Movements in Different Hip Joint Positions Affect Gluteus Maximus and Gluteus Medius Muscle Activities

[Purpose] The activities of the gluteus maximus and gluteus medius induced by different movements, and the hip extension and abduction torque values of different limb positions were investigated and compared. [Subjects and Methods] The subjects were 10 healthy male adults, and the muscles examined were the gluteus maximus (Gmax), gluteus medius (Gmed), biceps femoris, and the back muscles of the lumbar region. Hip extension and abduction were performed in the supine position in three limb positions of hip flexion of 0 and 90˚, and hip extension of 15˚. The values of hip extension and abduction torque were also measured during the movements. [Results] Gmax showed high values of muscle activity during extension with 15˚ hip extension, and during abduction with 90˚ hip flexion. No differences were found among the Gmed activity values. No differences were found in hip extension torque among the different limb positions, but abduction torque showed a high value at hip flexion of 0˚. [Conclusion] The anatomical characteristics of Gmax and Gmed were electromyographically corroborated.