Body composition and anthropometry in bodybuilders: regional changes due to nandrolone decanoate administration

The purpose of the present study was to investigate regional changes in body composition and anthropometric variables induced by nandrolone decanoate in bodybuilders. In a randomized, double blind, placebo controlled design 16 subjects received weekly intramuscular injections containing 200 mg nandrolone decanoate (ND) or placebo. Composition of total body and body parts were assessed using dual energy X-ray absorptiometry (DEXA), skinfolds and circumferences. Measurements were performed at baseline, after 8 weeks ND administration period and 6 weeks after drug withdrawal. DEXA revealed that total body mass (from 76.16 +/- 2.70 to 78.73 +/- 4.07 kg, p<0.5) and bone-free lean mass (from 59.54 +/- 2.36 to 63.06 +/- 2.99 kg, p < 0.025) increased significantly during ND administration whereas bone mineral mass remained unchanged. Six weeks after drug cessation bone-free lean mass was still increased compared to baseline levels. During ND administration significant increments of bone-free lean mass of the trunk (+ 2.03 kg) and legs (+ 1.08 kg) could be observed. Percentage fat of the legs decreased during the drug intervention period (-1.9%) and remained lowered six weeks after drug withdrawal. No alteration in any variable of the arms was observed. Skinfolds did not change during the entire study period in both groups. After 8 weeks ND administration circumference of the neck was increased (+0.9 cm) significantly although all circumferences underwent non-significant gains. In conclusion, the intramuscular administration of nandrolone decanoate (200 mg per week) during eight weeks induced an increase of body weight and bone-free lean body mass in bodybuilders that was mainly situated in the trunk and legs as determined by DEXA. The changes in the trunk were reflected in the circumferences but not the alterations in the legs. Skinfolds were not able to detect changes of fat mass of body parts. DEXA revealed that total fat mass and total percentage fat remained unaffected by drug administration while percentage fat of the legs decreased and remained lowered after drug cessation. These data indicate that changes of the composition of body parts induced by ND are elucidated less accurately by circumferences or skinfolds rather than by DEXA.     

Body composition in dancers: the bioelectrical impedance method

PURPOSE: The aim of this study was to generate and validate a prediction equation for estimating the body composition in dancers using the bioelectrical impedance analysis (BIA) as a method of assessment. METHODS: The fat-free mass (FFM) of 42 young female professional dance students was estimated by four different methods: dual x-ray absorptiometry (DXA), BIA, simple anthropometry, and skinfold thickness; DXA was used as a criterion method. RESULTS: The dancers' FFM was 42.6 kg (SD: 3.3) and, on the average, body fat represented the 19.4% (SD: 4.3) of their body weight. Two dancer-specific BIA equations for the prediction of FFM (E(BIA)) were developed by multiple regression analysis using weight, height, resistance index, and triceps as predictor variables (E(BIA) and E(BIA-TRICEPS)). The validity of these equations as well as of those previously reported was assessed in two randomly selected subgroups of the initial study group, as described by the Bland-Altman analysis. The bias and the limits of agreement of the equations developed in the present study were lower than those resulting from the application of the previously used equations of Segal et al. and Hergenroeder et al. It was also found that, when validated against DXA, skinfolds measurements did not accurately predict body fatness in this group of young females. CONCLUSION: The new equations allow for an accurate routine assessment of body composition in young female dancers by using the method of BIA. Further studies are needed for the cross-validation of the equations in various groups of dancers.     

