PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Body Composition”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 757 records · Page 42Linked to original sources

Growth hormone, body composition and somatomedin C after treatment of acromegaly.

Acromegaly is associated with abnormal indices of body composition (as determined by exchangeable sodium, exchangeable potassium and total body water estimations) which may be corrected by treatment. We related these indices of body composition to the attained growth hormone levels (mean of five daytime values) in 42 treated acromegalics. Somatomedin C was measured in 30 subjects. The mean duration of treatment was 7.7 years (range 1-26). Exchangeable sodium, potassium and total body water were significantly lowered by treatment. After treatment of acromegaly subjects whose growth hormone level was below 5 mU/l achieved normal body composition more often than those with higher levels. Growth hormone concentration of below 5 mU/l after treatment should be regarded as more appropriate index of control of acromegaly than the higher levels previously recommended.

Acromegaly↗

Changes in weight and body composition after orthognathic surgery and jaw fractures: a comparison of miniplates and intermaxillary fixation.

OBJECTIVES: To compare the changes in postoperative weight and body composition following orthognathic surgery or jaw fractures treated by intermaxillary fixation (IMF) or miniplate osteosynthesis. DESIGN: A 4-month non-randomised prospective pilot study. Body composition was assessed using the 4 site skinfold thickness technique. The fixation method used in each case was dependent on clinical criteria alone. SETTING: Oral and maxillofacial surgery units at St James's University Hospital and the General Infirmary at Leeds. SUBJECTS: All patients were eligible for inclusion in the study if they had sustained a jaw fracture or had undergone orthognathic surgery. Patients were excluded if they had sustained polytrauma, if their sole orthognathic surgery procedure was a genioplasty and if the author was not directly involved in their management. The final study group consisted of 22 patients, 18 following surgical correction of jaw fractures and 4 following elective orthognathic surgery. Thirteen patients were managed with intermaxillary fixation and 9 patients were treated with miniplate osteosynthesis. MAIN OUTCOME MEASURES: Weight, lean body mass, total body water, fat and water free lean body mass, 1 week and 6 weeks postoperatively. RESULTS: There was no significant difference in weight loss or body composition changes between the plated and non plated groups at 1 week postoperatively. However, by 6 weeks postoperatively the IMF group had lost significantly more weight (4.5 kg) than the plated group (1.1 kg). In the plated group this weight loss resulted entirely from a loss of lean body mass (77% water), whereas in the other group it resulted from a fat loss of 1.2 kg plus a lean body mass loss of 3.3 kg (73% water). Estimated protein losses were 0.9 kg for the IMF group and 0.3 kg for the plated group. CONCLUSIONS: Intermaxillary fixation compromises nutritional status in the early postoperative period leading to loss of water, fat and protein. The results of this pilot study suggest that further investigation of postoperative weight and body composition changes after oral and maxillofacial operations is indicated.

Adipose Tissue↗

Bioelectrical impedance analysis for the estimation of body composition in rats.

Bioelectrical impedance analysis (BIA) was used to assess body composition in rats fed on either standard laboratory diet or on high-fat diet designed to induce obesity. Bioelectrical impedance analysis predictions of total body water and thus fat-free mass (FFM) for the group mean values were generally within 5% of the measured values by tritiated water (3H2O) dilution. The limits of agreement for the procedure were, however, large, approximately +/- 25%, limiting the applicability of the technique for measurement of body composition in individual animals.

Adipocytes↗

Relationships among body composition, hemorheology and exercise performance in rugbymen.

