Sport-specific association between exercise loading and the density, geometry, and microstructure of weight-bearing bone in young adult men

Abstract

SummaryIn this population-based study of 24-year-old men, we have investigated the association between sport-specific exercise loading and different bone parameters. We reveal that the association between exercise loading and bone parameters is sport-specific, indicating that nonspecific resistance exercise does not impact bone density, geometry, or microstructure in young men.IntroductionIn this cross-sectional study, the association between nonspecific resistive exercise and areal and volumetric bone density, bone geometry, or bone microstructure was investigated in young adult men.MethodsA total of 184 male athletes, 24.0 ± 0.6 years of age (mean ± SD), representing nonspecific resistive exercise and soccer (proportion of recreational athletes, 93.4 and 7.7 %, respectively), and 177 nonathletic age-matched controls were measured with dual-energy X-ray absorptiometry. Radius and tibia were measured by peripheral quantitative computed tomography (pQCT) at the diaphysis and by three-dimensional pQCT at the metaphysis.ResultsMen in the nonspecific resistive exercise group had higher grip strength(9.1 % or 0.4 SD) and higher lean mass(5.6 % or 0.5 SD) than those in the nonathletic group(p < 0.01 and p < 0.001, respectively). However, men who participated in nonspecific resistive exercise did not have higher bone density or a more favorable bone microstructure or geometry than their nonathletic referents. In contrast, men playing soccer had higher areal bone mineral density (aBMD) at the femoral neck (19.5 % or 1.2 SD) and lumbar spine (12.6 % or 1.0 SD), as well as larger cortical cross-sectional area (16.4 % or 1.1 SD) and higher trabecular bone volume fraction (14.5 % or 0.9 SD), as a result of increased trabecular number (8.7 % or 0.6 SD) and thickness (5.7 % or 0.4 SD) at the tibia than men in the nonathletic group(p < 0.001).ConclusionsWeight-bearing exercise with impacts from varying directions (playing soccer) is associated with aBMD and volumetric BMD, cortical bone geometry, as well as trabecular microstructure of weight-bearing bone. Nonspecific recreational resistance exercise does not appear to be a strong determinant of bone density, geometry, or microstructure in young adult men.