Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BODY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32Linked to original sources
PubMed2005

Relationship of serum leptin with age, body weight, body mass index, and bone mineral density in healthy mainland Chinese women.

BACKGROUND: Serum leptin concentration is associated with age, fat and bone mineral density (BMD), and there are ethnic differences in physique and BMD values. The relationship between serum leptin concentration and BMD in Chinese women is presently unknown. We examined the relationship of serum leptin concentration with age, body weight, BMI and BMD in mainland Chinese women. METHODS: Serum leptin concentration in a population of 676 Chinese females, aged 20-80 years (45.4+/-14.8 years, mean+/-S.D.), was measured using an enzyme-linked immunosorbent assay (ELISA). BMD values were measured by dual-energy X-ray absorptiometry (DXA) at a number of sites: the posteroanterior lumbar spine (PA, L1-L4), lateral lumbar spine (Lat, L2-L4), hip (including the femoral neck (FN) and total hip (T-hip)), and forearm (one-third region (RU1/3) and total region (RUT)). The relationship between changes in serum leptin concentration with age, body weight, height, body mass index (BMI) and BMD values at six sites were analyzed using 10 different regression models, and the models giving the best fit were selected. RESULTS: The cubic regression model best described the changes in serum leptin concentration with age (R(2)=0.048, p<0.001) and body weight (R(2)=0.352, p<0.001), while the quadratic regression model was best for serum leptin concentration changes with BMI (R(2)=0.410, p<0.001); serum leptin concentration was not correlated with height. Serum leptin concentration was significantly higher in postmenopausal than premenopausal women (p<0.001). Serum leptin concentration was correlated with Lat BMD (R(2)=0.012, p<0.018), FN BMD (R(2)=0.006, p<0.041) and T-hip BMD (R(2)=0.013, p<0.004) in the whole population. In premenopausal women, leptin was positively associated with BMD except for Lat (R(2)=0.029-0.055, p<0.008); in postmenopausal women, leptin was also positively associated with AP, FN, T-hip BMD (R(2)=0.026-0.042, p<0.007). However, after adjusting for BMI not for body weight, there was no association between serum leptin concentration and age. Meanwhile, after adjustment for age, body weight and BMI, there was no association between serum leptin concentration and BMD values in premenopausal and postmenopausal women. CONCLUSIONS: Age-related changes in serum leptin concentration is dependent on BMI, but not a direct determinant of BMD in Chinese females.

Absorptiometry, Photon↗
PubMed2006

Body size, body proportions, and mobility in the Tyrolean "Iceman".

Body mass and structural properties of the femoral and tibial midshafts of the "Iceman," a late Neolithic (5,200 BP) mummy found in the Tyrolean Alps, are determined from computed tomographic scans of his body, and compared with those of a sample of 139 males spanning the European early Upper Paleolithic through the Bronze Age. Two methods, based on femoral head breadth and estimated stature/bi-iliac (pelvic) breath, yield identical body-mass estimates of 61 kg for the Iceman. In combination with his estimated stature of 158 cm, this indicates a short but relatively wide or stocky body compared to our total sample. His femur is about average in strength compared to our late Neolithic (Eneolithic) males, but his tibia is well above average. His femur also shows adaptations for his relatively broad body (mediolateral strengthening), while his tibia shows adaptations for high mobility over rough terrain (anteroposterior strengthening). In many respects, his tibia more closely resembles those of European Mesolithic rather than Neolithic males, which may reflect a more mobile lifestyle than was characteristic of most Neolithic males, perhaps related to a pastoral subsistence strategy. There are indications that mobility in general declined between the European Mesolithic and late Neolithic, and that body size and shape may have become more variable throughout the continent following the Upper Paleolithic.

Adult↗
PubMed2005

Aerobic exercise training improves insulin sensitivity without changes in body weight, body fat, adiponectin, and inflammatory markers in overweight and obese girls.

