Comparison of Different Angles of the Knee Joint on the Activation of Selected Hip Muscles in the Movement of the Supine Bridge

Changing the knee flexion angle and using unstable devices are some ways to change the activity of the hip and trunk extensors in supine bridge exercise. The present study intends to compare the effect of different knee flexion angles in bridge exercise at the unstable surface on the activation of selected muscles of young male soccer players.

Eighteen young players performed one-session bridge exercises on a Bosu ball on full-extension (0°), 45°, and 90° of knee flexion, and electromyography was used to assess the amount and the onset of activity in selected hip muscles.

The results showed a significant difference in the electrical activity of Semitendinosus, Biceps Femoris, Gluteus Maximus, and Gluteus Medius at different knee angles (P=0.001). Furthermore, Even the results showed a significant difference in the onset of Gluteus Medius muscle activity at different knee angles (P=0.005), but the difference was not significant in the onset of Semitendinosus muscles (P=0.52), Biceps Femoris (P=0.12) and Gluteus Maximus (P=0.40) at different knee angles.

For strengthening the Hamstrings, bridge exercise with less knee flexion angles and for reinforcing the Gluteal muscles, bridge exercise with more knee flexion angles showed more effectiveness. Additionally, results have shown that performing bridge exercises on Bosu Ball with 45° of knee flexion can activate the Gluteus Medius muscle faster. Therefore, based on the findings of this study, this exercise on different angles of the knee joint can be used for specific aims and by considering the individual needs.