Hip flexors are concentrically active during which part of swing?

Hip flexors are concentrically active during which part of swing?

• A. First half of swing
• B. Entire swing phase
• C. Second half of swing only
• D. Terminal stance only

Answer: (A)

The main idea is that hip flexors produce hip flexion to move the thigh forward and clear the foot during the early part of the swing. In the first half of swing, these muscles shorten actively (concentrically) to advance the limb. After mid-swing, momentum and other muscle actions help continue the swing, while the body prepares for heel strike, and the hip is more often controlled eccentrically by hip extensors to slow and prep for contact. The terminal stance is a stance-phase portion, not swing, so it wouldn’t involve concentric hip flexion. So the hip flexors are concentrically active during the first half of swing.

The main idea is that hip flexors produce hip flexion to move the thigh forward and clear the foot during the early part of the swing. In the first half of swing, these muscles shorten actively (concentrically) to advance the limb. After mid-swing, momentum and other muscle actions help continue the swing, while the body prepares for heel strike, and the hip is more often controlled eccentrically by hip extensors to slow and prep for contact. The terminal stance is a stance-phase portion, not swing, so it wouldn’t involve concentric hip flexion. So the hip flexors are concentrically active during the first half of swing.