The aim of this study was to examine the effect of aerobic exercise training on insulin sensitivity in overweight and obese girls. Nineteen overweight and obese girls (mean +/- SD: age, 13.1+/-1.8 years; body mass index, 26.8+/-3.9 kg/m(2)) volunteered for this study. Body composition (dual-energy x-ray absorptiometry), insulin sensitivity (oral glucose tolerance test and homeostasis model assessment estimate of insulin resistance; n=15), adiponectin, C-reactive protein (CRP), interleukin (IL) 6, insulin-like growth factor-1, soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 serum levels, and blood lipids and lipoproteins were assessed before and after 12 weeks of aerobic training. Cardiorespiratory fitness increased by 18.8% (P<.05) as a result of training. The area under the insulin concentration curve (insulin area under the curve) decreased by 23.3% (12781.7+/-7454.2 vs 9799.0+/-4918.6 microU.min/mL before and after intervention, respectively; P=.03). Insulin sensitivity was improved without changes in body weight (pre-intervention, 67.9+/-14.5 kg; post-intervention, 68.3+/-14.0 kg) or percent body fat (pre-intervention, 41.4% +/- 4.8%; post-intervention, 40.7%+/-5.2%). The lower limb fat-free mass increased by 6.2% (P<.01) as a result of training, and changes in lower limb fat-free mass were correlated with changes in the insulin area under the curve (r= -.68; P< .01). Serum adiponectin, IL-6, and CRP concentrations did not change (pre-intervention vs post-intervention: adiponectin, 9.57+/-3.01 vs 9.08+/-2.32 microg/mL; IL-6, 1.67+/-1.29 vs 1.65+/-1.25 pg/mL, CRP, 3.21+/-2.48 vs 2.73+/-1.88 mg/L) whereas insulin-like growth factor-1 was lower after training (pre-intervention, 453.8 +/- 159.3 ng/mL; post-intervention, 403.2+/- 155.1 ng/mL; P<.05). In conclusion, 12 weeks of aerobic training improved insulin sensitivity in overweight and obese girls without change in body weight, percent body fat, and circulating concentrations of adiponectin, IL-6, CRP, and other inflammatory markers. These findings suggest that increased physical activity may ameliorate the metabolic abnormalities associated with obesity in children with a mechanism other than the parameters cited earlier.

Adiponectin↗
PubMed2002

Preconscious processing of body image cues. Impact on body percept and concept.

OBJECTIVE: There is considerable evidence that body image is an elastic construct, which can be influenced by environmental and internal factors. The present study used a visual subliminal processing paradigm, with the aim of determining the impact of preconscious processing of verbal cues upon body image (percept and concept). METHOD: Forty nonclinical women completed measures of body percept and concept before and after being exposed to very rapid presentations (4 ms) of fatness and thinness cues. RESULTS: The women with relatively unhealthy eating attitudes were influenced by the fatness stimulus, with a worsening of their body percept and concept. In contrast, the women with healthier eating attitudes showed an improvement in their body percept in response to the thinness stimulus. CONCLUSION: The findings support the centrality of body image schemata in eating psychopathology, although there is a need for replication and extension in other groups.

Adult↗
PubMed1999

Plasma plasminogen activator inhibitor-I is associated with plasma leptin irrespective of body mass index, body fat mass, and plasma insulin and metabolic parameters in premenopausal women.

Leptin, the satiety hormone expressed almost exclusively in adipose tissue, is a marker of body fat accumulation in humans. Recent studies have shown that plasminogen activator inhibitor-1 (PAI-1), a prothrombotic factor associated with atherosclerosis complications, is also produced in adipose tissue. The objective of the present study was to determine whether PAI-1 antigen plasma concentrations are associated with leptin plasma levels or the body fat mass (FM) independently of the variables known to influence PAI-1 production. Sixty-one nondiabetic women aged 18 to 45 years with a wide range of values for the body mass index ([BMI] 18.1 to 37.7 kg/m2) were evaluated for (1) body FM and fasting plasma levels of (2) PAI-1 antigen, (3) PAI-1 activity, (4) leptin, (5) insulin, (6) blood glucose, and (7) lipids (cholesterol, high-density lipoprotein [HDL]-cholesterol, and triglycerides [TG]). Body FM and fat-free mass (FFM) were estimated during fasting conditions by the bioimpedance analysis (BIA) method using a tetrapolar device. Body fat distribution was evaluated by the waist circumference and the waist to hip ratio (WHR). FM was directly associated with both PAI-1 antigen (r = .585, P < .001) and PAI-1 activity (r = .339, P < .001). Seemingly, leptin was positively related to both PAI-1 antigen (r = .630, P < .001) and PAI-1 activity (r = .497, P < .001). Moreover, both PAI-I antigen and PAI-1 activity were directly correlated with FFM (r = .285, P < .05, and r = .336, P < .01, respectively), BMI (r = .594, P < .001, and r = .458, P < .001, respectively), and WHR (r = .510, P < .001, and r = .391, P < .005, respectively). Insulin was directly related to PAI-1 antigen (r = .540, P < .001), PAI-1 activity (r = .259, P < .05), leptin (r = .447, P < .001), and FM (r = .435, P < .001). The association between PAI-1 antigen (dependent variable) and leptin or FM was tested by a stepwise regression model simultaneously including leptin, FM, BMI, WHR, age, FFM, and fasting insulin, blood glucose, TG, cholesterol, and HDL-cholesterol as independent variables. PAI-1 antigen maintained a significant positive independent relationship only with leptin (t = 2.923, P < .01), insulin (t = 3.489, P < .001), and fasting blood glucose (t = 2.092, P < .05), and a negative independent relationship with HDL-cholesterol (t = -2.634, P < .05). In conclusion, the strong relationship between PAI-1 antigen and leptin irrespective of other variables known to influence these factors seems to indicate that leptin per se may potentially increase PAI-1 plasma concentrations in obese subjects.

