There should always be an active component to your rehab program which includes various types of therapeutic physical therapy exercises, not just passive modalities.Exercise increases muscle flexibility, mobility, and strength, as well as promoting healing by increasing blood flow to the injured site. Healthy muscles provide protection to bones and joints, keeping you safer and stronger in the future. Some soreness and tightness with exercise is expected, it’s a normal part of exercise to feel sore after working your muscles the right way.