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Updated: Aug 16, 2025

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Effect of external isometric hip rotation force on lower extremity muscles activities during pelvic drop with
Roghayeh Jalil Piran1, Farideh Babakhani2, Ramin Balouchi1
1Department of Sports Injury and Corrective Exercise, Faculty of Physical Education, Allameh Tabataba'i University, Tehran, Iran.
Abstract:
Gluteus medius muscle (Gmed) dysfunction has been confirmed as a functional defect in subjects with Genu Valgum Deformity (GVD). The purpose of this study was to determine whether the change in the positions of hip rotation and applying isometric hip external rotation during pelvic drop (PD) can affect muscles activity in subjects with GVD. A total of thirty recreational female athletes with (n = 15) and without (n = 15) GVD participated in this study. Surface electromyography measured Gmed, tensor fascia latae (TFL), and quadratus lumborum (QL) muscles activity when subjects performed PD in three different positions of hip rotations with and without applied isometric hip external rotation force. There were differences in muscle activity between GVD and healthy subjects. The Gmed/TFL and Gmed/QL muscles activity ratio altered while placing the hip in different rotation positions and applying isometric load. The lower extremity muscles' activity is affected by GVD, and changing the positions of the hip rotation in the PD task can be associated with altered muscle activity in both GVD and healthy Groups. However, applying isometric hip external rotation during PD can be suggested as an effective intervention to increase Gmed activity.
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