Dr. Gaby Go, DPT, Run Coach on Instagram: "If you notice your legs crossing over when you run or see excessive knee valgus (knees caving inward) during single-leg exercises, a weak gluteus medius (glute med) is often a key factor. This muscle plays a crucial role in stabilizing the pelvis and controlling the position of the femur during weight-bearing activities like running and single-leg movements. When the glute med isn’t strong enough, the pelvis may drop, which causes the femur to rotate in