Comparison of hip extensor muscle activity including the adductor magnus during three prone hip extension exercises.

OBJECTIVES: This study compared the role of the adductor magnus muscle (Amag) as a hip extensor while performing active prone hip extension (PHE), PHE with hip adduction (PHE-ADD), and PHE with hip abduction (PHE-ABD) with the gluteus maximus (Gmax) and hamstrings.

METHODS: The study recruited 22 healthy participants. Electromyography data were recorded from the Amag, Gmax, and medial and lateral hamstrings during PHE, PHE-ADD, and PHE-ABD. Normalized electromyographic data were examined using one-way, repeated-measures analyses of variance.

RESULTS: The magnitude of the Amag, Gmax, and hamstring activations did not differ significantly while performing PHE (p = 0.41). Furthermore, the Amag and hamstring activations were significantly greater than the Gmax activation when performing PHE-ADD (p < 0.05). The Gmax showed significantly greater activation during PHE-ABD than the Amag and medial and lateral hamstrings (p < 0.05).

CONCLUSIONS: Based on these results, we advocate including the Amag as a hip extensor during the PHE test or exercise. Our preliminary results have the potential to be applied directly to the PHE test, for investigating the muscle-activation pattern of the Amag with the Gmax and hamstrings in patients with hip or lower back pain.