Body composition of table tennis players: comparison between performance level and gender

The purpose of this study was to compare whole-body and segmental body composition variables of trained Brazilian table tennis players, according to different performance levels and gender. Sixty-four table tennis players (45 male and 19 female) were distributed in three groups according to performance level: international level players (ILP; 12 male; 8 female), national level players (NLP; 14 male; 6 female) and regional level players (RLP; 19 male; 5 female). The anthropometry measurements and body composition analysis were performed using Dual energy X-ray absorptiometry. Male players demonstrated higher fat-free mass (FFM), and lower fat mass (FM) and body fat percentage (%BF, p < 0.05) compared to female players in all competitive levels, however, non-significant differences were found between whole-body composition and performance level. In the comparison between the dominant and non-dominant arms, FFM, fat-free soft tissue mass (FFSTM) and bone mineral density (BMD) were higher in the dominant arm (p < 0.05) compared to the non-dominant arm in all competitive levels, however, the male ILP group presented lower FFM and FFSTM in the dominant arm compared to the NLP, while the female ILP group presented higher BMD compared to the NLP and RLP. In conclusion, male table tennis players presented higher FFM and lower FM and %BF than female players and the dominant arm presented higher FFM and BMD than the non-dominant, possibly due to the mechanical impact-load imposed by time of table tennis practice.     

Body composition measurement in highly trained male athletes. A comparison of three methods

BACKGROUND: The purpose of the present study was to evaluate the differences in the body composition estimate of highly trained male athletes by three different methods: dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA) and skinfold thickness measurement (SFT). METHODS: The study occurred during a non-intensive training period. The measurements were performed at the Human Physiology laboratory. Participants: forty-three male athletes (19 waterpolo, 9 judo, 15 karate) who exercised regularly at least three hours per day, six days per week. Measurements: DXA, BIA and SFT measurements of percentage fat mass (%FM) and the amount of fat-free mass (FFM) were performed. Statistical analyses: the different %FM estimates by the three methods were compared using a one-way ANOVA, with posthoc Bonferroni test when values were significantly different. The same test was used to compare FFM values. The coefficient of variation (CV%=100xSD/mean) was calculated for each methods. Methodological differences among the various methods were analysed with the method of Bland-Altman. RESULTS: ANOVA test showed significant differences among the three methods. In particular, DXA significantly (p<0.001) overestimated %FM (12.4+/-4.1%) and underestimate FFM (67.0+/-6.9 kg) respect to SFT (7.8+/-0.9 % and 71.0+/-8.2 kg) and BIA (9.9+/-1.4% and 69.4+/-7.9 kg). Also Bland-Altman comparison among the estimates indicated wide differences between methods. CONCLUSIONS: DXA provides different body composition estimates than those derived from skinfold thickness measurement and BIA, so that the methods should not be used interchangeably.     

Body composition in athletes: assessment and estimated fatness

The study of body composition attempts to partition and quantify body weight or mass into its basic components. Body weight is a gross measure of the mass of the body, which can be studied at several levels from basic chemical elements and specific tissues to the entire body. Body composition is a factor that can influence athletic performance and as such is of considerable interest to athletes and coaches. This article provides an overview of models and methods used for studying body composition, changes in body composition during adolescence and the transition into adulthood, and applications to adolescent and young adult athletes.     

Exercise-dependence in bodybuilders: antecedents and reliability of measurement

AIM: The purposes of this study were: a) to examine social and psychological antecedents of bodybuilding dependence (life satisfaction, socio-economic status, marital status and parental status) and b) to examine the test-retest reliability of the Bodybuilding Dependence Scale (BDS). METHODS: One hundred and eighty-one male bodybuilders agreed to participate in the study. Nineteen of these failed to complete the questionnaire on the second occasion, resulting in a sample size of 162. Each participant completed the BDS on two occasions 3 weeks apart, together with the Satisfaction with Life Scale (SWLS) and items relating to occupation, marital status and parental status. RESULTS: Pearson correlations revealed high test-retest reliability for all three subscales (r=0.94, 0.96 and 0.94 for social-dependence, training-dependence and mastery-dependence, respectively). Pearson correlations also revealed significant negative correlations between all three BDS subscales and SWLS scores (r=-0.66 in all cases). A MANOVA revealed that working class participants scored significantly higher on all three BDS subscales than intermediate class participants who, in turn, scored significantly higher than professional class participants. Participants who were not currently involved in a romantic relationship scored significantly higher on all BDS subscales than those who were romantically involved. Parents scored significantly higher than non-parents on social and mastery-dependence, but not on training-dependence. CONCLUSION: These results show acceptable test-retest reliability for all three BDS subscales. They also demonstrate that life satisfaction, socio-economic status, marital status and parental status can successfully predict BDS scores.     

