in the 8- to 24-week period. Visceral adipose tissue showed a statistically significant reduction of 1.0 +/- 0.9 liters in the 0- to 8-week period (p < 0.05) but only a further, not significant reduction of 0.6 +/- 0.7 liters in the 8- to 24-week period. The relative reduction of visceral fat in the 0-to 8-week period was higher than the relative reduction of total fat. Liver volume also showed a statistically significant reduction of 0.24 +/- 0.26 liters in the first phase of weight loss (p < 0.05), corresponding to a relative reduction of 12.3 +/- 10.6%. During the 8- to 24-week period, liver volume was substantially stable. DISCUSSION: Hepatomegaly was associated with visceral obesity in morbidly obese women with liver steatosis. In the phase of rapid weight loss after gastric surgery, a preferential mobilization of visceral fat, compared with total adipose tissue, occurred. This preferential visceral fat loss was associated with a significant reduction in liver volume.     

Comparison of methods for assessing body-composition changes over 1 y in postmenopausal women

BACKGROUND: Advances in dual-energy X-ray absorptiometry (DXA) software algorithms have improved the accuracy of this method for body-composition measurement. OBJECTIVE: Our objective was to compare the utility of DXA, underwater weighing (UWW), and a multicomponent model (MC) for assessing changes in body composition. DESIGN:: Previously sedentary women aged 40-66 y were randomly assigned to exercise training (ET; n = 36) and no exercise training (NT; n = 40). ET subjects exercised 3 d/wk; NT subjects remained sedentary. Changes in body mass, fat mass, and fat-free mass over 1 y were assessed by the 3 methods. RESULTS: Correlations among methods were significant and large (0.73-0.97). Body weight did not change significantly in either group. In the ET group, fat-free mass increased significantly as assessed by DXA (0.7 +/- 1.0 kg) but changes assessed by MC and UWW were not significant. Changes in fat mass and percentage body fat in the ET group were not significant. SDs for changes in fat mass and percentage body fat, respectively, from DXA were 2.5 kg and 2.7%; for MC, 5.5 kg and 7.1%; and for UWW, 4.4 kg and 5.8%. In the NT group, changes in fat-free mass, fat mass, and percentage body fat were significant (P 相似文献   

Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women

OBJECTIVE: To compare the effects of isocaloric, energy-restricted very low-carbohydrate ketogenic (VLCK) and low-fat (LF) diets on weight loss, body composition, trunk fat mass, and resting energy expenditure (REE) in overweight/obese men and women. DESIGN: Randomized, balanced, two diet period clinical intervention study. Subjects were prescribed two energy-restricted (-500 kcal/day) diets: a VLCK diet with a goal to decrease carbohydrate levels below 10% of energy and induce ketosis and a LF diet with a goal similar to national recommendations (%carbohydrate:fat:protein = ~60:25:15%). SUBJECTS: 15 healthy, overweight/obese men (mean +/- s.e.m.: age 33.2 +/- 2.9 y, body mass 109.1 +/- 4.6 kg, body mass index 34.1 +/- 1.1 kg/m2) and 13 premenopausal women (age 34.0 +/- 2.4 y, body mass 76.3 +/- 3.6 kg, body mass index 29.6 +/- 1.1 kg/m2). MEASUREMENTS: Weight loss, body composition, trunk fat (by dual-energy X-ray absorptiometry), and resting energy expenditure (REE) were determined at baseline and after each diet intervention. Data were analyzed for between group differences considering the first diet phase only and within group differences considering the response to both diets within each person. RESULTS: Actual nutrient intakes from food records during the VLCK (%carbohydrate:fat:protein = ~9:63:28%) and the LF (~58:22:20%) were significantly different. Dietary energy was restricted, but was slightly higher during the VLCK (1855 kcal/day) compared to the LF (1562 kcal/day) diet for men. Both between and within group comparisons revealed a distinct advantage of a VLCK over a LF diet for weight loss, total fat loss, and trunk fat loss for men (despite significantly greater energy intake). The majority of women also responded more favorably to the VLCK diet, especially in terms of trunk fat loss. The greater reduction in trunk fat was not merely due to the greater total fat loss, because the ratio of trunk fat/total fat was also significantly reduced during the VLCK diet in men and women. Absolute REE (kcal/day) was decreased with both diets as expected, but REE expressed relative to body mass (kcal/kg), was better maintained on the VLCK diet for men only. Individual responses clearly show the majority of men and women experience greater weight and fat loss on a VLCK than a LF diet. CONCLUSION: This study shows a clear benefit of a VLCK over LF diet for short-term body weight and fat loss, especially in men. A preferential loss of fat in the trunk region with a VLCK diet is novel and potentially clinically significant but requires further validation. These data provide additional support for the concept of metabolic advantage with diets representing extremes in macronutrient distribution.     