We investigated relationships among body composition, blood rheology, and exercise performance in 14 rugbymen (19-31 yr, weight 65.8-109.2 kg, height 1.7-1.96 m, body mass index 21.7-33.1 kg/m2) who underwent a standardized submaximal exercise session on cycloergometer corresponding to 225 kJ over 30 min. The rheologic response to exercise was measured with the MT90 viscometer and the Myrenne aggregometer. Dehydration, evaluated by precision weighing, resulted in a loss of 360 to 973 g water, i.e., 1.69 to 4.32 g/kJ. This loss of water is not correlated to plasma volume contraction as assessed by the equation of Greenleaf. Hemorheologic changes are observed, but they are correlated neither to water loss, nor to plasma volume contraction. A 36% increase in blood viscosity (p < 0.01) is mainly explained by a red blood cell rigidification (p < 0.02), although hematocrit and plasma viscosity also increase (p < 0.01). Isometric adductor strength (specific ergometer) is correlated to erythrocyte flexibility (r = 0.680, p < 0.01). Red cell aggregability (Myrenne aggregometer) is correlated to fat mass measured by bioelectrical impedance (r = 0.634, p < 0.02). Aerobic working capacity index W170 is negatively correlated to the increase in plasma viscosity during exercise (r = -0.546, p < 0.05), suggesting that this event is less important in stronger individuals. This study shows that fat mass, even within a physiological range, is a determinant of erythrocyte aggregability, suggesting that training-induced alterations in body composition play a role in the specific hemorheologic profile of athletes. In addition, both erythrocyte flexibility and the magnitude of fluid shifts during exercise appear to be related to fitness in these sportsmen.

Adipose Tissue↗

Serum levels of insulin-like growth factor-I are related to age and not to body composition in healthy women and men.

BACKGROUND: Aging is accompanied by decreased bone and lean body mass, increased fat mass, and reduced growth hormone (GH) axis function, reflected in diminished levels of insulin-like growth factor-I (IGF-I). Similar changes in body composition occur in nonelderly, GH-deficient adults and are reversible with GH administration, suggesting that diminished GH/IGF-I axis activity may contribute to such age-related changes. To determine the precise pattern of IGF-I decline with age, and to test the hypothesis that this decline is related to concomitant changes in body composition and bone metabolism independent of age, we conducted a cross-sectional survey in 351 healthy participants in the Baltimore Longitudinal Study of Aging. METHODS: We evaluated relationships among IGF-I, age, and total and regional adiposity, as assessed by body mass index (BMI) and waist-to-hip ratio (WHR); lean body mass, as estimated from urinary creatinine excretion (Crex/ht); bone mineral density (BMD), as assessed by single and dual photon absorptiometry scanning; and circulating levels of parathyroid hormone (PTH), 1,25-(OH)2 D3, 25-OHD, and osteocalcin. RESULTS: Serum IGF-I levels declined with age (p < .0001) in both men (r = -.51) and women (r = -.67). In men, the decline was linear, whereas IGF-I levels decreased faster in women < 45 years of age than in older women (p < .01) or in men (p < .001). IGF-I was inversely related to BMI (p < .005), WHR (p < .001), and PTH (p < .01) in women. IGF-I was positively related to BMD of the hip and radius in both genders (p < .0003) and to Crex/ht (p < .0005) and osteocalcin (p < .0001) in men. With increasing age, Crex/ht and BMD decreased (p < .0001) and WHR, PTH, and osteocalcin increased (p < .005) in both genders, whereas BMI increased only in women (p < .005). After adjustment for age, IGF-I was not significantly related to BMI, WHR, Crex/ht, or BMD in either gender. IGF-I was positively related to 1,25-(OH)2 D3 (p < .01) independently of age in women. CONCLUSIONS: Advancing age, rather than declining serum levels of IGF-I, appears to be a major determinant of life-time changes in body composition and BMD in women and men.

Adult↗

Neonatal body composition: dual-energy X-ray absorptiometry, magnetic resonance imaging, and three-dimensional chemical shift imaging versus chemical analysis in piglets.