Adipose Tissue↗
PubMedDate not supplied

Body composition interpretation. Contributions of the fat-free mass index and the body fat mass index.

OBJECTIVE: Low and high body mass index (BMI) values have been shown to increase health risks and mortality and result in variations in fat-free mass (FFM) and body fat mass (BF). Currently, there are no published ranges for a fat-free mass index (FFMI; kg/m(2)), a body fat mass index (BFMI; kg/m(2)), and percentage of body fat (%BF). The purpose of this population study was to determine predicted FFMI and BFMI values in subjects with low, normal, overweight, and obese BMI. METHODS: FFM and BF were determined in 2986 healthy white men and 2649 white women, age 15 to 98 y, by a previously validated 50-kHz bioelectrical impedance analysis equation. FFMI, BFMI, and %BF were calculated. RESULTS: FFMI values were 16.7 to 19.8 kg/m(2) for men and 14.6 to 16.8 kg/m(2) for women within the normal BMI ranges. BFMI values were 1.8 to 5.2 kg/m(2) for men and 3.9 to 8.2 kg/m(2) for women within the normal BMI ranges. BFMI values were 8.3 and 11.8 kg/m(2) in men and women, respectively, for obese BMI (>30 kg/m(2)). Normal ranges for %BF were 13.4 to 21.7 and 24.6 to 33.2 for men and women, respectively. CONCLUSION: BMI alone cannot provide information about the respective contribution of FFM or fat mass to body weight. This study presents FFMI and BFMI values that correspond to low, normal, overweight, and obese BMIs. FFMI and BFMI provide information about body compartments, regardless of height.

Adipose Tissue↗
PubMed2001

Associations between body height, body composition and cholesterol levels in middle-aged men. the coronary risk factor study in southern Sweden (CRISS).

BACKGROUND: Short body height is associated with increased risk for coronary heart disease; however, mechanisms are not fully explained. In this study, associations between body height and serum cholesterol, non-high-density lipoprotein (non-HDL cholesterol) and high-density lipoprotein (HDL cholesterol) were investigated. METHODS: Prospective cohort study of middle-aged men from Helsingborg, Sweden starting 1990. Two birth-year cohorts were invited at 37, 40 and 43 years of age; participation at baseline was 991 (68%). Serum and HDL cholesterol, systolic and diastolic blood pressure, weight, height, waist and hip circumferences were measured. Non-HDL cholesterol, body mass index (BMI) and waist/ hip ratio (WHR) were calculated. The participants completed a questionnaire covering lifestyle variables. RESULTS: There were statistically significant inverse correlations between body height and serum cholesterol (-0.11) and non-HDL cholesterol (-0.12). One standard deviation, 6.7 cm, taller body height was associated with a lower serum cholesterol (-0.12 mmol/l) and a lower non-HDL cholesterol (-0.13 m mol/l; p < 0.001). These associations remained when adjusted for BMI and WHR. Men with serum cholesterol equal to or above 6.5 mmol/l were significantly shorter (mean 178.71 cm) than men with serum cholesterol below 6.5 mmol/l (mean 179.71 cm). In addition, BMI and WHR were positively associated with serum and non-HDL cholesterol and inversely associated with HDL cholesterol. The change in cholesterol levels over the six-year follow-up was significantly associated to the change in BMI and WHR. CONCLUSIONS: Body height had an independent and inverse relation to serum cholesterol and non-HDL cholesterol in middle-aged men, and the lipid pattern suggests that the underlying mechanism might be different from the traditional association between lipids and the metabolic syndrome. Although the direct clinical implication is limited, our results may help to explain the association between short height and risk of myocardial infarction.