Body composition in paraplegic male athletes

The body composition and anthropometric characteristics of male paraplegic athletes (PARA, N = 22) were contrasted to an able-bodied ectomorphic (N = 22) and mesomorphic (N = 31) comparison group of moderately and highly trained male subjects. The validity of 12 body composition [density (Db)] prediction equations reported in the literature, 4 generalized, were determined (tested) on this special group of athletes (PARA). On the whole, the prediction equations over-predicted Db in PARA by 0.0039 to 0.0166 g X cm-3 (under-predicted relative fat by 1.8 to 7.4%). Five diameter, 11 circumference, and 7 skinfold measures were used in a SAS-STEPWISE multiple regression procedure with hydrostatically determined Db to develop several suitable Db prediction equations for the paraplegic athlete. Diameters were poor predictors (r = 0.60, SEE = 0.0164), while skinfolds, circumferences, or a combination of measures were acceptable, with the combined equation being best (r = 0.95, SEE = 0.0064). The findings of this study suggest that even generalized equations do not adequately predict Db in PARA and that paraplegic specific equations are presently best suited for predicting Db in paraplegic athletes. The results further indicate that although these equations meet many of the criteria of Lohman, the SEE and total error values are unusually high and make prediction of body composition using anthropometry in a heterogeneous group of PARA athletes slightly unreliable.     

Body composition and performance in cross-country skiing

The purpose of this study was to investigate the relationships between body composition and performance in cross-country skiing. Ten male college-aged elite cross-country skiers (17.9 yrs; S 1.0 yrs) participated in a 5.6-km cross-country skiing time trial and in dual energy X-ray absorptiometry (DXA, Lunar DPX-L, Madison, WI, USA) body composition measurements. A differential global positioning system (dGPS, GPS 12 CX, Garmin Int. Inc., Olathe, KS, USA; RXMAR 2, Aztec SA, Strasbourg, France) was used to compute speed in different sections of the course. Spearman correlation analyses were applied. Total body weight and absolute lean body mass were significantly related to final time (r = - 0.721; p < 0.05 and - 0.830; p < 0.01, respectively). Absolute lean arm mass (kg) was negatively correlated to final time (r = - 0.648; p < 0.05) and the relative lean arm mass was significantly related to speed mainly in uphill sections (r = 0.636 to 0.867; p < 0.05 to p < 0.01). We suggest that large amounts of lean body mass, especially in the arms, seem to be of great importance for cross-country skiing performance.     

Body composition and menstrual function in athletes

The problem of menstrual dysfunction in athletes was recognised at about the same time as a theory was developed that a critical fat level was necessary for the onset and maintenance of menstrual function (17% and 22% of bodyweight, respectively). This theory was acceptable because of the frequency of leanness in athletes experiencing menstrual dysfunction and because of the role of adipose tissue in the intraconversion of hormones which could affect hypothalamic and pituitary regulatory centres. Research on this topic has been hampered by the extensive use of surveys, confining sampling to specific sports, use of inaccurate methods of body composition assessment, and lack of data on hormonal changes. Studies using appropriate body composition measures do not support the critical fat theory, but they do not exclude a role for body composition changes in the regulation of menstrual function. The probability of finding menstrual dysfunction in very lean athletes is high, but not absolute, and there is no assurance that dysfunction will improve merely by increasing bodyweight. Perhaps of more concern, however, is recent research on very lean, long term amenorrhoeic athletes who train intensely and show a loss of bone mineral, apparently related to low oestrogen levels. This mineral deficiency is apparently a factor in stress fractures. The bone mineral content of these athletes is similar to that of post-menopausal women susceptible to osteoporosis. Although the loss of bone due to short term amenorrhoea may be reversible, the prognosis for a long term deficiency is not presently known.     