Obesity and sarcopenia after menopause are reversed by sex hormone replacement therapy

OBJECTIVE: Menopause is linked to an increase in fat mass and a decrease in lean mass exceeding age-related changes, possibly related to reduced output of ovarian steroids. In this study we examined the effect of combined postmenopausal hormone replacement therapy (HRT) on the total and regional distribution of fat and lean body mass. RESEARCH METHODS AND PROCEDURES: Sixteen healthy postmenopausal women (age: 55 +/- 3 years) were studied in a placebo-controlled, crossover study and were randomized to 17beta estradiol plus cyclic norethisterone acetate (HRT) or placebo in two 12-week periods separated by a 3-month washout. Total and regional body composition was measured by DXA at baseline and in the 10th treatment week in both periods. Changes were compared by a paired Student's t test. RESULTS: The change in body weight during HRT was equal to the change during placebo (-24.6 g vs. -164 g, p = 0.42), but relative fat mass was significantly reduced (-0.5% vs. +1.24%, p < 0.01). During HRT, compared with during placebo, lean body mass increased (+347 g vs. -996 g, p < 0.01) and total fat mass decreased (-400 g vs. +836 g, p = 0.06). Total bone mineral content increased (+28.9 g vs. -4.4 g, p = 0.04) and abdominal fat decreased (-185 g vs. +253 g, p = 0.04) during HRT compared with placebo. DISCUSSION: HRT is linked to the reversal of both menopause-related obesity and loss of lean mass, without overall change in body weight. The increase in lean body mass during HRT is likely explained by muscle anabolism, which in turn, prevents disease in the elderly.     

The effect of whey isolate and resistance training on strength, body composition, and plasma glutamine

Different dietary proteins affect whole body protein anabolism and accretion and therefore, have the potential to influence results obtained from resistance training. This study examined the effects of supplementation with two proteins, hydrolyzed whey isolate (WI) and casein (C), on strength, body composition, and plasma glutamine levels during a 10 wk, supervised resistance training program. In a double-blind protocol, 13 male, recreational bodybuilders supplemented their normal diet with either WI or C (1.5 gm/kg body wt/d) for the duration of the program. Strength was assessed by 1-RM in three exercises (barbell bench press, squat, and cable pull-down). Body composition was assessed by dual energy X-ray absorptiometry. Plasma glutamine levels were determined by the enzymatic method with spectrophotometric detection. All assessments occurred in the week before and the week following 10 wk of training. Plasma glutamine levels did not change in either supplement group following the intervention. The WI group achieved a significantly greater gain (P < 0.01) in lean mass than the C group (5.0 +/- 0.3 vs. 0.8 +/- 0.4 kg for WI and C, respectively) and a significant (P < 0.05) change in fat mass (-1.5 +/- 0.5 kg) compared to the C group (+0.2 +/- 0.3 kg). The WI group also achieved significantly greater (P < 0.05) improvements in strength compared to the C group in each assessment of strength. When the strength changes were expressed relative to body weight, the WI group still achieved significantly greater (P < 0.05) improvements in strength compared to the C group.     