Adult↗
PubMed2003

Body composition estimated by bioelectrical impedance in the Swedish elderly. Development of population-based prediction equation and reference values of fat-free mass and body fat for 70- and 75-y olds.

OBJECTIVE: To develop a bioelectrical impedance (BIA) prediction equation for fat-free mass (FFM(BIA)) and present reference values of FFM and body fat (BF) for healthy Swedish elderly from population-based representative samples. SUBJECTS: This study is based on 823 (344 males, 479 females) participants from two systematic samples of birth cohorts in Göteborg aged 70 (cohort H70V, 201 males and 299 females) and 75 (cohort NORA75, 143 males and 180 females). METHODS: Body composition was measured with BIA (BIA-101, RJL system, Detroit) in both cohorts and was estimated by a four-compartment (4C) model from total body water (TBW) and total body potassium (TBK) in a sub-sample of the NORA75 cohort. The FFM(BIA) was validated against the FFM from the 4C model (FFM(4C)). RESULTS: The FFM(BIA) correlated well with FFM(4C) (r=0.95, SEE=2.64 kg). The FFM(BIA) (kg) in 70-y-old males and females were 58.5+/-5.4 and 43.4+/-4.4, and for 75-y-old males and females were 56.1+/-4.7 and 42.5+/-4, respectively. The body fat in kg (FM) among 70-y-old males and females were 25.2+/-8.1 and 25.7+/-8.4, and for 75-y-old males and females were 21.7+/-7.1 and 22.8+7.2, respectively. The percent body fat (BF%) among 70-y-old males and females were 29.5+/-5.8 and 36.3+/-6.4, and for 75-y-old males and females were 27.3+/-6 and 34.1+/-6.1, respectively. CONCLUSION: The FFM, FM and BF% from this study might be used as reference values for Swedish elderly aged 70 and 75 y.

Adipose Tissue↗
PubMed1997

Effects of hydroxyurea administration on the body weight, body composition and exercise performance of patients with sickle-cell anaemia.

1. As an ancillary study carried out during the recently completed Multicenter Study of Hydroxyurea, we examined the effect of hydroxyurea on the body weight, body composition and exercise capacity of adult patients with sickle-cell anaemia. 2. The subjects received either hydroxyurea (six males and four females) or placebo (eight males and six females). Data for each subject were generated during four separate 24 h admissions to the General Clinical Research Center. These admissions occurred at baseline and then at 6, 12 and 18 months after the start of study drug (hydroxyurea or placebo) administration. During each admission, body composition was measured by using a dual X-ray absorptiometer, and exercise testing was performed by cycle ergometry. Anaerobic performance was assessed according to a 'Wingate' protocol (20 s at maximal intensity against a cycling resistance of 7.5% body weight). Aerobic performance was examined using a steady state submaximal exercise protocol (10 min cycling time). 3. At baseline, no significant difference in any parameter was found between the hydroxyurea- and placebo-treated groups. At 18 months, the hydroxyurea-treated subjects exhibited an average weight gain of 3.16 kg. The mean weight gain in the placebo-treated subjects was 1.82 kg. Body composition analysis showed that the additional weight in both groups involved both lean and fat body mass components. In anaerobic performance, the subjects given hydroxyurea showed an increase in peak muscle power of 104.9 W. The placebo group also showed an increase, but theirs was a more modest gain of 57.7 W. The most marked improvement in anaerobic performance was observed in the hydroxyurea-treated men (P < 0.05). In aerobic performance, the hydroxyurea-treated subjects exhibited a decrease in peak heart rate response to a standardized workload of 15.2 beats/min, as compared with a decrease of only 4.3 beats/min in the placebo-treated patients. 4. Taken together, the overall weight gain, combined with increases in both anaerobic muscular performance and aerobic cardiovascular efficiency, provides objective data to support the subjective impression that hydroxyurea administration produces an improvement in the physical capacity of patients with sickle-cell anaemia.