An animal study to evaluate dual-energy x-ray absorptiometry (DXA) and magnetic resonance (MR) imaging and spectroscopy for measurement of neonatal body composition was performed. Twenty-three piglets with body weights ranging from 848 to 7550 g were used. After measuring total body water, animals were killed and body composition was assessed using DXA and MR (1.5 T; MR imaging, T1-weighted sagittal spin-echo sequence; MR spectroscopy, three-dimensional chemical shift imaging) as well as chemical carcass analysis (standard methods) after homogenization. Body composition by chemical analysis (percent of body weight, mean +/- SD) was as follows: body water, 75.3 +/- 3.9%; total protein, 13.9 +/- 8.8%; and total fat, 6.5 +/- 3.7%. Absolute content of fat and total ash was 7-674 and 35-237 g, respectively. Mean hydration of fat-free mass was 0.804 +/- 0.011 g/kg and decreased with increasing body weight (r2 = 0.419) independent of age. Using DXA, bone mineral content was highly correlated with calcium content (r2 = 0.992), and calcium per bone mineral content was 44.1 +/- 4.2%. DXA fat mass correlated with total fat (r2 = 0.961). Using MR, spectroscopy and chemical analysis were highly correlated with fat-to-water ratio (r2 = 0.984) and absolute fat content (r2 = 0.988). Total fat by MR imaging volumetry showed a lower correlation (r2 = 0.913) and overestimated total fat by a factor of 2.46. Conversion equations for DXA were developed (total fat = 1.31 x fat mass measured by DXA--68.8; calcium = 0.402 x bone mineral content + 1.7), which improved precision and accuracy of DXA measurements. In conclusion, both DXA and MR spectroscopy give accurate and precise estimates of neonatal body composition and may become valuable tools for the noninvasive assessment of neonatal growth and nutritional status.

Absorptiometry, Photon↗

A comparison of methods of assessment of body composition including neutron activation analysis of total body nitrogen.

Fourteen healthy men underwent determinations of total body nitrogen (TBN) by prompt gamma neutron activation analysis and total body potassium (TBK) by whole body counting to estimate the muscle and nonmuscle components of the fat-free body mass (FFBM) and their protein contents. Comparison of FFBM estimated from TBN and TBK (60.6 +/- 6.9 kg, mean +/- SD), densitometry (62.3 +/- 7.1 kg), TBK alone (62.2 +/- 8.0 kg) and TBW (63.9 +/- 7.8 kg) showed no differences among the techniques. Similarly, there were neither differences in fat mass nor percent body fat among the methods. Analysis of the chemical composition of FFBM of this group showed TBK/FFBM = 62.6 +/- 2.3 mEq/kg, TBW/FFBM = 74.6 +/- 0.2%, TBN/FFBM = 32.74 +/- 1.09 g/kg, protein/FFBM = 20.5+/- 0.7%. The calculated mineral content of the FFBM was 6.4%. These values are strikingly similar to the values calculated by direct chemical analysis. It was concluded that the combined TBN-TBK method is a valid technique for estimating body composition in man.

Adipose Tissue↗

Growth, nutritional status, body composition, and energy expenditure in prepubertal children with Alagille syndrome.

OBJECTIVES: To describe the patterns of growth, nutritional status, body composition, and resting energy expenditure (REE) in prepubertal children with Alagille syndrome (AGS) before the onset of end-stage liver disease. STUDY DESIGN: Thirteen prepubertal subjects with AGS (8 male; mean age, 6.8 2.8 years) were evaluated for growth parameters, body composition by skinfolds and by dual-energy x-ray absorptiometry, and REE by indirect calorimetry. The children with AGS were compared with a healthy, age-matched reference group of 37 prepubertal children. RESULTS: Compared with healthy children, children with AGS had significantly reduced (P <. 05) growth (weight, weight z score, height, height z score), nutritional status (midarm circumference, triceps skinfold, and midarm muscle area), and body composition (fat mass and fat-free mass). Subscapular thickness, percent body fat, and REE were not different. The AGS subgroup (n = 4) with REE greater than 110% predicted value had a reduced percent body fat (P <.02). CONCLUSIONS: Growth and body composition abnormalities are common in prepubertal children with AGS.

Alagille Syndrome↗

Body composition in nonalcoholic cirrhosis: the effect of disease etiology and severity on nutritional compartments.

BACKGROUND/AIMS: Previous studies of body composition in cirrhosis have either measured only one body compartment, used alcoholic subjects, or not corrected body composition for physical characteristics. The aim of this study was to perform a detailed analysis of body composition in subjects with nonalcoholic cirrhosis. METHODS: Simultaneous measurements of total body potassium and total body water were performed and values of body cell mass and body fat were corrected for physical characteristics. RESULTS: Child's class C patients had a significantly lower mean total body potassium index (i.e., percent observed value/expected value) and body fat index than class A or B patients. Eighty-one percent of class C patients had simultaneous reductions in body fat and body cell mass, and 71% of patients with class A disease had a significant reduction in either or both compartments. Nine patients showed the pattern of tissue loss seen with short-term starvation. Fourteen patients showed the pattern of tissue loss seen in physiological stress. CONCLUSIONS: Severe liver disease is characterized by significant reductions in body fat and body cell mass, most class A patients have a significant reduction in some nutritional compartments, and the pattern of tissue loss may reflect mechanisms of tissue wasting.

