When the weather is lousy or the pollen count is high, it’s time to take your aerobic workout indoors. The treadmill and the elliptical trainer are two of the most popular cardio machines, but choosing which one is best can be a daunting task. This is especially true for those with arthritic knees.

Both the treadmill and the elliptical trainer simulate a natural walking or running motion. On a treadmill, you run in place while a belt moves under you. On an elliptical trainer, each foot is placed on a platform that you move in an oval-shaped motion. There are pros and cons to both machines. The best way to choose is by testing each machine and listening to how your body responds.

How Exercise Benefits OA

Osteoarthritis (OA) affects approximately 27 million Americans. There’s strong evidence indicating that moderate exercise, such as walking or elliptical training, provides numerous benefits without worsening symptoms or causing disease progression. According to a report from the U.S. Department of Health and Human Services, adults with OA can expect significant improvements in pain, physical function, quality of life, and mental health by engaging in low-impact physical activity for approximately 150 minutes per week.

A recent study found that people who did light exercise more than three days a week for less than two hours per day had much healthier knee cartilage than those who didn’t exercise at all. A low-impact cardio workout can benefit arthritic knees in the following ways:

Treadmills: Pros and Cons

If you’re jogging or running, a treadmill can put more stress on your knees compared to an elliptical trainer. But walking on a treadmill exerts about the same amount of force on the knees as using an elliptical machine. Treadmills tend to be more user-friendly and easier to use for beginners. They may also be better for building bone density.

Problems can occur when you’re ready to ramp up the intensity of your workout. When you increase the treadmill’s speed, you run the risk of putting more pressure on your knees, thereby increasing your pain and risk of tendonitis or bursitis.

Safety Tips: If you’ve never used a treadmill, ask an exercise specialist or trainer for a demonstration or assistance. Before stepping on the machine, make sure you know where the on/off switch is, how to work the controls, and how to use the emergency shut-off clip or key. Never step on or off the belt while it’s moving, and wear shoes that are appropriate for aerobic exercise. If the treadmill has an incline function, consider slightly raising the grade. Research suggests that a 3 percent incline grade can reduce shock on the legs and knees by 24 percent. Any more than 3 percent incline grade can have the reverse effect and increase stress on the joints.

Elliptical Trainers: Pros and Cons

Using an elliptical machine is like combining stair-stepping with cross-country skiing. Instead of using a natural walking motion with the heel of the foot repeatedly striking the treadmill belt, each foot rests on a platform and moves in an oval, or elliptical, motion. This zero impact movement allows you to increase the intensity of your workout without increasing the stress on your joints. Some elliptical machines are equipped with handles that move in conjunction with the lower body. This works out the arms, chest, and shoulders and causes the body to burn more calories. Also, most elliptical machines allow you to pedal in reverse, which strengthens different muscle groups in the lower legs.

For beginners, elliptical trainers tend to have a steeper learning curve and can be awkward to use. They also don’t offer the same bone-strengthening benefits of treadmills. Overdoing it on an elliptical trainer can cause bursitis in the hip, so those with a history of hip problems may want to opt for the treadmill instead.

Safety Tips: Because the elliptical trainer can be more difficult to use than a treadmill, it’s even more important to get a demonstration and learn the controls before stepping onto one. If you’re new to elliptical trainers, you may want to avoid the moving handles at first. Most machines have a set of stationary handles that are easier to use. And if you have a choice, opt for machines with wider foot platforms. These machines will allow you to adjust your stance for better balance and less pressure on your joints.

The Verdict

When used correctly, both the treadmill and the elliptical trainer can be safe, effective workout options for those with OA of the knee. Depending on your specific needs and skill level, one may suit you better than the other. If you’re new to workout machines or are at a higher risk of OA, the treadmill can be a user-friendly way to safely exercise and promote bone health. As you progress into your workout program and begin to increase the intensity of your exercise, the elliptical trainer can allow you to do so without increasing the stress placed on your knees.

Most importantly, listen to your body. If you experience knee pain or discomfort on one machine, simply try the other. If both options make you uncomfortable, try other low-impact exercise options such as a stationary bike or water aerobics.

Regardless of what exercise equipment you are using, always check with your physician before using. When arthritis is severe, a treadmill may be too difficult or dangerous to use and maybe too painful for the patient. Riding a recumbent bicycle is another option that can strengthen the quadriceps and hamstring muscles, which are extremely important when going from the sitting to the standing position.

Remember, the worst thing you can do for your arthritic knees is to quit exercising altogether. Always talk with your healthcare provider before you start a new workout program to learn what’s appropriate for your needs.