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

Background. The purpose of the present study was to evaluate the difference s in the body composition estimate of highly trained male athletes by three different methods: dual-energy X-ray absorptiometry (DXA), bioelectrical i mpedance analysis (BW) and skinfold thickness measurement (SFT). Methods. The study occurred during a non-intensive training period. The mea surements were performed at the Human Physiology laboratory, Participants: forty-three male athletes (19 waterpolo, 9 judo, 15 karate) who exercised r egularly at least three hours per day, six days per week. Measurements: DXA , BLS. 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-may ANOVA, with p osthoc Bonferroni test when values mere significantly different. The same t est was used to compare FFM values, The coefficient of variation (CV%=100xS D/mean) was calculated for each methods, Methodological differences among t he various methods were analysed with the method of Bland-Altman. Results. ANOVA test showed significant differences among the three methods, Ln particular, DXA significantly (p<0.001) over-estimated %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 BW (9.9+/-1.4% and 69.4+/-7.9 kg), Also Bland-Altman comparis on among the estimates indicated nide differences between methods. Conclusions. DSA provides different body composition estimates than those d erived from skinfold thickness measurement and BIA, so that the methods sho uld not be used interchangeably.