Adult↗
PubMed2001

Reducing body myopathy with cytoplasmic bodies and rigid spine syndrome: a mixed congenital myopathy.

At the age of five years a male child started to develop a progressive rigid spine, torsion scoliosis, and flexion contractures of his elbows, knees, hips, and ankles owing to severe proximal and distal muscle weakness. He had three muscle biopsies from three different muscles at ages 7, 11, and 14 years, respectively. Myopathologically, these muscle tissues contained numerous inclusions which, at the ultrastructural level, turned out to be reducing bodies and cytoplasmic bodies, often in close spatial proximity. Similar histological inclusions, although not further identified by histochemistry and electron microscopy, were seen in his maternal grandmother's biopsied muscle tissue who had developed weakness of the legs and hands after the age of 50 years. The patient's parents were healthy, but the mother's quadriceps muscle showed an increased spectrum of muscle fibre diameters. Our patient, thus, had a neuromuscular disorder, perhaps familial, presenting as a mixed congenital myopathy, i.e., reducing body myopathy with cytoplasmic bodies, of which the morphological lesions could be consistently documented over several years in his different limb muscles. While other mixed congenital myopathies had shown cores and rods, both related to sarcomeres and thus possibly morphogenetically related, cytoplasmic bodies thought to be related to Z-bands and reducing bodies dissimilar to any muscle fibre constituent do not share any common denominator. Therefore, we suggest that this neuromuscular disorder may be a unique mixed congenital myopathy, either sporadic or genetic. In the latter case, the transmission pattern suggested X-linked recessive inheritance, but an autosomal-dominant transmission with variable penetrance could not be ruled out.

Adult↗
PubMed2003

Effects of dietary protein concentration and specific amino acids on body weight, body composition and feather growth in young turkeys.

1. Two randomised block factorial experiments were conducted to investigate the relationships between the effects of dietary crude protein and specific amino acid concentrations on the relative growth of the body and feathers of young turkeys. 2. Decreasing dietary crude protein concentration from 300 to 180 g/kg in experiment 1 reduced the body and breast muscle weights of a large male line of turkeys proportionally by 0.44 and 0.52 compared with 0.19 and 0.24 in a small traditional line. 3. Decreasing dietary crude protein concentration was associated with a maximum reduction in feather weight of 0.18 and 0.24 respectively in male line and traditional turkeys. The length of the feathers in the cranial region of the breast decreased from 26 to 19mm in the traditional line compared with an increase from 14 to 25 mm in male line turkeys. 4. Decreasing dietary crude protein concentration was associated with an increase in the fat content of the feather-free carcase. Male line turkeys had a higher carcase fat and lower feather dry matter content than the traditional turkeys. 5. It was concluded that dietary crude protein was preferentially partitioned to feather rather than muscle growth in the male line in contrast to a traditional line of turkeys in which the growth of feathers and muscle were affected equally. 6. In experiment 2, the amino acids arginine, valine, methionine and tyrosine were added separately to a common basal ration (180g CP/kg) to raise their concentration to that of the control ration (260 g CP/kg). Each ration was fed ad libitum to male line turkeys from 2 to 6 weeks of age. 7. Amino acid supplementation increased body and breast muscle weights. 8. Compared with the basal ration, tyrosine was associated with a reduction in feather weight whereas valine had no effect. Supplementation with arginine and methionine resulted in increased feather weights that were similar to that of the controls. 9. It was concluded that arginine and methionine were used preferentially and are essential for feather growth. Excess amino acids that are not required for feather growth such as tyrosine and valine were used for increased body growth and resulted in relatively poor feather cover. 10. The results suggest that feather growth was maintained as much as possible at the expense of body growth when the amino acid concentration of the ration was less than that required to maximise body and muscle weight gain in large male line turkeys.

Amino Acids↗
PubMed1996

Heat production, body temperature, and body posture in west African dwarf goats infected with Trypanosoma vivax.