Body composition prediction in university football players

This study was intended to determine if previously-developed body composition prediction equations were valid for use with a Division I university football team. A sample of 68 Division I football players with a mean age of 19.7 yr, was assessed for body density (BD) by underwater weighing (UWW), residual volume by helium dilution, and 26 selected anthropometric measures. A predicted BD was obtained by using two sets of equations developed from college football players and from three generalized equations. The differences between predicted and observed body densities were analyzed. Seven of the nine models examined failed to accurately predict the BD for this population of university football players. One sport-specific equation of White, Mayhew, and Piper for individuals in the backfield and a generalized model of Jackson and Pollock (JP) containing two circumferences performed well when considering the mean of differences and the magnitude of total error relative to the published standard error. However, both of these models overestimate body density for players with low BD and underestimate BD when actual BD is high. Using the JP model for a player whose actual BD is near the sample mean of 1.070, the estimated mean is very close at 1.069. However, for players with actual BD of 1.050, the estimated mean is 1.054, and if actual BD is 1.085, the JP estimated mean is 1.078. The bias is linear between these points.     

Body composition and hematological changes following ascents of Mt. Aconcagua and Mt. Everest

Both Mt. Aconcagua (22,841.2 ft/6962 m) and Mt. Everest (29,035.4 ft/ 8850 m) are highly prized summits by mountaineers, yet there are no published studies comparing the physiological adaptations that occur from climbing both peaks. This case study compares the changes in body composition and hematology of a mountaineer who ascended both peaks. The male subject was 41 yr of age during the Aconcagua ascent and 43 yr of age during the Everest ascent, and had a history of ascents above 19,685 ft (6000 m). Baseline body composition measurements and blood draws were done within a few days of departure for both expeditions. Body composition was assessed by air displacement plethysmography and the blood draw consisted of a complete blood count (CBC). Post-expedition measurements were taken 10-14 d after reaching the summits. The ascent of Aconcagua resulted in a 2.0-kg drop in body mass and a reduction in body fat (15.5% to 12.1%), but blood chemistry remained within +/- 2% of baseline values. Body mass was reduced from 65.0 kg to 60.5 kg during the Everest expedition with a drop in body fat from 17.3% to 10.2%. Despite no change in RBCs there were increases in hemoglobin and mean corpuscular hemoglobin of 12.7% and 13.7%, respectively. It took the subject 12 d to reach the summit of Aconcagua, whereas it took 50 d to reach the summit of Everest. The longer duration at higher altitude for the Everest expedition resulted in more dramatic physiological changes.     

Body composition in sport and exercise: directions for future research

Body composition has become a major field of interest for many exercise and sport scientists as well as clinicians who specialize in the prevention of and rehabilitation from hypokinetic diseases. This paper discusses the state of the art within selected areas of body composition, identifying significant areas of controversy and proposing specific problems where research should be focused. The areas addressed include the following: the use of body density to estimate relative body fat in selected populations, the use of anthropometric equations to estimate body composition, body composition assessment for profiling and counseling athletes, and alterations in appetite and body composition resulting from acute bouts of exercise and from exercise training.     