Effects of birth cohort and age on body composition in a sample of community-based elderly

BACKGROUND: The effect of the recent obesity epidemic on body composition remains unknown. Furthermore, age-related changes in body composition are still unclear. OBJECTIVE: The objective was to simultaneously examine the effects of birth cohort and age on body composition. DESIGN: A total of 1786 well-functioning, community-based whites and blacks (52% women and 35% blacks) aged 70-79 y from the Health, Aging, and Body Composition Study underwent dual-energy X-ray absorptiometry annually from 1997 to 2003. RESULTS: At baseline, mean +/- SD percentage body fat, fat mass, and lean mass (bone-free) were 28 +/- 5%, 24 +/- 7 kg, and 56 +/- 7 kg, respectively, for men and 39 +/- 6%, 28 +/- 9 kg, and 40 +/- 6 kg for women. Mixed models were used to assess the effects of cohort and age-related changes on body composition. Later cohorts in men had a greater percentage body fat (0.32% per birth year, P < 0.0001) than did earlier cohorts. This cohort effect was due to a greater increase in fat mass than in lean mass (0.45 kg and 0.17 kg/birth year, respectively). With increasing age, percentage body fat in men initially increased and then leveled off. This age-related change was due to an accelerated decrease in lean mass and an initial increase and a later decrease in fat mass. Similar but less extreme effects of cohort and age were observed in women. CONCLUSIONS: The combination of effects of both birth cohort and age leads to bigger body size and less lean mass in the elderly.     

Energy expenditure economy induced by decrease in lean body mass in anorexia nervosa

In anorexia nervosa, the low energy input associated with the classic overactivity during the malnourished state needs a sparing of energy expended at rest and also during physical activity. Therefore, we measured energy expenditure, both at rest and during moderate bicycling exercise (30W, 6 min), in 11 adult anorectic patients (weight 35.15 +/- 4.30 kg, mean +/- s.d.) at the beginning of their treatment and again after a mean weight gain of about 8.4 kg. During the malnourished state, the resting energy expenditure (REE) was lower than that predicted according to Harris and Benedict (P less than 0.001). Although it was significantly increased after weight gain (P less than 0.05), the REE per kg of lean body mass remained unchanged after repletion. The total oxygen consumption related to exercise remained unchanged after refeeding (2114 +/- 487 ml/15 min, basal vs 2168 +/- 394 ml/15 min, repletion) (n.s.). Thus in anorexia nervosa, weight loss and malnutrition did not induce economy either in energy expended at rest per unit of lean body mass nor in the energy expended in moderate cycling activity.     

Resting metabolic rate of esophageal carcinoma patients: a model for energy expenditure measurement in a homogenous cancer population

In cancer patients controversy exists as to the nature of changes in resting metabolic rate (RMR) and their contribution to cachexia. This study describes the fasting indirect calorimetry, and nutritional measurements made on a homogeneous group of Black patients with carcinoma of the esophagus. It compares them with a reference group. All cancer patients had localized disease and were markedly malnourished. They were on average 20 to 25% lighter than reference subjects. In the cancer patients, the triceps skinfold thickness (TSF) in mm and the hand grip strength in kg/m2, mean and SD, were, respectively, 7.3 +/- 2.8 and 28 +/- 6 for men and 12 +/- 5 and 22 +/- 3.5 for women, and were significantly lower than those of the reference subjects. Fat-free mass was calculated from the TSF measurements. In men with cancer RMR (6.06 MJ/day +/- 0.56) was significantly lower than the reference subjects values (7.07 MJ/day +/- 0.64) p = 0.002. In women with cancer RMR was on average 2 MJ/day less than in controls but this difference failed to reach significance. However, when expressed per kg fat free mass, or per kg body weight this difference is no longer apparent the RMR being 0.14 MJ/kg/fat free mass in both groups. Our interpretation is that there is no direct effect of the tumour on RMR and that energy expenditure changes are secondary to body composition changes.     

