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Background and Objective: Anterior cruciate ligament (ACL) injury is one of the most serious knee injuries and it happens frequently during sports activities. Appropriate muscle activity is essential to provide joint stability and prevention of ACL injury. This study was performed to determine the effect of external focus instructions and functional training on basketball knee stabilization muscle activity timing.
Methods: This clinical trial study was performed on 48 healthy male basketball players of the Iranian Provincial League in the age range of 19-25 years. The basketball players were randomly divided into 3 groups of 16 people including control group, functional training group with feedback and group without feedback. The timing of the onset of electrical activity in the quadriceps, hamstrings, and Gluteus medius muscles of individuals before and after eight weeks in the single-leg landing task was examined by electromyography.
Results: There was a significant difference between the groups at the onset of Biceps Femoris, Gluteus Maximus, Gluteus Medius, Vastus Medialis, Vastus Lateralis, Rectus Femoris and Medial Hamstring muscles. There was a significant decrease in muscle activity onset between functional groups with and without feedback in compared to control group (P<0.05). There was no significant difference between the training groups at the beginning of the activity of the mentioned muscles.
Conclusion: Functional basketball training with and without feedback can optimize the activity time of the knee stabilizing muscles, during exercises such as jump-landing, increase the stability of the knee joint and possibly reduce ACL injury in athletes.