Which muscle eccentrically decelerates hip adduction and internal rotation?

The gluteus medius, particularly its posterior fibers, plays a critical role in eccentrically decelerating hip adduction and internal rotation during movements. This muscle is primarily responsible for stabilizing the pelvis during activities such as walking, running, or any dynamic limb movement where balance is essential.

When the hip begins to adduct or rotate internally, the posterior fibers of the gluteus medius engage eccentrically to control this movement, preventing excessive motion that could lead to injury or instability. By gradually lengthening under tension, these fibers help stabilize the hip joint and maintain proper alignment of the lower extremity.

In contrast, while the other muscles mentioned also contribute to hip stability, they do not specialize in eccentrically decelerating hip adduction and internal rotation to the same extent as the gluteus medius (posterior fibers). The gluteus minimus assists with abduction and internal rotation but is not primarily focused on decelerating these movements. The tensor fasciae latae assists with hip flexion and abduction and can contribute to internal rotation but lacks the same capacity for deceleration in this context. The piriformis primarily functions in external rotation of the hip and does not play a significant role in the