Relationships Between Vertical Jump and Composite Indices of Femoral Neck Strength in a Group of Young Women.

The purpose of this study was to investigate the relationships between vertical jump and composite indices of femoral neck strength (Compression strength index (CSI), bending strength index (BSI) and impact strength index (ISI)) in a group of young women. 206 young women (18 to 35 years) voluntarily participated in this study. Weight and height were measured, and body mass index (BMI) was calculated. Body composition, bone mineral content (BMC), bone mineral density (BMD) and trabecular bone score (TBS) were determined for each individual by Dual-energy X-ray absorptiometry (DXA). Composite indices of femoral neck strength (CSI, BSI and ISI) were calculated. Vertical jump was evaluated using a validated field test (Sargent test), and maximum power (P max, in watts) of the lower limbs was calculated accordingly. Vertical jump was positively correlated to CSI (r = 0.36; p < 0.001), BSI (r = 0.30; p < 0.001) and ISI (r = 0.33; p < 0.001). After adjusting for weight, vertical jump remained positively correlated to CSI (p = 0.026). The correlations between vertical jump and bone variables disappeared after adjusting for fat mass. The current study suggests that vertical jump is a positive determinant of composite indices of femoral neck strength in young women.