During loading response, the internal muscle action at the hip is primarily what?

During loading response, the internal muscle action at the hip is primarily what?

• A. Eccentric dorsiflexors
• B. Isometric/concentric hip extensors
• C. Eccentric hip flexors
• D. Concentric quadriceps only

Answer: (B)

During loading response, the leg needs to accept weight while keeping the pelvis and trunk stable. The hip extensors do the main work at the hip by holding the hip in place (isometric action) and then, as weight acceptance continues, producing hip extension (concentric action) to help move the body forward into midstance. This combination helps control the position of the thigh and maintain alignment as the limb bears weight. The other options don’t fit: the dorsiflexors act at the ankle, not the hip; hip flexors would shorten the hip (not stabilize/extend) during this phase; and the quadriceps action described as concentric only relates to the knee, not the hip.

During loading response, the leg needs to accept weight while keeping the pelvis and trunk stable. The hip extensors do the main work at the hip by holding the hip in place (isometric action) and then, as weight acceptance continues, producing hip extension (concentric action) to help move the body forward into midstance. This combination helps control the position of the thigh and maintain alignment as the limb bears weight. The other options don’t fit: the dorsiflexors act at the ankle, not the hip; hip flexors would shorten the hip (not stabilize/extend) during this phase; and the quadriceps action described as concentric only relates to the knee, not the hip.