Changes of body fat mass determined by be-electrical impedance and by anthropometry: BMI method and skinfolds method in overweight and obese women after implementation of low energy diet

OBJECTIVE: To estimate the effect of a low energy diet on body fat mass measured by bioelectrical impedance (BIA) in overweight (BMI > or = 25 < 30) and obese women (BMI > or = 30). DESIGN: Randomised six weeks trial. METHODS: The studied group consisted of 86 women aged 20-67 attended the Outpatients Clinic of Metabolic Disorders. Dietary assessments were performed by 24-hour dietary recall. Body fat mass was measured by bioelectrical impedance method and by skinfolds thickness method. Percent body fat and fat free mass was estimated from equations based on BMI and skinfolds thickness. RESULTS: In overweight women after 6 weeks of dietary treatment mean intake of energy decreased from 10071 +/- 2678 kJ to 4560.6 +/- 1405.8 kJ, total fat intake from 88.7 +/- 33.9 g/d (33.4% of energy) to 38.8 +/- 19.9 g/d (31.1% of energy), protein intake from 89.5 +/- 36.5 g/d (14.8% of energy) to 50.7 +/- 16.9 g/d (19.0% of energy), carbohydrates intake from 312.7 +/- 106.6 g/d (51.8% of energy) to 134.5 +/- 53.7 g/d (50% of energy). In obese women mean intake of energy decreased from 10,376.3 +/- 2953.9 kJ to 4665.2 +/- 1380.7 kJ. The value of total energy, total fat and saturated fatty acids intake correlated with body weight, BMI and body fat. After dietary treatment the body weight decreased by 2.4 kg (3.3%) in overweight women and by 3.9 kg (4.1%) in obese women and percent of body fat decreased by 1.6% and 2.3%, respectively. Body fat mass determined by BIA method significantly correlated with skinfolds method by Siri, Schutte, Rathbun, Brozek, Keys-Brozek, and BMI method by Webster, Deurenberg. CONCLUSION: BIA method may be a helpful tool for the analysis of changes in total body composition occurring under obesity treatment.     

Increasing fluid milk favorably affects bone mineral density responses to resistance training in adolescent boys

This study examined the effects of increasing milk on bone and body composition responses to resistance training in adolescents. Twenty-eight boys (13 to 17 years of age) were randomly assigned to consume, in addition to their habitual diet, 3 servings/day of 1% fluid milk (n=14) or juice not fortified with calcium (n=14) while engaged in a 12-week resistance-training program. For all subjects combined, there were significant (P相似文献   

Validation of dual x-ray absorptiometry for body-composition assessment of rats exposed to dietary stressors.

Evidence of the validity and accuracy of dual x-ray absorptiometry (DXA) to measure soft-tissue composition of laboratory rats with altered body composition associated with nutritional perturbations is lacking. We compared DXA determinations made in prone and supine positions with measurements of chemical composition of 49 male, weanling Sprague-Dawley rats that were fed the basal AIN-93 growth diet, were fed the basal diet modified to contain 30% fat, were fasted for 2 d, were limit fed 6 g of the basal diet daily for 1 wk, or were treated with furosemide (10 mg/kg intraperitoneally 2 h before DXA). DXA produced similar estimates of body mass and soft-tissue composition in the prone and supine positions. DXA estimates of body composition were significantly correlated with reference composition values (R(2) = 0.371-0.999). DXA discriminated treatment effects on body mass, fat-free and bone-free mass, fat mass, and body fatness; it significantly underestimated body mass (1% to 2%) and fat-free and bone-free mass (3%) and significantly overestimated fat mass and body fatness (3% to 25%). The greatest errors occurred in treatment groups in which body mass was diminished and body hydration was decreased. These findings suggest that DXA can determine small changes in fat-free, bone-free mass in response to obesity and weight loss. Errors in DXA determination of fat mass and body fatness associated with extra corporeal fluid and dehydration indicate the need for revision of calculation algorithms for soft-tissue determination.     

