One of the most common musculoskeletal deviations that cause chronic pain is overpronation of the foot; this is when the foot flattens out and the weight collapses toward the inside of the body. Overpronation can cause the connective tissue that runs along the underside of the foot (i.e., plantar fascia) to become irritated and lose its ability to function correctly. Habitual overpronation can cause other structures in the body like the ankles, knees, and hips to take up the slack caused by the foot not working properly and can lead to overuse, pain, and imbalances in these parts of the body as well.  Justin Price, creator of The BioMechanics Method, explains in the video below how to do this exercise properly and why it is so important for anyone experiencing foot and ankle pain.