Dear Sir,
There are multiple joint problems that can occur in the knee, and I applaud you for wanting to attempt to be proactive about treating it. The conservative approach would begin with gently stretching and non-weight bearing motion. This could occur for 5-10 minutes, but include both knees (an injury or discomfort on one side could cause you to place additional stress in the "good" side.) Progress to mild weight bearing motion such as low resistance stationary bicycle. Also helpful would be water exercises at your local health club or YMCA. Stretching in a hot tub or Jacuzzi is also beneficial.

Richard,

Knee problems are very common. The most likely cause as people age is arthritis, though problems with the menisci are not rare either. Together they make up what most people think of as ware and tare or what is called joint degeneration. Keeping knee joints healthy is a matter of many factors including: weight, activity levels, use patterns and previous injury. When rehabilitating knee problems a few things must be considered: First, that full range of motion (ROM) is available. A healthy knee should be able to straighten out fully and bend to at least 115 degrees to permit normal activity. Second, strengthen the knee extensors and flexors. These are primarily the quadriceps and the hamstrings. This can be done using many different exercises. Third, improve balance and stability. A good way to do this is to stand on one leg. This is sometimes easy, sometimes not. When starting out, hold for 10, 30 or 60 seconds and repeat several times during the day. Later, closing the eyes or moving the arms and trunk while balancing develops greater stability.

A stationary or road bike is great for general ROM, but would have to be used with real effort for strengthening, maybe even getting up from the seat to peddle in standing. Walking can be great exercise for the heart and lungs, but unless it is walking up and down steps or hills not much for the knees. Shoes or shoe inserts can be helpful for some types of knee pain. When the problem is pain due to too much force being taken by the knee a shock absorbent type might work best. Shoes and inserts are like pain relievers, you have to find the ones that work best for you.

Care should be taken to avoid painful activities that don’t represent normal muscle soreness from exercise. Avoid activities that cause swelling. Avoid twisting on the knee, sharp turns on a planted foot or cutting maneuvers. A book or internet site would discuss all the different ways to strengthen the knees. Red flags for knee problems include: persistent pain or swelling, deformities, limping, and blocks to ROM. If these develop, see your health care provider. Above all, be safe and listen to your body.