Vastus lateralis and medialis muscular activation during frontal and sagittal single-leg jumps in sportswomen

Introduction: Differences in the lateral and medial portions from quiadriceps muscular activation during the jump execution can become a neuromuscular risk factor raising knee dynamic valgus, raising the risk for ACL injury. Objective: To determine the lateral and medial vastus difference activation using surface electromyography during single-leg jump in the sagittal and frontal plane in women athletes. Materials and methods: quantitative, cross-sectional study. A 64 female athletes study participation, testing antropometric mesures, vertical and lateral single-leg jump tests with the evaluation of vastus medialis and lateral electromyographic activation during the tests, and iliotibial band flexibility assessment. Results: it was found statistically significant relationship (p <= 0.05) between body mass index, fat percentage and vertical single-leg jumps power. Statistical significance was found (p <= 0.05), with greater activation of the lateral vastus in the right lower limb vertical jump and in the lateral jump in both lower limbs. Conclusion: Athletes presented differences in quadriceps activation, being higher lateral vastus activation in most of unipodal jumps, both in the sagittal and frontal plane; this may increase the risk for suffering knee injuries in sport practice.