Can Strength Training Help Osteoarthritis of the Knee?

December 5, 2021

by Cathe Friedrich

Has your doctor told you that you have knee arthritis? Osteoarthritis of the knee is the most common form of arthritis in people after the age of 50. Age is one risk factor for knee arthritis, but so is being overweight or obese.

Prior knee injuries also increase the likelihood of developing osteoarthritis of the knee. Research shows that people who sustain a knee injury, like a torn cartilage, have a six-fold higher risk of developing knee osteoarthritis by the age of 65.

Sitting Isn’t Beneficial for Your Joints

Osteoarthritis is a degenerative form of joint disease, although some studies suggest it may also have an inflammatory component. If you have it, you may experience varying degrees of pain, stiffness, reduced mobility, and swelling of the affected knee. These symptoms make it harder for some people to stay physically active but sitting on the couch is the worst thing you can do if you have osteoarthritis.

What happens if you become a couch potato? Without exercise, you will have diminished blood flow and nutrient delivery to your knee cartilage, as well as muscle atrophy. As the muscles that support your knees lose strength and size due to lack of movement, your knees have less support and stability. To maintain the muscles that support your knees, strength training is your best option. Muscles become thicker and stronger in response to strength training, and that’s what you need if you have arthritic knees.

Strength-Training and Knee Arthritis: Why You Need It

Many people with arthritis avoid strength training because they think it will worsen their arthritis, but the opposite may be true. Although over 100 types of arthritis exist, the most common is osteoarthritis, a degenerative form of arthritis that becomes more common with age. Achy knees and hips are often due to degeneration of the cartilage of the knee. In some cases, the cartilage thins down to the point where the bones almost rub against each other.

If your doctor diagnosed you with osteoarthritis, you might have concerns about exercising, believing it will worsen your joint pain. However, physical activity helps keep joints strong, flexible, and functional. There’s even evidence that exercise reduces the pain and stiffness that people with osteoarthritis struggle with. One reason arthritic knees are so uncomfortable is because of the stiffness that comes from lack of movement. Some doctors even refer to exercise as a “joint salve” for arthritis.

Build Quad Strength

Strength training also builds stronger quadriceps muscles, the main muscles that support your knees, and creates an added layer of protection against stress and impact on the joints. If you stick with it, you’ll thicken the muscles that shield and protect your knees. But be aware it takes time to build quadriceps strength, so you may not see the benefits for a few weeks to months.

Building strength takes time, but moving your body has immediate benefits for arthritic knees by increasing joint lubrication and nutrient delivery to the knee joint and by reducing joint stiffness. Stronger muscles around a joint also mean less stiffness when you move that joint. And if your muscle strength is low because of inactivity–as it is with most people with arthritis–strengthening exercises can even help prevent further damage to joints.

What Science Says about Strength Training and Osteoarthritis

Studies show strength training is beneficial for reducing pain and improving function in people with osteoarthritis. A study even found that people with severe osteoarthritis waiting on a joint replacement could benefit from strength training and do it safely. In fact, there’s evidence that strength training before surgery improves recovery after a knee replacement for arthritis. During recovery after knee replacement, lack of movement leads to muscle loss. Building muscle size and strength beforehand reduces muscle atrophy and makes it easier to regain the muscle you lost.

Strength training has the added benefit of helping with weight control. Knee osteoarthritis is more common in people who are overweight or obese because extra weight increases the force on the knees with each step, especially when climbing stairs. Moderate-intensity exercise also has an anti-inflammatory effect, which may make the pain and stiffness more manageable.

Guidelines for Strength Training with Osteoarthritis

Use lighter weights and higher repetitions, especially when you first start out. Choose a resistance that allow you to do 12 repetitions before the muscles are fatigued.
Do a 10-minute warm-up before picking up weights. The best warm-ups are dynamic, where your arms and legs are moving rather than static stretches. Save the stretches for the end of your workout.
Increase the resistance you use slowly, and don’t increase your training volume by more than 5% per week.
Use pain as your guide. If something is uncomfortable, modify it or don’t do it.
Don’t work the same muscle groups again for 48 hours. Rest and recovery are even more important if you have arthritis.
Avoid high-impact exercise where both legs leave the ground simultaneously.
If you have moderate to severe arthritis, consider seeing a physical therapist so they can design a workout plan that is safe and effective for you.
More isn’t necessarily better. You can get significant benefits from 2 or 3 strength-training sessions per week and spacing them out will give your muscles and joints more time to recover.

The Bottom Line

Science shows that strength training has multiple benefits for arthritic knees. If you have severe knee arthritis, sessions with a physical therapist are the best way to start. If you have mild to moderate knee arthritis, take it slow, focus on form, and listen to your body. But keep moving!

References:

“Weightlifting with Arthritis: Is It Good or Bad for You?.” news.hss.edu/dr-sutton-weight-lifting-with-arthritis-is-it-good-or-bad-for-you/.
“Strength Training for People with Arthritis – Living With ….” 05 Jan. 2018, blog.arthritis.org/living-with-arthritis/strength-training-types/.
“Strength Training for Arthritis: I’ve Never Loved My Body More.” 26 Apr. 2018, healthline.com/health/i-did-weight-training-for-joint-pain-but-ive-never-felt-more-beautiful.
“Strength training: Get stronger, leaner, healthier – Mayo ….” 15 May. 2021, mayoclinic.org/healthy-lifestyle/fitness/in-depth/strength-training/art-20046670.
“Physical Activity for Arthritis | CDC.” cdc.gov/arthritis/basics/physical-activity-overview.html.
“Exercise: Rx for overcoming osteoarthritis – Harvard Health.” 24 Jun. 2019, health.harvard.edu/staying-healthy/exercise-rx-for-overcoming-osteoarthritis.
Vincent, K. R., & Vincent, H. K. (2012). Resistance exercise for knee osteoarthritis. PM & R : the journal of injury, function, and rehabilitation, 4(5 Suppl), S45-S52. doi.org/10.1016/j.pmrj.2012.01.019.
“5 Surprising Facts About Osteoarthritis Of The Knee Pain ….” 24 Sept. 2016, https://arrowheadhealth.com/osteoarthritis-knee-pain/.
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“Exercise for osteoarthritis of the knee: a Cochrane ….” 01 Dec. 2015, https://bjsm.bmj.com/content/49/24/1554.