Body composition in Karate: a dual-energy X-ray absorptiometry study

Karate is a widely practiced combat sport. Karatekas' body composition has typically been obtained in small groups using skinfolds or bioelectric impedance. In this work, we assessed three-compartment body composition using the accurate dual-energy X-ray absorptiometry technique (QDR Horizon, Hologic) in a large sample (n = 58; 74% males) of black belt karatekas. Stature-adjusted body composition indices (fat mass index; fat-free mass index; bone mineral apparent density) were calculated. The Student's t-test was used for group-group analysis. Correlation was assessed using the Pearson's r. The ability of fat-free soft tissue mass to predict bone mineral content and areal bone mineral density was assessed with linear regression. Reference mean and quartile values for whole-body and regional body composition were obtained for the male athletes. The body composition indices were generally more favorable in the male than female karatekas. The bone mineral apparent density was similar in the males and females at all sites except the right leg. The fat-free soft tissue mass predicted the bone mineral content and areal bone mineral density with good accuracy (R-2 = 0.542-0.827; p < 0.001 for all models). The data presented in this paper are expected to be of use for karate coaches, physical trainers, and participants interested in assessing and monitoring athletes' body composition.