The Effect of Six-Week Specific Injury Prevention Exercises on Performance in Female Volleyball Athletes with Neuromuscular Knee Valgus Defect: Quasi-Experimental Study

The key skills of volleyball require balance, agility, speed, and power in addition to core stability. Most volleyball injuries occur in the lower extremity during skilled performance. One of the reliable protocols in preventing sport injury and enhancing the performance is the “specific volleyball injury prevention exercise intervention”. In this study, the possible effect of the exercise intervention on core stability, balance, agility, speed, and power in female volleyball players with dynamic knee valgus (DKV) defect was investigated.

This quasi-experimental study included 30 female volleyball players. The assessments included double-leg squat (DLS) test, McGill core stability test, Y-Balance Test (YBT), 20-yard speed test, vertical jump test, and agility T-test. The training group participated in six weeks of the “injury prevention exercise intervention” and the control group participated in their usual routine at the same time. Analysis of covariance (ANCOVA) test was employed to analyze data in a significance level of α = 0.05.

The findings revealed significant improvement in core stability by 12.6% or 5.39 seconds (P = 0.01), speed by 1.64% or 0.07 seconds (P = 0.03), power by 11.84% or 3.6 cm (P = 0.01), and agility by 3.97% from 11.32 to 10.87 seconds, (P = 0.01) in the training group after 6 weeks of exercise intervention in comparison to control group. While the 3.68% increase in the balance record (76.3 cm) in the training group was not statistically significant (P = 0.11). The control group did not show significant change (P = 0.05). All the parameters improved significantly post-intervention in training group compared to pre-test measures (P ≤ 0.02).

Some athletes believed that valid injury prevention exercise interventions have negative impact on performance and they do not use these interventions. However, the findings of the present study showed that six weeks of exercise intervention significantly improved the core stability, speed, agility and power of female volleyball athletes with dynamic knee valgus. Therefore, performing this training intervention is recommended for female volleyball athletes with dynamic knee valgus defects and their coaches