Physical activity is associated with bone geometry of premenarcheal girls in a dose-dependent manner

Objective To determine the relationship between habitual physical activity (PA) level and peripheral qualitative computed tomography-determined quantitative tibia characteristics of premenarcheal girls. Methods Premenarcheal girls matched for age (10-13 years), bone age and maturity level were assigned into: a) low PA group (LPA, n = 25), b) moderate PA group (MPA, n = 17), and c) high PA group (HPA, n = 18). Participants' daily dietary intake, tibia's geometry and serum levels of calcium and vitamin D were assessed. Results Premenarcheal girls demonstrating HPA exhibited greater pericortical thickness, cross-sectional area (CSA) and bone mineral content (BMC) (p