Flexibility can be limited by bone structure or by soft tissues such as the muscles and their fascial sheaths, the joint capsule, or the tendons. Soft tissue stretching can bring about significant changes in joint mobility. Besides being an important part of conditioning for sports participation, flexibility exercises are a necessary part of rehabilitation from injury. Prolonged stall rest or wearing a splint or cast results in shortening of the tissues around a joint. Trauma causes protective muscle splitting, which can result in muscle fiber shortening if allowed to persist.
Muscle strength is lost when soft tissue adaptively shortens over time.
The muscle is tight, yet functionally weak and no longer capable of strong or ballistic contraction. A more severe condition results when scar tissue is laid down between otherwise normal muscle fibers and ties down the motion and function of the muscle. Chronic inflammation in the muscle can cause fibrotic adhesions to form throughout the musculature, reducing its contractility and extensibility. Pain Relief Stretching exercises can be of great benefit in providing relief from pain arising from the muscles or the fascia. Fascial contracture occurs when muscles and their connective tissues tighten abnormally.