The purpose of the present investigation was to determine the validity of human body composition assessed by bioelectrical impedance analysis (BIA). The subjects were healthy Japanese adult men (n = 40) and women (n = 40). Equations from the study of Segal et al. (1985) and Lukaski et al. (1986) were utilized to estimate lean body mass and body density, respectively.
　Analysis of the data indicated that percent body fat and lean body mass estimated by BIA correlated highly with those assessed by underwater weighing ; i. s., r= 0.854 ~ 0.878 and r= 0.786 ~ 0.940, respectively. The magnitude of these correlations was higher than that obtained between skinfold thickness measurements and underwater weighing. However, the absolute value of percent body fat estimated by BIA was 30% smaller and that of lean body mass was 8% larger as compared with densitometrically determined respective value.
　We suggest that, while the correlations of body composition variables estimated by BIA with densitometrically determined variables are found considerably high even for the Japanese population, additional research needs to be done to develop population-specific equations.

DESCENTE SPORTS SCIENCE Vol.11/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE