Upper and lower limb bone mass accrual in adolescent footballers across a short period of training and competition

Abstract

Objectives: To analyze bone mineral content (BMC) and area bone mineral density (aBMD) accrual in adolescent male footballers who started their first football season. Methods: 17 athletes (14.8 ± 0.4 years) were monitored across 15 weeks of football training. Participants were evaluated for somatic maturation (HPHV), BMC, and aBMD at three time points: before (M1) and after (M2) a preparatory phase, and at the end of the competitive phase (M3). BMC and aBMD were measured using DXA scans. Participants were divided into groups according to maturation status (circa-PHV and post-PHV), and the amount of accumulated training load (median split). Results: A significant effect (12.1 g/week, standard error (SE) = 2.6 g/week) was observed for lower limbs BMC across the three time points. There were no significant effects of time for upper limbs BMC. There was a significant effect of time for total body aBMD (0.007, SE = 0.003 g/cm2/week) across the three time points. Adolescents at post-PHV had a significant 245.6 g (SE = 56.1 g) higher BMC compared to adolescents at circa-PHV. No significant effects were observed for the accumulated training load. Conclusion: Systematic football training, even during the growth spurt, has a positive impact on adolescent bone markers despite the accumulated training load and maturation.