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PubMed2004

Body composition changes in bodybuilders: a method comparison.

INTRODUCTION: Few studies report on validation of body composition changes using the four-compartment model (4C), and no such studies are available in strength training. Here we present such a validation study for the determination of body fat and fat-free mass changes in bodybuilders, who used exercise and androgenic-anabolic steroids. METHODS: The study was carried out with 27 male bodybuilders in a cross-sectional study. Fifteen of these subjects also participated in an intervention program where body composition changes were measured. The 4C model served as the gold standard. The alternative mechanistic methods were underwater weighing (uww), deuterium dilution (dil), three-compartment model incorporating total body water (3Cw), three-compartment model incorporating bone mineral content (3Cb), and descriptive methods, namely dual-energy x-ray absorptiometry (DXA), prediction equations based on body mass index (BMI), skinfold measurement, and bioimpedance analyses. RESULTS: From the cross-sectional study, it appeared that biases and errors of most mechanistic methods were small (maximal 0.5% BF and 3.4%BF, respectively; exception 3Cb model). The 3Cw model had the lowest error (0.9%BF). The descriptive methods had small biases (exception BMI) but relatively large errors (range: 5.5-8%). Results on body composition changes (intervention study) were comparable with the results from the cross-sectional study. CONCLUSIONS: Using the 4C model as the standard for determination of body fat and fat-free mass, this study revealed that apart from the prediction equation based on BMI and the 3Cb model, all methods gave acceptable group mean values. When accurate measurements on body composition and/or body composition changes on an individual level are needed, only the 3Cw model could serve as an alternative for the 4C method.

Absorptiometry, Photon↗
PubMedDate not supplied

Validation of body composition assessment techniques in the dialysis population.

Assessment of body composition remains a goal for the routine assessment of nutritional status of patients on long-term dialysis. Methods generally available for estimation of body fat in healthy individuals are limited by practicality and availability for use in this patient population. Anthropometry, which is cost effective and easy to perform, is limited by the lack of appropriate reference standards for patients on dialysis and artifact caused by hydration status. Bioelectrical impedance affords new opportunities for non-invasive assessment of fluid volume, its distribution, and body cell mass; estimation of fat-free mass and body fat can be affected by hydration status. Dual x-ray absorptiometry permits estimation of bone status and fat mass because changes in hydration status are reflected in estimates of fat-free mass. Evaluation of validity of techniques for fluid status and body composition assessment requires the use of appropriate reference methods and proper statistical procedures to examine error, not only between groups, but by individual. Use of body composition assessment methods together with biochemical measurements will enhance the nutritional assessment of end-stage renal disease patients on long-term hemodialysis.

Absorptiometry, Photon↗
PubMed2004

Kinetics of stable isotope and body composition in olive baboons (Papio anubis) estimated by deuterium dilution space: a pilot study.

Morphometrics and isotope-labelled water were used to determine body composition [total body water, total body fat and fat-free mass (FFM)] of three captive female olive baboons (Papio anubis). Mean mass was 16.5 kg, comparable with other captive settings but heavier than wild olive baboons. Average water content was 66%; FFM averaged 90.5%. Baboon females have less body fat than human counterparts. Compared with captive or wild baboons, these females were adequately nourished for their energy expenditure. A positive association between total mass and FFM existed, but due to the small sample no general relationship was observed for body fat or FFM and condition or size measures. The kinetics of deuterium equilibration in body fluids for baboons was determined as 3-4 hours after injection, similar to that for humans. Deuterium dilution technique appears to be an appropriate method for studying body composition in baboons, although a larger sample is needed for relationships between morphometric indices and body composition.

Animals↗
PubMed1986

Effects of peritoneovenous shunting on body composition.

