Association between pubertal timing and bone and body composition in young adult men

Bone and muscle development are important processes in pubertal maturation. The aim of this study was to investigate associations between pubertal timing and bone density and body composition in young adult men. In this observational study, bone and body composition was cross-sectionally assessed by dual-energy X-ray absorptiometry in 2056 healthy young men with median age 19, who retrospectively self-reported if they experienced pubertal changes at an earlier, similar or later age than their peers. Associations between voice break timing and bone and body composition were analyzed by linear regression. Men reporting earlier voice break than their peers (n = 417, 20%) had higher lumbar bone mineral density (BMD) and higher total body BMD. Apart from higher BMI, there were no differences in body composition. Men who reported later voice break (n = 353, 17%) had lower lumbar bone mineral content, bone area and volume, but similar BMD. They had lower BMI, lean mass and fat mass, resulting in a lower fat-to-muscle ratio. In conclusion, even after adult height has been reached, physiological variations in pubertal timing were associated with differences in bone and body composition in young adult men.