EXERCISE ESSENTIAL FOR ARTHRITIS OF THE KNEE

Report #6330 9/16/94

A recent report in the Journal of Orthopedic and Sports Physical Therapy shows that at least one of the principles taught in most exercise physiology classes is wrong.

Isometric strength training means to contract your muscles against an object that doesn't move, such as to push as hard as you can against a wall. Virtually all exercise physiology text books state that when you contract a muscle against something that doesn't move, you become strong only at the angle that you hold your joint.

Recent studies show that you certainly gain the most strength at the angle that you hold, but you also become strong throughout the full range of motion. These recent studies offer new treatment and hope for people with severe arthritis. The most important part of a rehabilitation program for people with damaged knees is to stabilize the knees by strengthening the muscles of the upper leg that control the knee. However, pain and swelling often prevent people with severe knee arthritis from exercising their knees at all. If they place a resistance that would not move against the front of their ankles and contract their quad muscles in the front of their upper legs very hard, they would not move their legs, but they still would strengthen their quad muscles throughout their full range of motion. A study in the Journal of Orthopedic and Sports Physical Therapy showed that these isometric exercises were very effective in rehabilitating people with severe osteoarthritis of their knees.

By Gabe Mirkin, M.D., for CBS Radio News