Relationship Between Single-Leg Countermovement Jump Height, Technique, and Hip Strength in Elite Handball Players

Single-leg jumping is a fundamental movement in sports and is frequently used for performance assessment and injury risk evaluation. However, the specific kinetic and kinematic factors influencing jump performance remain unclear. This study aimed to examine the relationships between sagittal and frontal plane kinematic variables, maximal and explosive isometric hip strength, and single-leg countermovement jump (SLCMJ) performance. We assessed eighty elite handball players who performed SLCMJs on force plates, with jumps being video recorded from both the sagittal and frontal planes. Maximal and explosive hip adduction, abduction, extension, and flexion strength were assessed using an isometric dynamometer. Correlation analysis revealed significant relationships (p < 0.05) between maximal hip abductor strength and sagittal plane hip flexion angle (r = -0.23), femur inclination (r = -0.27), and shin inclination (r = 0.23). Explosive adduction strength was significantly correlated (p < 0.05) with frontal plane trunk angle (r = -0.29) and trunk inclination (r = -0.33). A significant negative correlation (p < 0.05) was also observed between femur inclination and jump height (r = -0.30). However, no significant relationship (p > 0.05) was found between hip strength variables and jump height. These findings suggest that while isometric hip strength influences movement kinematics during SLCMJs, its direct impact on jump height is limited. Based on the results of the present study, other factors likely contribute to jump performance outcomes and should be investigated further.