Interscholastic Athletics and Bone Strength: The Iowa Bone Development Study.

ABSTRACT: Pashkova, A, Hartman, JM, Letuchy, EM, and Janz, KF. Interscholastic athletics and bone strength: the Iowa bone development study. J Strength Cond Res 36(5): 1271-1276, 2022-The objective of this study was to determine the relationship between adolescents' participation in various interscholastic sports and differences in bone strength outcomes. Subjects (N = 380) were recruited from the Iowa Bone Development Study and categorized based on sport participation into 3 power groups: no-power, low-power, and high-power. Sports such as basketball, cheerleading/poms, gymnastics, volleyball, track, football, tennis, and soccer were considered high-power. Peripheral quantitative computed tomography (pQCT) was used to determine bone measures of polar stress-strain index (measure of torsion strength), cortical content (measure of cortical bone size and area at the 66% tibia site), and bone strength index (measure of compression strength based on total bone density and area at the 4% tibia site). Adjusted pairwise comparison for group least squares means high-power sport participation compared with no-power sport participation showed significant differences in all bone strength outcomes for both men and women (p value < 0.01). There was a significant difference in all bone strength measures between low-power and no-power groups for men (p value < 0.05), but not women. Because of decreasing levels of physical activity in late adolescence, the promotion of high-power sports may be particularly important for optimal bone development in the final years before peak bone mass.