Arthritis and exercise.

Exercise is medicine. It promotes health and can be instrumental in the treatment of chronic disease. Current knowledge suggests that exercise carried out within the limits of normal joint motion and comfort does not predispose to osteoarthritis. In fact, normal repetitive loading to a joint is essential for its physiologic function. Sports that subject joints to intermittent high or violent impact loads may increase the risk of subsequent osteoarthritis, but well-designed studies are lacking and this association is at best speculative. There is clear evidence, however, that joints with preexisting injury, particularly if there is biomechanical alteration, are at increased risk of developing osteoarthritis with repetitive loading. Finally, patients with arthritis can derive a number of benefits from a thoughtful and closely monitored exercise program.