Adipose Tissue↗

Plasma adipokines and body composition in response to modest dietary manipulations in the mouse.

OBJECTIVE: The relationship between adipokine levels and body composition has not been carefully examined. Most studies in humans are cross-sectional, and the few studies in mice have been restricted to a comparison of control animals with markedly obese, insulin-resistant mice. Our objective was to study changes in adipokine levels and body composition in response to modest dietary intervention. RESEARCH METHODS AND PROCEDURES: Plasma resistin, adiponectin, and leptin levels were examined in mice fed ad libitum, a 75% restricted diet, or a diet supplemented with 10% sucrose. Body composition was determined by whole-body DXA. RESULTS: The percentage body fat was reduced in mice subjected to the restricted diet and increased in mice supplemented with 10% dextrose. Adipokine levels were not different in either of these groups compared with the control mice. A significant inverse correlation was observed between resistin levels and total body fat, whereas there was no significant correlation between body fat and adiponectin levels. Positive correlations were observed between leptin levels and percentage body fat, total body fat, and abdominal fat. Leptin levels correlated with plasma glucose, but multivariate analysis revealed that this correlation was the result of a strong positive correlation between leptin and insulin levels. There were no correlations between glycemia and resistin or glycemia and adiponectin levels, and no correlation was observed between any of the adipokine levels and bone mineral content or density. DISCUSSION: These data suggest that in the mouse, modest dietary perturbations have little effect on resistin and adiponectin levels despite significant effects on glycemia, insulin levels, and bone parameters.

Adiponectin↗

Neutron activation analysis determination of body composition.

The nutritional status of patients can be evaluated by monitoring changes in body composition, including the depletion of protein and muscle, adipose tissue distribution and changes in hydration status, bone or cell mass. Neutron activation analysis is a unique reference tool for the in-vivo determination of body composition. In this review we describe the recent changes in the field that followed the advent of new portable generators of fast neutrons, capable of performing elemental analysis in the clinical environment. New models were developed based on the partition of the measurable elements of the body. The recent developments help evaluate new treatments for wasting and obesity, in which change in body composition is the main outcome.

Adipose Tissue↗

[Possibilities for determining body composition of man in relation to obesity].

The following methods for determining the body composition of obese individuals were compared: hydrostatic weighing; determination of total body water (distribution of antipyrine and of tritium oxide); determination of the total potassium content of the body; determination of the amount of excreted creatinine. The values for body fat which derived from the body density, from the total potassium content and from the distribution of antipyrine differed only to a small extent. These differences were not significant. But the value based on tritium oxide distribution differed significantly. The study of the body composition of obese individuals has clearly shown that the increase in body weight is significantly correlated with the increase in the proportion of fat in the body (r=0.444), with the increase in the absolute fat content (r=+0.898) and also with the increase in the proportion of lean body mass (r=0.826). Not only the fat (61.2%) but also the lean body mass (38.8%) contributes to the weight increase of obese individuals. The quantitative determination of the fat content of the body and of the fat-free substance not only serves to specify the diagnosis of obesity (in particular, it permits to detect the so-called latent obesity) but is also the basis of the assessment of certain function, e.g., energy metabolism. The effectiveness of different methods for losing weight may be evaluated by repeated determinations of the fat content and for the lean body mass.

Adipose Tissue↗

Stable isotopes and bioelectrical impedance for measuring body composition in infants born small for gestational age.

The assessment of body composition in infants born small for gestational age (SGA) is required primarily to evaluate nutritional status and to monitor growth in the neonatal period. Measurement of total body water, using stable isotopes of hydrogen (2H) and oxygen (18O), offers a potential method by which body composition can be assessed. This technique is non-invasive and recently has been used successfully in a cohort of 5-week-old infants born SGA. Nevertheless, the assessment of total body water using stable isotopes requires specialized laboratories and equipment, which may limit its use. Prediction of total body water by bioelectrical impedance is a possible alternative. This technique uses electrical theory to predict the volume of the conducting medium in the body, namely, water. A potential limitation of bioelectrical impedance analysis is the accuracy, which may impinge on its usefulness in small infants.