Body composition analysis in obesity: radionuclide and non radionuclide methods

Body composition (BC) assessment provides important information regarding the absolute or relative amount of bone, lean and fat tissue. Different somatometric techniques have been applied in numerous epidemiological and experimental studies, as well as in every day clinical practice. Traditional techniques for BC analysis include skin fold thickness measurements, radioisotope dilution methods, hydrodensitometry and underwater weighing, while newer techniques include bioelectrical impedance analysis (BIA), air displacement plethysmography (ADP), dual energy X-rays absorptiometry (DEXA), computer tomography and magnetic resonance imaging. In addition, positron emission tomography helped to the functional investigation of adipose tissue, in particular of brown tissue. All these techniques have contributed a lot to the understanding of physiological conditions such as exercise training, menopause and ageing, adolescence health parameters, as well as pathological conditions such as disorders of nutrition, cancer, obesity and diabetes mellitus. In obesity, BC contributed to diagnosis and the pathological impact of visceral adipose tissue. In addition, conditions such as pseudo- or hypermuscular obesity and sarcopenia, which are often observed in various endocrine diseases, were investigated in detail by using such methods. During weight loss, some of these methods were quite accurate in measuring changes in fat and lean mass. Apart from anthropometric measurements, a BC measurement if possible should be included in obesity assessment. Measurements of skin fold thickness combined with BIA are quite sufficient for routine clinical practice. However, in specialized clinics and in research, more sophisticated methods like ADP or DEXA are used.     

Body composition of elite American athletes

Five hundred twenty-eight male athletes participating in 26 Olympic events and 298 female athletes participating in 15 Olympic events underwent determination of body fat percentage (% fat) and lean body mass (LBM) via hydrostatic weighing and/or anthropometric methods. All groups of athletes were below the average values for % fat of college age men and women of 15% and 25%, respectively. In general, athletes involved in a sport where their body weight is supported, such as canoe and kayak (males, 13.0 +/- 2.5%; females, 22.2 +/- 4.6%) and swimming (males, 12.4 +/- 3.7%; females 19.5 +/- 2.8%), tended to have higher % fat values. Athletes involved in sports where a weight class has to be made to compete, such as boxing (males, 6.9 +/- 1.6%) and wrestling (male, Junior World Freestyle 7.9 +/- 2.7%), events such as the 100, 200, and 400 meters in athletes (male 100 and 200 meters, 6.5 +/- 1.2%; female 100, 200 and 400 meters, 13.7 +/- 3.6%) that are very anaerobic in nature and extremely aerobic events such as the marathon (males, 6.4 +/- 1.3%) demonstrated lower % fat values. Athletes involved in sports where body size is a definite advantage, such as basketball (males, 84.1 +/- 6.2 kg; females, 55.3 +/- 4.9 kg) and volleyball (males, 75.0 +/- 6.6 kg; females, 58.4 +/- 4.5 kg) tended to have a larger LBM.     

Body composition analysis by bioelectrical impedance: effect of skin temperature

Bioelectrical impedance analysis (BIA) was used to estimate body water and composition under both cool (14.4 degrees C, dry bulb) and warm (35.0 degrees C) ambient conditions in eight healthy adult men. The prediction equation provided with the commercially available instrument (RJL Systems) was used with the BIA measurements to estimate body composition. Skin temperature increased from 24.1 +/- 1.81 degrees C in the cool condition to 33.4 +/- 1.36 degrees C in the warm condition. (Mean increase was 9.3 +/- 1.75 degrees C, t = 15.05, P less than 0.01). The corresponding BIA resistances were 461 +/- 48 omega and 426 +/- 47 omega, respectively. (Mean reduction was 35.0 +/- 9.8 omega, t = 10.13, P less than 0.01). This resulted in a significant increase in predicted total body water (cool 47.4 +/- 5.5 l vs. warm 49.9 +/- 5.6 l, t = 3.88, P less than 0.01). Consequently, predicted fat mass was significantly lower in the warm than in the cool condition (8.8 +/- 3.2 kg vs. 11.0 +/- 3.7 kg; mean difference 2.23 +/- 0.69 kg, t = 9.22, P less than 0.01). These findings indicate that varying skin temperature by altering ambient temperature significantly changes resistance measurements and the estimation of total body water and percent fat by BIA. The observed changes in resistance are consistent with an apparent expansion of conductor volume in the warm environment and a reduction in the cooler condition. In this regard, the temperature-induced change in resistance could be due to alterations in cutaneous blood flow and/or compartmental distribution of body water. Thus, BIA measurements should be taken only under well-standardized ambient conditions.