Hip Rotations' Influence of Electromyographic Activity of Gluteus Medius Muscle During Pelvic-Drop Exercise.

CONTEXT: Pelvic-drop exercises are often used to strengthen the gluteus medius (GM) muscle with the aim of increasing or prioritizing its recruitment. However, the effect of hip rotation on the performance of the action of the GM is unknown.

OBJECTIVE: To evaluate the effect of hip rotation on the recruitment of the GM, tensor fasciae latae (TFL), and quadratus lumborum (QL).

METHOD: Seventeen healthy subjects performed 2 sets of 4 repetitions of pelvic-drop exercise in random order with pelvic-drop lateral, medial, and neutral rotation of the hip.

MAIN OUTCOME MEASURES: The electromyographic (EMG) activity of the GM, TFL, and QL was evaluated using surface electromyography.

RESULTS: There were significant increases in the activation of the GM with medial and neutral rotation compared with lateral rotation (P = .03, P = .01, respectively), and there was no difference between medial and neutral rotation (P = 1.00). There was no difference in EMG activity of the TFL and QL in any of the positions. The GM:TFL ratio was the same in all analyzed positions. Regarding the GM:QL ratio, there was a significant increase with medial rotation compared with lateral rotation (P = .02).

CONCLUSIONS: Pelvic-drop exercises are more efficient for activating the GM when the hip is in medial rotation and neutral position.