Body Composition↗

Cross-trait familial resemblance for resting blood pressure and body composition and fat distribution: The HERITAGE family study.

Cross-trait familial resemblance between resting blood pressure (BP) and body composition and fat distribution was examined in 98 Caucasian families participating in the HERITAGE Family Study by using a multivariate familial correlation model assessing both intraindividual and interindividual cross-trait correlations. The 520 family members were sedentary at baseline examination, and both resting systolic (SBP) and diastolic (DBP) BP were cross-analyzed with each of the following 10 indications of body composition and fat distribution: percent body fat (%BF), abdominal visceral fat (AVF), body mass index (BMI), fat-free mass (FFM), fat mass (FM), sum of eight skinfolds (SF), total abdominal fat (TAF), ratio of trunk-to-extremity skinfolds (TER), waist circumference (WAIST), ratio of waist-to-hip circumferences (WHR). Five of the variables were also corrected for fat mass (AVFf, TAFf, TERf, WAISTf, WHRf) to index these measures independent of total degree of adiposity. In general, the results suggested strictly intraindividual cross-trait resemblance, with occasional spouse cross-trait resemblance, but few or no sibling or parent-offspring cross-trait correlations. This pattern is largely consistent with nongenetic specific environmental determinants for the BP-body composition and fat distribution covariation, with possibly some common environmental influence between spouses and negligible genetic effects. The only findings suggesting any familial cross-trait resemblance were significant sibling correlations for DBP-FFM and DBP-WHR, although the parent-offspring correlation was not significant. These findings suggest that the observed BP-body composition and fat distribution cross-trait correlations in these sedentary families are probably not due to multifactorial effects such as polygenic and/or common familial environmental effects. Whether or not other factors such as nonadditive effects are involved warrants further investigation using other methods. Am. J. Hum. Biol. 12:32-41, 2000. Copyright 2000 Wiley-Liss, Inc.

Journal Article↗

Sports science and body composition analysis: emphasis on cell and muscle mass.

Because we are unsure of many of the constants that we use in the calculation of components of body composition, there is a need for a greater number of postmortem analyses in order to prepare better equations for more accurate utilization of indirect noninvasive measurements. At present, most investigators who study active people (including athletes) use techniques that only provide an approximation of body fatness. Because excess fat serves as a burden to the body during transport in the performance of many physical activities, fatness constitutes a variable of concern. Fat-free body weight is usually calculated by difference and serves as a reference for some physiological functions. Although fat-free weight and lean body mass are not the same, most investigators calculate fat-free weight and many use the terms interchangeably. Some of the assumptions and problems in utilizing hydrodensitometry in the calculation of body fatness remain unresolved, such as the true densities of the different gross components of body composition in the young, aged, physically fit, etc. A variety of body composition profiles of different athletes have been published in recent years, which substantially augment efforts initiated in the 1940s and 1950s. The regular employment of a total body water assessment along with hydrodensitometry would improve the accuracy of calculation of body fatness, but the procedure is somewhat expensive in cost and time of subject involvement. In order to extend our knowledge of body composition and to quantitatively ascertain the mass of skeletal muscle, some of the procedures for calculating cell and muscle mass are reviewed including total body potassium, total body nitrogen, creatinine excretion, and 3-methylhistidine excretion. These procedures reveal important information, but require further investigation before we are confident that we are measuring cell or muscle mass. We have focused on 3-methylhistidine excretion because preliminary investigation suggests that it may reveal differences in muscle mass not detected by densitometry.

Adipose Tissue↗

Anthropometric estimation of maternal body composition in late gestation.