The effect of peritoneovenous shunting on body composition has been studied in 7 cirrhotic patients undergoing a successful shunt and 3 patients in whom the shunt was unsuccessful. In the 7 patients with functioning shunts, their weight had decreased by a mean of 9 kg (p less than 0.001) by 6 wk after initial diuresis, natriuresis, and kaliuresis, and was associated with a decrease in total body potassium (TBK) but not total body nitrogen (TBN). This resulted in a significant decrease in the TBK/TBN ratio from 2.12 +/- 0.74 to 1.66 +/- 0.20 (p less than 0.01). By a mean of 14 mo, in these 7 patients there was a significant increase in mean TBN (from 1.54 +/- 0.10 to 1.84 +/- 0.10, p less than 0.005) associated with an improvement in the mean nitrogen index (from 0.74 +/- 0.04 to 0.88 +/- 0.04, p less than 0.005). These changes were associated with a significant increase in nonalcoholic calories, a nonsignificant increase in protein consumption, and a positive nitrogen balance. After the initial kaliuresis, mean potassium balance remained constantly positive (+22.7 +/- 3.4 mmol/day), serum aldosterone levels normalized, and TBK increased. In contrast, 3 patients with failed peritoneovenous shunting continued to lose weight significantly despite the presence of ascites; TBN and nitrogen index also decreased. In conclusion, body composition studies appear to have confirmed the clinical observation that cirrhotic patients with massive ascites have depleted body protein which is gradually repleted only after successful shunting. In this situation TBK, long used as a measure of lean body mass, is less satisfactory than TBN and nitrogen index. This improvement in body protein appears to be explained by an increased dietary intake associated with improved nitrogen balance, but these changes are not found in patients in whom the shunt failed.

Adult↗
PubMed1976

Effects of dianabol and high-intensity sprint training on body composition of rats.

The effects on body composition and organ weights of anabolic steroid administration and of high-intensity sprint running, separately and in combination, were studied in young adult male rats. Dianabol (methandrostenolone) 1 mg/day for 8 weeks had no significant effects on muscle weight or lean body mass in either the trained or the sedentary animals. The program of sprint training resulted in a lower body weight, a lesser percentage of body fat (Runners, 8.5%, vs. sedentary, 13.5% P less than 0.01) and a greater relative lean body mass (runners, 91.5% vs. sedentry, 86.5%, P less than 0.01). We conclude from these results that (a) normal androgen levels in young, healthy male animals are sufficiently high so that the addition of a large dose of anabolic steroid does not result in stimulation of additional muscle growth, and (b) the changes in body composition induced by high-intensity, short-duration sprint training are qualitatively similar to those seen with endurance exercise training.

Adrenal Glands↗
PubMed1990

Estimation of body composition by bioelectrical impedance in cancer patients.

Measurement of body composition is important in the assessment of nutritional status in cancer patients. The purpose of this study was to validate the bioelectrical impedance (BI) method for body composition estimation in 33 elderly cancer patients (mean age 66 +/- 9 years) using the deuterium dilution technique (2H2O) as the reference method. Height2/Resistance (H2/R) correlated significantly with total body water (TBW) computed from 2H2O (r = 0.89, P less than 0.001; s.e.e. = 2.4 l). The prediction equation for TBW improved significantly (P less than 0.001) by addition of H2/R to the predictor variables weight, height, age and sex. We conclude that BI is a useful measure for the assessment of body composition in cancer patients.

Aged↗
PubMed1990

Evaluation of near infra-red interactance as a method for predicting body composition.

