Effects of different sports on bone density and muscle mass in highly trained athletes

Purpose: It is known that participating in sports can have a beneficial eff ect on bone mass. However, it is not well established which sport is more b eneficial for increased bone mineral density (BMD) and appendicular muscle mass (AMM). This study investigated the effects of different high-intensity activities on BMD and AMM in highly trained athletes. Materials and Method s: Sixty-two male subjects aged 18-25 yr participated in the study. The sam ple included judo (J; N = 21), karate (K; N = 14), and water polo (W; N = 2 4) athletes who all competed at national and international level. Twelve ag e-matched nonathletic individuals served as the control group (C). All athl etes exercised regularly for at least 3 h.d(-1), 6 d.wk(-1). Segmental, tot al BMD, and AMM were measured with a dual-energy x-ray (DXA) absorptiometry (Lunar Corp., Madison, Wi). DXA analysis also includes bone mineral conten t (BMC) and far and lean masses. Results: Total BMDC, was significantly low er (mean +/- SD: 1.27 +/- 0.06 g.cm(-2), P < 0.05) than either judo or kara te athletes (total BMDJ (1.4 <plus/minus> 0.06 g.cm(-2)) and total BMDK (1. 36 +/- 0.08 g.cm(-2))) but not different from the W athletes (total BMDW (1 .31 +/- 0.09 g.cm(-2))). AMM was significantly lower in the C group compare d with the three athletic groups (P < 0.05). Fat mass was higher in the W v ersus J and K athletes but not different from the C group (P < 0.05). Concl usions: This cross-sectional study has shown that athletes, especially thos e engaged in high-impact sports, have significantly higher total BMD and AM M than controls. These results suggest that the type of sport activity may be an important factor in achieving a high peak bone mass and reducing oste oporosis risk.