The relationships between heat production, body temperature, and body posture (standing/lying) were studied in goats suffering from trypanosomiasis. Sixteen goats were selected and infected with 1 x 10(6) Trypanosoma vivax parasites and 8 goats served as controls. In week 2, 4, and 6 after infection heat production, body posture, and body temperature were measured at 15-minute intervals. Heat production was higher (P < 0.01) in infected animals compared with control animals (342, respectively 306 kJ.kg- 0.75.d-1), body temperature was also higher (P < 0.001) in infected goats (39.78 degrees C, respectively 38.51 degrees C). The standing related energy costs per day were lower in infected animals (27 respectively 36 kJ.kg-0.75.d-1). Infected animals, therefore, masked part of the energy costs of infection by reducing the standing time. The heat production of infected animals was increased by 21 kJ.kg-0.75.d-1 per 1 degree C fever (7% increase). During periods of standing, body temperature increased with time, whereas during lying periods, it decreased. The number of standing periods was increased in infected animals. It was discussed whether postural behaviour is influenced by thermoregulatory mechanisms.

Africa South of the Sahara↗
PubMedDate not supplied

Variations in the assessment of the fat content of the human body due to experimental technique in measuring body density.

The body fat content of 15 adults, 6 females and 9 males, was estimated from body density. The body density of each individual was measured by weighing under water after (i) maximal expiration, (ii) moderate expiration, (iii) minimal expiration, (iv) moderate inspiration, (v) light meal, (vi) heavy meal, (vii) carbonated drink. Variations in the levels of expiration and inspiration caused only about 1% difference in the estimated fat content of the body. Consumption of food before the experiment had a similar effect. Comparatively large volumes of gas in the alimentary tract (caused by a carbonated drink before the experiment) resulted in a difference of about 1.5% in the body fat content. These variations observed in the estimation of body fat by densitometry are well within the basic errors of the method.

Adipose Tissue↗
PubMedDate not supplied

Body composition and body hydration in old age estimated by means of skinfold thickness and deuterium dilution.

In this study a group of 30 women and 30 men aged 60-90 years was examined. Body density was predicted from the sum of four skinfold thickness (SFT) as described by Durnin and Womersley (1974). Body composition, expressed as a percentage of total body weight as fat mass (FM) and fat free mass (FFM) was calculated by means of Siri's formula (Siri 1961). Total body water (TBW) was measured from the dilution of an oral deuterium dose and FFM calculated assuming a hydration of 73.2%. The FM% predicted from SFT showed a slight but not significant decreasing age trend from 28.3% to 25.4% in men, and from 40.3% to 37.8% in women. Body hydration (about 50% of body weight in men and 44% in women) remained constant throughout the age range. FFM obtained from TBW assuming a constant hydration of FFM, was found to be unchanged with age. FM% predicted from SFT was correlated with values obtained from TBW on an individual basis (R2 = 0.38; p less than 0.0001 in men and R2 = 0.31; p less than 0.002 in women), but the scatter was large. The Bland and Altman statistical analysis (Bland and Altman 1986) suggests that the discrepancy between the two estimates tends to be significantly more positive with increasing fatness of the subject. The assumption of a constant hydration of FFM between individuals and with advancing age was tested. The hydration of FFM was calculated as the ratio between TBW (from deuterium dilution) and FFM (estimated from SFT). The wide range of values (50% to 90%) suggests large inter-individual differences. The mean values were lower than commonly reported, and differed with age and sex. In men, FFM hydration steadily decreases with age from the 7th decade (70.2 +/- 7.7%) to the 10th decade (65.9 +/- 8.2%). Women showed higher average figures than those of men and a lower age-associated decline (72.5% and 68.5% respectively). Our results suggest that FFM hydration decreases with age, and this indicates the need to develop age-related correction factors in order to derive FFM from TBW in an elderly population.

Aged↗
PubMed1995

Comparison of body composition measured by total body potassium and infrared interactance.

OBJECTIVE: The purpose of this study was to find how closely a near infrared instrument (IRI), Futrex 5000, would compare to whole body counting (WBC) of potassium-40 (40K) in assessing body composition. DESIGN: We measured lean body mass (LBM) and percent total body fat (PCF) in 177 males and 27 females by total body potassium (TBK) and by infrared interactance (IRI). TBK was assessed by 2 pi whole body counter (WBC) and IRI by Futrex (F) instrument. These subjects were measured for TBK and for IRI within 1 week of each other. RESULT: A large mean difference (p < or = 0.001) was found between the results using the two instruments: IRI data for LBM were higher and PCF lower compared to TBK. CONCLUSION: As shown by repeated TBK measurements over a 22-year period in these same volunteers, this technique is reliable. The IRI assessments did not come to a close fit with TBK.

