Will continuing to run make my knees wear out faster?

Q: I'm 68 and I've jogged regularly for decades, but I've developed a touch of arthritis in my knees. Will continuing to run make my knees wear out faster?

A: Having mild arthritis in the knees should not stop you from running, and running probably did not create the problem in the first place.

The knees absorb a lot of force when running, so many people think that running itself can accelerate the natural wear and tear on the joints. But in fact, the medical research tends to show that running has a protective effect against arthritis. Studies of large numbers of men show that recreational runners have a lower risk of hip and knee arthritis. This effect is partly explained by the lower body weight of these men. Other studies that measure knee cartilage suggest that running may stimulate cartilage to grow, not wear it out.

But what should you do once arthritis appears? Keeping physically active and maintaining quadriceps (thigh) muscle strength are important, and running can help you with both. Softer running surfaces, like a track at a local school or a flat and smooth dirt trail, might be a little easier on your body.

If you are developing pain with running, it is helpful to vary your exercise routine and include some lower-impact exercise. Swimming and cycling are two excellent choices. The most important thing is to maintain a healthy weight and get regular aerobic exercise.

For more advice on living with and managing arthritis, buy Osteoarthritis, a Special Health Report from Harvard Medical School.