The ability of near infra-red interactance (NIRI) to predict body composition, as measured by whole-body densitometry, was assessed in a group of 29 healthy volunteers; 15 m, 14 f, aged 18-40 years, body mass index (BMI) 18.3-28.5 kg/m2. The results were compared with those obtained by five other predictive methods: whole-body impedance/resistance, skinfold thicknesses, and methods based on weight and height or BMI. The correlation between densitometry and the alternative methods, including NIRI, were found to be remarkably similar, both with respect to fat (r = 0.90-0.92, s.e.e. = 2.12-2.47 kg), and fat-free mass (r = 0.96-0.97, s.e.e. = 2.13-2.71 kg). Percentage body fat (densitometry) correlated better with the near infrared measurements made in the biceps area than with those made in the triceps or thigh areas, or with a combination of measurements made at two or three sites. The 95 per cent limits of agreement between NIRI and densitometry for the estimation of body constituents were slightly greater than those between densitometry and the other methods. NIRI was also found to underestimate body fat increasingly as the degree of adiposity increased. This under-estimation was found to be particularly marked (16 per cent body weight) in a small and separate group of grossly obese women, BMI greater than 50 kg/m2, whose body composition was assessed by total body potassium as well as by densitometry. This study suggests that, in the healthy group of subjects examined, NIRI has little or no advantage over other simple methods in predicting body composition measured by classical whole-body densitometry.

Adolescent↗
PubMed2005

The end of body composition methodology research?

PURPOSE OF REVIEW: Over one century of research has led to methods for measuring all major body components at the atomic, molecular, cellular, and tissue-system levels. These remarkable developments have fueled a rapid and sustained increase in 'body composition' biological findings and related publications. Other than small, incremental improvements in available methods, is there no longer a need for developing new body composition methods? This review examines the question: are we approaching the 'end' of body composition methodology research? RECENT FINDINGS: Emerging and rapidly growing areas outside of 'traditional' body composition research are highlighting the need for new and innovative method development. Recently introduced technologies such as positron emission tomography and functional magnetic resonance imaging extend 'mass' estimates to corresponding 'function' and physiology in humans. Although all major components are now measurable in humans, large gaps remain when considering factors such as radiation exposure, invasiveness, static versus dynamic measurements, and laboratory versus clinic and field assessments. SUMMARY: The end of the first phase of body composition method development has now arrived: all major components are measurable in vivo. The accessibility of these methods is stimulating rapid advances in biological knowledge surrounding human body composition from in utero to old age. Sustaining advances in new body composition method development will require extending the boundaries of the field as it now exists.

Biomedical Research↗
PubMed2000

Anthropometry and methods of body composition measurement for research and field application in the elderly.

Evaluation of body composition is important in the study of human energy and protein metabolism as methods are available for quantifying energy stores and protein content at a single point in time; energy-protein balance can be monitored over time; and dynamic measures of energy and protein metabolism can be referenced to body mass and related measurable components for between-individual comparisons. This review emphasizes the need for considering subject age when developing body composition component prediction models that are applied in elderly populations. An overview of body composition research is provided that emphasizes compartment and level definitions and interrelations. Two broad method categories, mechanistic and descriptive, are then critically examined in relation to their role in energy-protein metabolism and aging research. Our collective review indicates that all major body composition components are now measurable using one or more methods that are based on non age-dependent assumptions. We also found that some methods, particularly descriptive field methods (eg anthropometry), may be based on age-sensitive assumptions and measurements and suggestions for future development of these methods are provided. Lastly, as body composition differences between races, cultures, and countries are now recognized, it would be useful to create international cooperative groups with the aim of developing widely applicable descriptive field methods based on simple available techniques such as anthropometry and bioimpedance analysis.

Aged↗
PubMed2001

A critique of the expression of paediatric body composition data.

There is increasing interest in body composition in paediatric research, as distinct from growth and nutritional status, as almost all diseases have adverse effects on either fatness or the fat-free mass. However, the approaches used to assess growth and nutritional status are not appropriate for separate evaluations of body fatness and lean mass. Traditional measurements such as body mass index and skinfold thickness do not measure fat in accurate quantitative terms. Various techniques have been used in recent years which divide body weight into fat mass and fat-free mass; however, the data tend not to be appropriately expressed. Body fatness is generally expressed as a percentage of weight, while fat-free mass typically remains unadjusted for size. A more appropriate approach is to normalise both body fatness and fat-free mass for height. This recommendation is relevant both to studies comparing patients with controls and to the expression of new reference data on body composition which are needed to allow informative comparisons. The same approach is appropriate for the classification of childhood obesity.