Pre- and post-season dietary intake, body composition, and performance indices of NCAA division I female soccer players

Little published data describe the dietary and physiological profiles of intercollegiate female soccer players; therefore, the purpose of this investigation was to report baseline dietary data, anthropometrics, and performance indices of soccer women during rigorous pre-season training (2 sessions/day) and then during the post-competitive season. Members of a NCAA Division I women's soccer squad completed 3-day diet records, anthropometrics, and physical tests, including VO2peak. Average body mass was 62 kg with 16% body fat, and no significant pre to post differences were observed. Total energy, carbohydrate (CHO), protein, and fat intakes were significantly greater during the pre-season. Pre-season energy intake met the DRI for females with an "active" lifestyle (37 kcal/kg). While CHO intake failed to meet minimum recommendations to promote glycogen repletion (7-10 g/kg), protein and fat intakes were above minimum recommendations. Pre- and post-season intakes of several micronutrients were marginal (<75% of the DRI) including vitamin E, folate, copper, and magnesium. VO2peak significantly improved from pre- to post-season (42 and 50 ml/kg/min). In this study female soccer players appeared to meet caloric needs during periods of training but failed to meet minimum CHO and micronutrient recommendations. Foods higher in protein and fat displaced more CHO-rich and nutrient-dense foods within athletes' energy requirements and satiety limits.     

A comparison of air displacement plethysmography with three other techniques to determine body fat in healthy adults.

BACKGROUND: This study compared air displacement plethysmography (ADP), which relies on measurements of body density to estimate body fat, with three other techniques that measure body composition: (1) hydrostatic weighing (HW), which also measures body density; (2) bioelectrical impedance (BIA), which determines electrical resistance and total body water to estimate fat-free mass; and (3) dual-energy x-ray absorptiometry (DXA), which measures bone, fat, and fat-free soft tissue masses. METHODS: ADP, HW, BIA, and DXA were performed on 20 healthy volunteers (10 males and 10 females). The subjects were within 20% of ideal body weight, 31.1 +/- 1.8 years of age, and 75.4 +/- 2.7 kg with body mass index values of 25.2 +/- 0.9 (kg/m2) and percent body fat by ADP ranging from 6.0% to 41.0%. RESULTS: Percent body fat measurements by the four methods were highly correlated (r > .90, p < .0001). Mean body fat as determined by ADP, HW, BIA, and DXA were 23.4% +/- 2.3%, 23.9% +/-1.8%, 23.1% +/- 1.9%, and 26.4% +/- 2.4%, respectively (* p < .05 vs ADP). There was a significantly positive slope (+0.23) for the individual differences vs the average of ADP and HW percent body fat, demonstrating a slightly negative difference at lower body fat levels and a slightly positive difference at greater body fat levels. Although the average percent body fat determined by ADP was similar to that by HW for the entire population, there was a significant gender difference with the average body fat measured by ADP being 16% less in males and 7% greater in females than that determined by HW. CONCLUSIONS: Body fat measurements using ADP were highly correlated with those using HW, BIA, and DXA across a relatively wide range of body fat levels in healthy adults. These results support the utility of ADP as a relatively new technique in the estimation of percent body fat in healthy adults. However, the error associated with gender and the level of body fat is not negligible and requires further investigation.     

Body fatness, physical activity, and nutritional behaviours in Asian Indian immigrants to New Zealand

Body fatness, physical activity, and nutritional behaviours were assessed in 112 (50 male, 62 female) Asian Indians living in New Zealand. Participants were aged 44-91 years (mean 67.5 +/- 7.6) and had lived in New Zealand on average 51 months. Height, weight, and waist circumference were measured to determine body mass index (BMI) and central adiposity. Bioelectrical impedance was used to derive fat free mass, fat mass, and percentage body fat. Pedometers were worn to record daily steps taken over each of seven consecutive days. A lifestyle and health questionnaire was administered to collect information on nutrition behaviours. Average BMI for the sample was 27.2 +/- 4.7 kg/m2 with females (28.0 +/- 5.4 kg/m2) significantly higher than males (25.6 +/- 5.4 kg/m2). Using Asian Indian specific cut-offs 69% of the sample was obese (BMI>=25 kg/m2) and a further 13.7% overweight (23>=BMI<25 kg/m2). Average percentage body fat for the sample was 41.1 +/- 9.1 with females significantly higher than males. The majority (74%) reported some form of chronic condition, with 35% diagnosed with diabetes. Physical activity levels for the sample were low (5,977 +/- 3,560 steps/day) and significantly different between males (6,982 +/- 4,426) and females (5,159 +/- 2,401). Higher pedometer steps were associated with lower waist circumference. After adjustment for age, physical activity was lower, but nutritional habits better for those who had spent a longer time in New Zealand. In summary, Asian Indian immigrants to New Zealand have low physical activity levels and high levels of overweight/obesity and lifestyle disease.     

