The effects of augmented feedback on knee valgus angles and muscle activity during a jump landing task

Objective: To investigate effects of augmented feedback on knee valgus angles and hip muscle activity. Design: Repeated measures pre-test – post-test design to determine the effects of augmented feedback on knee kinematics and muscle activity. Setting: Research Laboratory Subjects: 32 healthy, recreationally active females (age= 20.3±1.3 yrs, height= 166.5±7.4cm, mass= 66.6± 12.4 kg) displaying visual knee valgus. Intervention: Intervention subjects were given video and verbal feedback regarding their landing technique. Statistical Analysis: Mixed model repeated measures ANOVA comparing control and intervention groups, and pre-test versus post-test; correlational analysis. Main Outcome Measure(s): Knee valgus angles; EMG amplitude of gluteus medius, gluteus maximus, hip adductors during a jump landing. Results: Significant differences in knee valgus angles were observed post intervention; however, muscle amplitude did decrease during the landing phase. Significance: Augmented feedback can alter kinematics and muscle activity however, more research is needed. Key Words: Augmented feedback, knee valgus, muscle activity, jump landin