If you have arthritis of the knees, exercise should still be a part of your lifestyle. The key is to know the right exercises and the right way to do them.

Generally, long-term exercise is safe for adults with knee pain. Moreover, when performed correctly, the right exercise can even decrease the pain of arthritis. This can improve your ability to carry out ordinary physical activities.

It may seem counter-intuitive for exercise to decrease knee pain, so it’s helpful to understand how it works.

Exercise brings blood and nutrients to the cartilage, making it more effective at protecting and guiding your joints during movement. Exercise also improves muscle strength. Stronger muscles are able to carry body weight more efficiently, relieving some of the burden put on the joints.

However, performing the “wrong” exercise or using poor form may increase pain or inflict damage on the joint. “Pain isn’t normal,” warns Alice Bell, a doctor of physical therapy and board-certified specialist in geriatrics.

A smart exercise routine can be easy to master. Although broad guidelines can be helpful, the safest and most effective way to launch into an exercise routine is with the guidance of a licensed professional, such as a physical therapist. An expert will analyze your form and make suggestions.

Keep reading to learn how to safely practice some of the more popular exercise options. We’ll also share a few low-impact alternatives that you can add to your workout regimen.

Squatting can help build up leg and hip strength, leading to more stable joints. Over time, your range of motion will increase. As long as you’re able to practice without feeling pain, it’s safe to include squats in your exercise routine.

People with arthritis may find the most benefit in wall squats, since squatting against the wall can help reduce your risk of putting unnecessary or incorrect pressure on your knees.

To do a basic squat:

  1. Stand with your back against a wall. Your feet should be shoulder-width apart, with your heels about 18 inches away from wall.
  2. Keep your knees in line with your heels, not out in front of your toes.
  3. Breathe in and exhale as you sit down or “squat.” Your buttocks shouldn’t drop any lower than knee level.
  4. Keep your abdominal muscles tight and ensure that your back is pressed flat against the wall.
  5. Push up through your heels — not the balls of your feet — and inhale as you stand up.

“Keep the knee over the ankle and not over the ball of the foot,” Bell cautions.

If you begin to experience intense pain at any point — more than your typical knee pain — you should stop the practice for the day. Be sure to give the move another try during your next practice. You’ll find that your pain threshold increases as you build up muscle strength.

For people with knee arthritis, lunging poses the same benefits and risks as deep squatting. Lunges are a great way to improve your overall leg and hip strength, but may cause unnecessary pain when practiced incorrectly.

The trick, Bell says, is to make sure your knee doesn’t extend past your ankle.

You may also find it helpful to practice lunges while holding on to the back of a chair or table for added support.

To do a basic lunge:

  1. Grab on to your support, if needed.
  2. Step forward with one leg. Be sure to keep your forward knee above your ankle. Your knee should never extend past your ankle.
  3. Once you’re stable in position, slowly lift your back heel off of the floor.
  4. Keep lifting until you form a straight line from your back knee to your hip.
  5. Engage, or tighten, your abdominal muscles. This will help keep your back straight as you move into a lunging position. Slouching or leaning forward will put unnecessary stress on your front knee.

During your practice, it’s important that you take note of any changes in pain or discomfort. If you begin experiencing more pain than usual, you should stop lunging for the day and move on to another form of exercise.

Running can increase your overall wellness and help control weight. This can reduce the amount of stress on your knees and lessen the overall impact of arthritis.

However, some caveats do apply:

  • Choose sturdy, supportive shoes. “Footwear is underrated when it comes to protecting your joints,” Bell says.
  • Run on dirt, grass, gravel, or asphalt, if available. They’re softer than concrete.
  • Pay attention to any pain. If you begin experiencing more pain than usual, take a break for a day or two. If the pain continues, see your doctor. An unusual pain may be the result of something other than arthritis.

Although people with knee arthritis can run safely, Bell advises leaving this sport to those who have been running for a while. She’s banking that long-time runners have developed proper running form and have developed muscle support around the joint.

“No one with arthritis should start running,” she says flatly.

If running hasn’t been a part of your exercise routine and you find that you’d like to start, talk with your doctor. They can discuss your individual benefits and risks and provide guidance on next steps.

There does seem to be a link between high-impact sports and the risk of arthritis, but injury contributes to that risk. For those that have already developed arthritis, consistent high-impact exercise can exacerbate symptoms.