Body Composition↗
PubMed1986

Growth, body composition and breast milk intake of Swedish infants during early life.

The growth and breast milk intake of 22 healthy completely breast fed Swedish infants (9 girls, 13 boys) during the first 10 wk of life are reported and were found to be similar to those of other healthy breast fed populations of infants. Also the body composition (body fat and lean body tissue) was estimated by an anthropometric method at the age of about 10 and 65 days. It was found that the breast milk intake correlated significantly with weight and fat gain but not with gain in lean body tissue or with gain in length. These findings suggest that energy rather than protein intake limited growth in this group of infants. Also the results confirm the fact that the capacity for fat retention is high during early life and show that the size of fat stores is related to breast milk intake.

Body Composition↗
PubMedDate not supplied

Longitudinal changes in body composition in women approaching the midlife.

This population-based longitudinal study describes the 4.5-year changes in body composition and body mass distribution in women aged 20-45 years, and characterizes predictors of these changes. Body weight, waist-to-hip ratio, Quetelet index, fat and lean body mass were measured in 404 white menstruating women aged 20-40 at baseline and 4.5 years later (follow-up). Variables considered for predicting body composition differences were hormonal status, menstrual status, parity, diet and physical activity. Average body weight increased 4.3 kg in 4.5 years (6.4 kg increase in fat and 2.1 kg decrease in lean)--a net increase of 7.1% total body fat. Measured predictors were not significantly associated with weight or Quetelet index; however, they were associated with measured amounts of lean and fat. Longitudinally, women who preserved the most lean body mass tended to be nulliparous, to be still menstruating, to have higher testosterone levels, and to smoke. Physical activity was associated with preserving lean body mass. Increasing age and higher follicle-stimulating hormone levels were associated with increasing waist-to-hip ratio. Average body weight showed a steady increase--characterized by an expanding fat compartment and a shrinking lean compartment--with the older women increasing more in waist girth relative to hip girth than younger women. Predictor variables of these changes included hormonal environment, physical activity, smoking behaviour, parity, and oophorectomy.

Adipose Tissue↗
PubMed2002

Body composition in early onset eating disorders.

BACKGROUND: Body mass index (BMI) or equivalent weight for height indices are the most widely used measures of body composition in early onset and adolescent eating disorders. Although of value as screening instruments the limitation in disease states is their inability to discriminate fat and fat-free components of body weight. OBJECTIVE: To compare height-adjusted fat and fat-free components of body composition in children and young adolescents with different types of eating disorders with those of age matched reference children. DESIGN: Weight, height, triceps and subscapular skinfold thickness were measured in 172 children (aged 7-16 y) with eating disorders receiving specialist treatment. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated using Slaughter's and Deurenberg's equations and normalisation for height. Using data from 157 normal children, representative of the UK 1990 growth reference data, reference curves for FMI and FFMI+/-2 s.d. were derived. Results for patient groups were superimposed on these reference curves. RESULTS: FMI and FFMI were both reduced in eating disorders associated with malnutrition, including anorexia nervosa (AN). AN subjects did not differ from other subjects with comparable degrees of malnutrition. Children with eating disorders of normal weight, such as bulimia nervosa and selective eating, did not differ significantly from reference children in their relative FM and FFM. CONCLUSIONS: FM and FFM merit independent consideration in disorders of malnutrition in children, rather than expressing data as percentage body fat or percentage BMI. The implications of loss of FFM on growth and development merit further investigation.

Adipose Tissue↗
PubMed1998

Beneficial effects of one-year growth hormone administration to children with juvenile chronic arthritis on chronic steroid therapy. I. Effects on growth velocity and body composition.