OBJECTIVE: To construct a model to estimate maternal body composition in late gestation using anthropometric measurements. METHODS: Twenty healthy pregnant women at 30 weeks' gestation had estimates of body composition using hydrodensitometry, with corrections for residual lung volume, and total body water using H(2)(18)O (development group). Total body water was estimated from (18)O abundances measured by gas-isotope-ratio mass spectrometry. Maternal age, height, weight, and seven skinfold sites were correlated with fat mass using stepwise regression analysis. The anthropometric model to estimate fat mass was then tested prospectively in a second group of 20 subjects and correlated with underwater weighing and total body water measurements (validation group). Statistical analysis used chi(2), paired t and Wilcoxon sign-rank tests. RESULTS: There were no statistically significant differences in maternal demographics between groups. The fat mass of development group subjects using underwater weighing and total body water was 22.7 +/- 7.6 kg. Using the development group, a model was derived that explained 91% of the variance in fat mass by underwater weighing and total body water using maternal weight and triceps, subscapular, and suprailiac skinfolds (r(2) = 0.91, P <.001). When tested prospectively in the validation group, the correlation remained statistically significant (r(2) = 0.89, P <.001). There was no statistically significant (P =.88) difference between the anthropometric estimates of fat mass and underwater weighing and total body water measurements (95% confidence interval -2.476, 2.748 kg of fat mass). CONCLUSION: This anthropometric model can be used to predict maternal fat mass in late gestation.

Adult↗

Anthropometry and body composition in ethnic Japanese and Caucasian adolescent girls: considerations on ethnicity and menarche.

OBJECTIVE: This study aimed to compare the various anthropometric and body composition parameters based on the ethnicity and the absence or presence of menarche. DESIGN: A cross-sectional study with incomplete sampling, using the subject as the evaluation unit. SUBJECTS: The final sample of 550 subjects was composed of 122 Japanese and 179 Caucasian premenarcheal adolescents, and 72 Japanese and 177 Caucasian postmenarcheal adolescents. METHODS: The variables of body composition were measured through the following methods: bioelectrical impedance analysis, near-infrared interactance (NIR), Slaughter cutaneous skinfold equations and body mass index. Weight, height and sitting height were also evaluated. RESULTS: The Japanese pre- and postmenarcheal girls presented lower weight and height values when compared with the Caucasian girls. In general, the Japanese premenarcheal girls presented less fat and fat-free mass than the premenarcheal Caucasian girls. This fact was demonstrated through NIR results. Conversely, the Japanese postmenarcheal adolescents accumulated more fat than their Caucasian counterparts. However, significant differences were solely encountered in the values of cutaneous skinfold percent body fat. With regard to menarche, it was verified that, regardless of ethnicity, all the anthropometric and body composition variables reached higher values among postmenarcheal adolescents when compared with premenarcheal adolescents. CONCLUSION: Different results of weight and height between the ethnic groups may bring back the discussion concerning separate growth curves for different ethnic groups. The results of the body composition analysis indicated high adiposity levels among postmenarcheal adolescents.

Adipose Tissue↗

Exercise training alters feed efficiency and body composition in iron deficient rats.

Studies of body composition and feed efficiency were conducted on 80 male Sprague-Dawley rats to determine how exercise training alters growth and development in iron deficient animals. Animals were assigned to iron deficient (ID) or control (CN) diets (AIN-76, w/o cellulose), and sedentary (SD) or exercised groups [EX, treadmill running, 4 d.wk-1, 90 min.d-1, 65% maximal oxygen consumption (VO2max), maintained for 6 or 12 wk. The ID diet caused a sustained moderate iron deficiency (Hb 7.2 +/- 0.2 g.dl-1). Iron deficient animals failed to increase maximal oxygen consumption despite the rigorous training program, through training resulted in 25% or 35% higher VO2max in 6- or 12-wk CN rats. At 6 wk, IDEX animals had significantly (33%) lower growth rates than did IDSD animals, which in turn were 22% less than CNs. Overall, exercise did not alter relative amounts of protein in the carcass (% total mass); however, a significant interaction between diet and treatment duration was evident in IDEX animals at 12 wk, who had lower % protein than CNEX-12 or IDSD-6 rats. Training decreased fat 11% in CN at 6 wk but not 12 wk, and 20% in IDs at 12 wk but not 6 wk. Feed efficiency and energy intake were 28% and 12% lower in IDEX animals than CNEX at 6 wk. Training increased caloric intake in CNEX animals but not IDEX animals at 6 and 12 wk. Thus, exercise training exacerbates the poor growth associated with ID through alterations in both food intake and feed efficiency in early phases of training, but adaptation is apparent.

Animals↗