Adult↗
PubMed1999

Anthropometry, body composition and body image in dieting and non-dieting 8-16-year-old Swedish girls.

Anthropometry, body composition and body image were studied in 122 Swedish 8-16-y-old girls and their parents. The subjects participated in a 3-y prospective longitudinal study and were selected randomly after stratification for grades from those scoring in the upper vs. the lower thirds of the Children's Eating Attitudes Test (ChEAT) score distribution. The ChEAT was completed 6 mo before the present study together with a demographic and dieting questionnaire and a questionnaire for the estimation of body size. In total 43% (n = 52) admitted ever dieting ("Dieters") and 25% (n = 30) admitted that they were currently trying to lose weight. The anthropometric and body composition data indicated that ChEAT High-scorers and Dieters were somewhat fatter than Low-scorers and Non-dieters, although this pattern was not shown among the 8-y-olds or the 14-y-olds (High-scorers). The mothers of the ChEAT High-scorers were found to be somewhat fatter than the other mothers. A current vs. ideal body shape discrepancy was shown for both High-scorers and Dieters, with a larger discrepancy for the Dieters. All groups believed that their parents were aspiring for a leaner body.

Adolescent↗
PubMed2005

Patterns of bioelectrical impedance vector distribution by body mass index and age: implications for body-composition analysis.

BACKGROUND: Bioelectrical impedance analysis (BIA) gives resistance (R) and reactance (Xc). R and Xc normalized for body height (H) can be plotted as a bivariate vector (H(2)/Xc versus H(2)/R). Vector BIA is useful for studying the determinants of BIA results. OBJECTIVE: We investigated the effect of age on BIA results and its relevance to body-composition analysis in a large database of impedance vector distributions stratified by age, sex, and body mass index (BMI). DESIGN: Mean bivariate vector distribution patterns (95% confidence ellipses) were examined in a German population of 15605 children and adolescents and 213294 adults. Children and adolescents were divided into 3 age groups with up to 5 BMI categories. In adults, 5 BMI categories were stratified into 7 age groups. RESULTS: Mean impedance vectors were shorter in children than in adults. The vector distribution pattern was influenced by sex, BMI, and age, with shorter vectors in females than in males and longer vectors with increasing BMI. Consistent with a decrease in body cell mass with increasing age, there was a downward slope in the mean vector with age as a result of a decrease in the H(2)/Xc vector component. By contrast, there was no age-dependent increase in the H(2)/R vector component. In women of the same BMI at different ages, H(2)/R and percentage fat mass tended to decrease with age. CONCLUSIONS: The lack of an age-dependent increase in the H(2)/R vector component renders conventional BIA unsuitable for an examination of the age-related increase in body fat mass. By contrast, the increase in the H(2)/Xc vector component with advancing age suggests the potential of BIA to depict the age-related decrease in body cell mass.

Adolescent↗
PubMed1979

A review of body composition studies with emphasis on total body water and fat.

Tritiated water meausres a volume 4 to 15% body weight larger than that by desiccation, and, at present, only 0.5 to 2.0% of the overestimation can be explained by the exchange of hydrogen of tritiated water with those of the proteins and carbohydrates of the body. The remainder of the error is unexplained. Water in the lumen of the gut is an appreciable percentage of total body water (TBW) in many mammalian species, with the pig and the human as possible exceptions, and it should be considered an integral part of TBW. Consequently, the exclusion or inclusion of this transcellular water as part of TBW significantly affects the final TBW volume. As tritiated water exchanges with water in the gut, a comparison of the data from the indirect method with the data from the direct method can only be made when water in the gut is included in the desiccation method. Conceptually, the amount of water in lean body mass is a reflection of the actively metabolizing cell mass of the body. However, water in the gut is outside this cell mass, and if included, it significantly overestimates the water associated with the lean body mass compartment. The percentage of water in fat-free wet weight for most mature animals is estimated at 73.2%, although the mean values in the literature range from 63% for the beagle to 80% for the mouse, with the mean for the majority of species between 70 and 76%. If the percentage of water in fat-free wet weight lies between 70 and 76% for most species, then the error in calculating fat using the figure 73.2% in the equation (% fat = 100 - % TBW/0.732) is significant. In the application of this equation, the largest potential error lies in the estimation of TBW with tritiated water.

Adipose Tissue↗