Severe growth retardation and profoundly altered body composition are observed in children with systemic forms of juvenile chronic arthritis receiving glucocorticoids. The purpose of this study was to assess the effects of recombinant human GH (rhGH) on growth velocity (GV) and body composition studied by dual-energy X-ray absorptiometry, during a 1-yr treatment course, together with potential adverse effects on glucose tolerance. Fourteen patients were treated with rhGH (1.4 U/kg per week) for 1 yr and were then studied for a 2nd yr off GH. Baseline GH secretion, GH binding protein (BP), insulin-like growth factor-I (IGF-I), and IGFBP3 levels were at the lower limit of normal. The rhGH treatment increased IGF-I and IGFBP3 plasma levels to above-normal values. All patients showed an increase in GV, and mean GV increased from 1.9-5.4 cm/yr (P < 0.001). Compared with the value on day 0, lean body mass increased by 12.2% (P < 0.01), and the fat mass excess fell by 19.5% (P < 0.01). Decreased glucose tolerance (as determined by oral glucose tolerance test) and increased glycosylated hemoglobin levels were observed during treatment. This effect may be attributed to insulin resistance, as reflected by induced hyperinsulinemia. Eleven children were monitored for 1 yr after the cessation of GH therapy. GV fell to pretreatment values, whereas height in SD score at the end of the 2nd yr was lower (P < 0.01) than before treatment. Weight and fat mass again increased markedly. Although long-term controlled studies are needed to assess the risks and benefits of GH therapy in this setting, our results suggest that rhGH may partially counteract the adverse effects of glucocorticoids on growth and metabolism in patients with chronic inflammatory disease.

Absorptiometry, Photon↗
PubMed1990

Validation of bioelectrical-impedance analysis as a measurement of change in body composition in obesity.

The bioelectrical-impedance-analysis (BIA) method accurately measures body composition in weight-stable subjects. This study validates the use of BIA to measure change in body composition. Twelve obese females underwent weight loss at a mean rate of 1.16 kg/wk. Body composition was measured by deuterium oxide dilution (D2O), BIA, and skinfold anthropometry (SFA) at baseline and at 5% decrements in weight. Highly significant correlations were obtained between D2O and BIA (r = 0.971) and between D2O and SFA (r = 0.932). Overall, BIA predicted change in fat-free mass with greater accuracy (to 0.4 kg) and precision (+/- 1.28 kg) than did anthropometry (to 0.8 kg and +/- 2.58 kg, respectively). We conclude that BIA is a useful clinical method for measuring change in body composition.

Adult↗
PubMed2002

Body composition in a seasonal model of obesity: longitudinal measures and validation of DXA.

OBJECTIVE: Collared lemmings, Dicrostonyx groenlandicus, show rapid changes in body mass on a seasonal basis. The objective of this study was to measure longitudinal changes in body composition in animals undergoing photoperiod-induced weight gain and loss using DXA. RESEARCH METHODS AND PROCEDURES: Adult, female collared lemmings exposed to either long (LD; 22 hours light/2 hours dark) or short (SD; 8 hours light/16 hours dark) photoperiods were anesthetized, and DXA was used to determine fat mass, lean tissue mass (LTM), total-body bone mineral content, and total-bone mineral density. After a baseline scan, one-half of the animals were transferred to the alternate photoperiod (SD-LD, weight loss; LD-SD, weight gain) and one-half remained on the same photoperiod (controls; SD-SD, LD-LD). Body composition was determined by DXA after 4 and 8 weeks. Animals were killed, and body composition was determined by carcass analysis. DXA-derived data were validated by comparing with carcass analysis. RESULTS: Body composition by DXA was highly related to body composition measured by chemical analysis, thereby justifying the use of DXA. Lemmings in the SD-LD group lost weight, and this was reflected in measurable losses of fat and LTM. Lemmings in the LD-SD group gained weight, which was shown by measurable increases in fat, LTM and total-body bone mineral content. DISCUSSION: Comparison of body composition determined by DXA to that by chemical extraction revealed that DXA is useful for measuring body composition. The longitudinal analysis revealed that collared lemmings undergo rapid changes in body composition when exposed to changes in photoperiod.

Absorptiometry, Photon↗