Longitudinal determinants of 12-month changes on bone health in adolescent male athletes

Summary: We identified the determinants of 12-month changes of areal bone mineral density (aBMD), hip geometry and trabecular bone score (TBS) in adolescent male athletes. Changes in region-specific lean mass and the type of sport are the most consistent determinants in this population. Purpose: This study aims to identify the determinants of 12-month changes of areal bone mineral density (aBMD), hip geometry and trabecular bone score (TBS) in adolescent male athletes. Methods: The sample was 104 adolescent males aged 12–14 years at baseline that were followed over 12 months: 39 swimmers, 37 footballers (or soccer players) and 28 cyclists. Dual-energy X-ray absorptiometry measured aBMD at the whole body, lumbar spine and dual hip. Hip geometry estimates at the femoral neck were measured using hip structural analysis. Lumbar spine texture was measured by TBS. Results: Multivariate regression models significantly explained 38–60% of the variance in the aBMD changes, 36–62% in the hip geometry estimates changes and 45% in the TBS changes. Δregion-specific lean mass was the most consistent predictor of changes in aBMD outcomes (β = 0.591 to 0.696), followed by cycling participation (β = − 0.233 to − 0.262), swimming participation (β = − 0.315 to − 0.336) and ΔMVPA (β = 0.165). Cycling participation was the most consistent predictor of changes in hip geometry estimates (β = − 0.174 to − 0.268), followed by Δregion-specific lean mass (β = 0.587) and Δcardiorespiratory fitness (β = 0.253). Finally, cycling and swimming participation (β = − 0.347 to − 0.453), Δregion-specific lean mass (β = 0.848) and Δstature (β = 0.720) were predictors of change in TBS. Conclusions: Changes in region-specific lean mass and the type of sport are the most consistent determinants of 12-month changes in aBMD, hip geometry estimates and TBS in adolescent male athletes. Trial registration: ISRCTN17982776