Knee-Safe Aerobics

Low-impact aerobic exercise benefits those with knee problems by toning the muscles of the leg that support the knee joint - the muscles that help absorb shock before it reaches the knee joint. Aerobic exercises also help in weight reduction. Losing weight reduces stress on the knee joint - the impact placed upon on the knees is three times the body weight while walking. Aerobics also stimulate your the body to release endorphins - natural painkillers produced by one's own body.

Aerobic exercise is important for the health of the heart, lungs, and overall function of the body. However, high-impact exercises place extreme stress on the weight bearing joints. Those with knee problems should avoid high impact exercises. If you want to prevent future knee problems and knee pain you may want to replace high-impact activities with low-impact ones.

Warm up before aerobic exercise to slowly increase your heart rate and breathing rate and warm up the muscles. Do five minutes of slow paced walking or five minutes of the activity you are about to perform is. Cool down in the same manner. Cooling down is just as important as warming up. Be sure to stretch the muscles in your legs afterward (See stretches on knee exercises page.

Know when to stop. Once your muscles are fatigued, they can't absorb as much shock, and the extra stress is offloaded to the joints, tendons, and ligaments.

During pregnancy, hormones that allow the pelvic bones to become more flexible also cause the ligaments in the rest of the body to loosen. This increases the chance of injury to the joints, especially during high-impact exercises. Check with your doctor or physical therapist (physiotherapist) as to the safety of an exercise.

Recommended Low-Impact Aerobic Exercises

If you are experiencing knee pain, ask your doctor or physical therapist what exercises are appropriate.


Be sure to have proper shoes with adequate cushioning and support. Walk on even surfaces. Start with about 5 minutes of slower paced walking to warm up. Walk at a medium pace for about another 10 minutes per day and gradually build up to 30 - 60 minutes by adding a few minutes each time you walk. End your walk with 5 minutes of slower paced walking. After you get into better shape you can start walking at a faster pace to increase the intensity of your walks. You can increase the intensity level even more by swinging your arms as you walk. You should be about to talk while you are walking, otherwise you may be overexerting yourself.

Swimming and Water Exercises:

If you have access to a swimming pool, swimming is an excellent no-impact exercise. Regular 'land' exercises can also be done underwater. The buoyancy of the water supports most of the body's weight while the resistance of the water makes your muscles work harder to perform movements. You can use dumbbells and weights strapped to the ankles to intensify the workout without stressing the knees and other weight-bearing joints.

Overweight people in particular may find that walking aggravates knee pain. Walking underwater makes it possible for those with knee pain to get a good aerobic without stressing the joints. Most public swimming pools offer water exercise classes.

Many public pools offer water exercise classes specifically geared to people with arthritis. The water is usually between waist-deep to chest-deep so one doesnt have to know how to swim. Click here for warm water therapy.

Stationary bikes:

Make sure your seat is high enough so that your knees are not bent beyond a 90-degree angle. Your knee should be slightly bent when your pedal is furthest away. An upright stationary bike (looks like a regular bike) gives you a higher intensity work out than a recumbent bike. A recumbent bike reclines and usually offers bucket seats and cushioned back support. It may lesson the strain on your knees and lower back.

Elliptical Trainer:

Exercising on an elliptical trainer is lower impact than walking but can provide a higher intensity cardio workout. The elliptical trainer is a cross between a stair climber and stationary bicycle. It is designed to use all of the body's main muscle groups and is a great way to get into shape and lose weight without sacrificing your knees.

See Knee Exercises Page for exercises to improve knee stability.


Proper Footwear helps absorb shock and provides support. Even with low-impact exercises, proper shoes are important.

Drink lots of water to prevent dehydration, drinking 2 cups of water before you start, and 1 cup for each 15 minutes of aerobic exercise.