Clam exercise for Runner’s Knee (patellofemoral pain syndrome)
There are more exercises and stretches that can help improve knee issues associated Runner’s Knee (patellofemoral pain syndrome):
www.integrativepersonaltraining.com/runners-lab/runners-knee-patellofemoral-pain-syndrome/
The clam exercise is a great starting place for improving glute and deep hip rotator strength. These muscles are extremely important for stability in the hip which by way of the femur and pelvis, respectively, affects the knee and low back.
source