The Effect of a 3-Week Neuromuscular Training Program and Its Retention on the Movement Pattern of Drop Vertical Jump in Active Girls with Knee Valgus

Abstract

Dynamic knee valgus during deceleration and drop landing in sport activities can be the cause of many acute and chronic knee injuries in female athletes. This study examined the effect of 3 weeks of neuromuscular training and its retention after 3 months on the movement pattern of drop vertical jump in 15-18-year-old active girls with dynamic knee valgus. Volunteers were screened by double legged squat test and finally, 24 subjects with dynamic knee valgus (12 subjects in the training group and 12 subjects in the control group) were selected as the sample. Knee valgus and flexion angles were calculated using two dimensional evaluation method with two video cameras (CASIO-Ex-F1, made in Japan) before and immediately after the training program in both groups and knee valgus angle was again calculated 3 months later during drop vertical jump test. Repeated measures was used to compare knee valgus and flexion angles before and immediately after and 3 months after the training intervention in control and training groups. In case of significance, independent and dependent t tests were used to recognize within- and between-group differences. The results showed that knee valgus angle mean decreased after training in the training group and this difference was significant (P=0.001). Also, knee flexion angle mean in the training group increased significantly (P=0.04). The results of paired sample t test showed a significant increase in this variable after the training and 3 months later in knee valgus angle in the training group (P=0.05). Results showed that although a 3-week neuromuscular training intervention improved movement pattern of drop vertical jump in active female students, the retention of the effect of this training decreased after 3 months.