Effectiveness of an Injury Prevention Program in Female Soccer Players

Abstract

PURPOSE: To assess the effectiveness of an injury prevention program incorporated as dynamic warm-up in soccer practice for female athletes. It was hypothesized that the intervention group would decrease knee valgus while increasing knee flexion during a 40-cm drop jump after participating for 6 weeks in an injury prevention program. METHODS: Four female soccer teams (n=73; age range 14-18) were randomized into a control (n = 27; height: 165 ± 9.6 cm; weight: 63 ± 17 kg) or intervention group (n = 46; height: 162 ± 6.6 cm; weight: 56 ± 5 kg). Dynamic knee valgus and knee flexion were assessed during a 40-cm drop jump at baseline and after 6-weeks using a 2-dimensional system. The intervention group performed an injury prevention program integrated as dynamic warm-up 2×/week for 6-weeks. The program consisted of 20 minutes of plyometrics, agility drills, lower extremity strengthening exercises, and flexibility for major lower extremity muscle groups prior to soccer practice. Comparisons at baseline were performed for anthropometric, dynamic knee valgus and knee flexion variables. Comparisons at baseline showed differences between groups for the variable of dynamic valgus. The variable of interest was the difference between post-intervention minus pre-intervention values. One-tailed independent samples t-tests were performed for the variables of dynamic knee valgus and knee flexion. RESULTS: All variables met parametric tests' assumptions. The group allocated to the injury prevention program significantly increased their knee flexion (3.20°) whilst the control group decreased their knee flexion (1.30°) during landing from the 40-cm drop jump (p = 0.05). The changes in dynamic knee valgus were minimal for both groups (<0.32 cm) and were not statistically significant between groups (p = 0.35). CONCLUSIONS: While an injury prevention program incorporated as dynamic warm-up into regular soccer practice in teams of female players help improve knee flexion during landing from a drop jump, it may be not sufficient to reduce other factors related to knee injury such as dynamic knee valgus.