Body composition in adolescents with anorexia nervosa.

BACKGROUND: Malnourished patients with anorexia nervosa have altered body composition characterized by depletion of fat and fat-free mass. OBJECTIVES: The objectives of this study were to assess the body composition of adolescents with anorexia nervosa compared with that of control subjects and to investigate the relation between simple anthropometric measures and reference techniques for measuring body composition. DESIGN: Twenty-three adolescent females with anorexia nervosa aged 15.46 +/- 1.34 y (x +/- SD) were studied. Body composition was measured by anthropometry, dual-energy X-ray absorptiometry (DXA) (for body fat), and prompt gamma in vivo neutron activation analysis [for total body nitrogen (TBN)]. Twenty-five female subjects provided the control DXA data. TBN measurements were compared with prediction equations based on sex, height, age, and weight. RESULTS: Anorexia nervosa patients had significantly lower weight (40.2 +/- 4.6 kg), body mass index (in kg/m(2): 15.3 +/- 1.2), percentage of body fat (DXA) (13.8 +/- 5.8%), percentage of TBN predicted for age (73 +/- 10%), trunk fat (2.1 +/- 1.0 kg), leg fat (2.6 +/- 1.1 kg), and trunk-to-leg fat ratio than did control subjects (P < 0.05). In anorexia nervosa patients, significant correlations were found between triceps skinfold thickness and percentage of body fat (r = 0.83), body mass index and percentage of body fat (r = 0.46), and body weight and TBN (r = 0.84, P < 0.05). CONCLUSIONS: Hospitalized adolescent females with anorexia nervosa are depleted of total body fat and protein. We identified 3 simple anthropometric measures (triceps skinfold thickness, BMI, and body weight) that can be used to assess body composition and nutritional status in malnourished adolescents with anorexia nervosa.     

Effect of rosiglitazone on insulin sensitivity and body composition in type 2 diabetic patients [corrected

OBJECTIVE: To investigate the effects of rosiglitazone (RSG) on insulin sensitivity and regional adiposity (including intrahepatic fat) in patients with type 2 diabetes. RESEARCH METHODS AND PROCEDURES: We examined the effect of RSG (8 mg/day, 2 divided doses) compared with placebo on insulin sensitivity and body composition in 33 type 2 diabetic patients. Measurements of insulin sensitivity (euglycemic hyperinsulinemic clamp), body fat (abdominal magnetic resonance imaging and DXA), and liver fat (magnetic resonance spectroscopy) were taken at baseline and repeated after 16 weeks of treatment. RESULTS: There was a significant improvement in glycemic control (glycosylated hemoglobin -0.7 +/- 0.7%, p < or = 0.05) and an 86% increase in insulin sensitivity in the RSG group (glucose-disposal rate change from baseline: 17.5 +/- 14.5 micro mol glucose/min/kg free fat mass, p < 0.05), but no significant change in the placebo group compared with baseline. Total body weight and fat mass increased (p < or = 0.05) with RSG (2.1 +/- 2.0 kg and 1.4 +/- 1.6 kg, respectively) with 95% of the increase in adiposity occurring in nonabdominal regions. In the abdominal region, RSG increased subcutaneous fat area by 8% (25.0 +/- 28.7 cm(2), p = 0.02), did not alter intra-abdominal fat area, and reduced intrahepatic fat levels by 45% (-6.7 +/- 9.7%, concentration relative to water). DISCUSSION: Our data indicate that RSG greatly improves insulin sensitivity in patients with type 2 diabetes and is associated with an increase in adiposity in subcutaneous but not visceral body regions.