That doesn’t mean that you have to give up high-impact workouts, though. The key is to practice thoughtfully and in moderation.

To minimize symptoms:

  • Don’t engage in high-impact sports or other activities that involve repetitive jumping every day. A general rule of thumb is to take a two- or three-day break in between high-impact sports. Your practice should only run for an hour tops.
  • Consider wearing a knee brace during practice. This can help keep your knee in proper position, particularly if the arthritis has compromised the alignment.
  • If you’re experiencing mild pain or swelling, take a nonsteroidal anti-inflammatory drug, such as naproxen (Aleve), after practice.

If you haven’t engaged in high-impact activities before, talk to your doctor before starting now. They can walk you through the potential impact these activities will have on your affected knee.

Bell is likely to advise her clients with arthritis to avoid high-impact activity altogether. She notes that jumping up and down creates an impact on your joints equal to about 20 times your body weight.

Learn more: An athlete’s guide to knee pain and osteoarthritis »

Although walking up and down stairs may hurt, it can be a good strengthening exercise for your leg and hip muscles.

The motion can also help increase joint fluid production, lubricating the joint and helping wash away toxins.

To safely climb steps:

  • Take your time. A “slow and steady” approach can help you maintain your stability.
  • Use the railing for support. If you currently use a cane, talk to your doctor about how to best use it while on stairs.
  • As with many other exercises, be careful not to overextend your knee.

For a low-impact alternative, try using a stair stepper machine. As with real steps, the repetitive motion will stimulate production of joint fluid.
When using a stair stepper, keep the following in mind:

  • Start with a shorter workout and increase the duration over time. Doing too much too quickly can be harmful.
  • Adjust the height of the rise to suit your needs. Bell advises that you start small and gradually work your way up to a higher step.
  • Use the railing for support, as needed. Be careful not to lean on the rails.

Learn more: Climbing stairs for knee pain relief »

Water aerobics are often suggested for recuperating from sore joints. Although the water can have a soothing, buoyant effect on your knees, Bell says it’s unlikely to produce enough resistance to strengthen the surrounding muscles.

“If you really want to create enough resistance to make a difference, land-based exercises ultimately are what you need,” she says.

Some of her favorites include cycling, at moderate or high intensity, and strengthening exercises like Pilates.

You may be able to get more out of a low-impact workout by incorporating weighted elastic bands or free weights into your routine.

You may also find it beneficial to wear a knee brace while exercising. If you haven’t already, talk with your doctor about whether this is a good option for you. They can make specific recommendations and advise you on best practices.

Check out: Best shoes for arthritis »

You’ll likely experience mild soreness when exercising, especially if you haven’t exercised for a while.

When planning your routine, be sure to keep the level of intensity reasonable. Your doctor or physical therapist can provide a personalized recommendation suited to your needs. The “dose” of exercise should be enough to produce a difference, but not so much that you become injured or discouraged.

Other tips

  • Invest in sneakers that are comfortable and provide proper support.
  • Always warm up before exercising. Stretching can help open up your joints and reduce the level of impact on your knees.
  • If your joints are already sore, apply heat before exercising to reduce potential stiffness.
  • Start with a 10-minute routine and increase the duration over time.
  • Break up high-impact exercise with low-impact modifications or alternatives.
  • Cool down after exercising. Take a few minutes to stretch out your joints. Applying a cold compress can also help reduce pain and swelling.

If you experience any of the following symptoms, stop exercising until you can see your doctor:

  • increased swelling
  • sharp, stabbing, or constant pain
  • pain that causes you to limp or change your gait
  • joints that feel warm to the touch or are red
  • pain that lasts more than two hours after exercise or worsens at night

If the pain persists, resist the temptation to mask it with painkillers, Bell says. You want to find out the underlying cause of the problem and fix it.

She also advises you to resist the urge to back off exercise altogether. After consulting your doctor, you should get moving again with an exercise regimen that’s tailored for you.

Keep reading: Natural home remedies for knee pain »

Not only is exercising with knee arthritis possible, it’s necessary to check or even reverse the pain associated with the condition. Bell notes that most states allow you to see a physical therapist without a referral, and that one or two sessions can result in an exercise prescription personalized for your goals and abilities.

“The worst thing you can do is nothing,” Bell says, adding that it’s best to optimize your workout before arthritis pain begins to slow you down. Using precautions while practicing can help you carry on with your preferred exercise routine for longer.