Vertical Jump Power Is Associated with Healthy Bone Outcomes in Youth: ROC Analyses and Diagnostic Performance

Using a sample of healthy youth (n = 466, 10 to 18 yr), we report the predictive utility of vertical jump power (VJ Power, W) for predicting bone strength. We measured VJ Power using mechanography and an indicator of bone strength, i.e., height-adjusted total bone mineral content less head (TBLH BMC, g), using DXA. Growth curve models were used to convert VJ Power to age- and sex-specific percentiles/Z-scores. Associations were examined using receiver operator characteristic curve analysis, i.e., area-under-the-curve (AUC), as well as sensitivity (Se) and specificity (Sp) for Desirable, Marginal, and Low groups based on VJ Power percentiles. The AUC was 0.84 for TBLH BMC [less than or equal to] -2.0 Z-score from VJ Power percentiles. Se for Marginal and Low groups were 71.4% and 42.9%, respectively. Sp for Marginal and Low groups were 85.2% and 95.1%, respectively. The results suggest the utility of using VJ Power percentiles for assessing bone strength.