The Effects of Instruction Exercises on Performance and Kinetic Factors Associated With Lower-Extremity Injury in Landing After Volleyball Blocks.

Context: Female volleyball players are more predisposed to anterior cruciate ligament injury in comparison with their male counterparts. Recent research on anterior cruciate ligament injury prevention strategies has shown the positive results of adopting the external focus (EF) of attention in sports. Objective: To determine the effect of 6-week EF instruction exercises on performance and kinetic factors associated with lower-extremity injury in landing after the volleyball blocks of female athletes. Design: Pretest and posttest control study. Setting: University research laboratory. Participants: Thirty-two female volleyball players (18-24 y old) from the same team randomly divided into experimental (n = 16) and control (n = 16) groups. Intervention: The experimental group performed a 6-week exercise program with EF instructions. The control group continued its regular volleyball team schedule. Main Outcome Measures: To assess function, single-leg triple hop test for distance was used. A force plate was used to evaluate kinetic variables including vertical ground reaction forces, the rate of loading, and dynamic postural stability index. All data were assessed at baseline and after the intervention.
Results: There was a significant increase in single-leg triple hop test (P < .05) and in the first and second peak ground reaction force, rate of loadings, dynamic postural stability index (P < .05).
Conclusion: According to the results of this study, anterior cruciate ligament injury prevention programs should incorporate EF instruction exercises to enhance the kinetics and to increase athletes' functional performance.

RCT Entities:   Population Interventions Outcomes