Exercise and Knee Arthritis: What the Latest Research Really Says

Motion Is Medicine: What the Latest Research Really Says About Exercise and Knee Arthritis

A plain-language guide for nurses, caregivers, and anyone living with knee osteoarthritis

If you or someone you care for has knee osteoarthritis (OA), you've probably heard "exercise is good for it" a hundred times. But which exercise? And is it really safe when the joint already hurts?

A large 2025 study by Yan and colleagues set out to answer exactly that. Researchers pulled together results from more than 200 clinical trials involving thousands of adults with knee OA, comparing nine different types of exercise side by side. Here's what they found, broken down simply.

The Short Version

Almost every type of exercise helped — with aerobic exercise and strength training coming out on top for reducing pain and improving how well people could move.

What Counts as "Exercise" Here?

The study looked at a wide range of options, so there's likely something for everyone:

  • Aerobic exercise — walking briskly, cycling, swimming, low-impact classes

  • Resistance (strength) training — building muscle around the knee

  • Aquatic exercise — water-based movement, easier on painful joints

  • Yoga and tai chi — gentle, mind-body movement

  • Neuromuscular and balance training — improving coordination and stability

  • Flexibility/stretching

  • Combined programs — mixing several of the above

The Big Takeaways

1. Moving beats not moving

Compared to usual care or no exercise, most programs led to real improvements in pain, function, mobility, and quality of life. Exercise isn't just "worth a try" — it's genuinely effective.

2. Aerobic exercise led the pack

Things like brisk walking, cycling, and swimming consistently ranked as the most effective option overall for cutting pain and boosting function.

3. Strength training was a close second

Building the muscles around the knee seems to take pressure off the joint itself. Participants who did resistance training saw less pain, better joint stability, and easier walking.

4. Combining exercise types worked especially well

Programs mixing aerobic work, strengthening, flexibility, and balance training often outperformed single-type programs — likely because they tackle the problem from multiple angles at once.

5. Yoga and tai chi have real value too

These lower-impact, mind-body approaches improved pain, balance, and mobility — a great option for older adults or anyone who prefers gentler movement.

6. Water-based exercise is a smart alternative

For people who struggle with weight-bearing exercise (due to pain, weight, or balance concerns), aquatic exercise offered similar pain and function benefits without the joint strain.

7. It's safe

This is the part patients worry about most. The good news: side effects were uncommon and usually mild — mostly just temporary muscle soreness. Supervised, well-designed exercise programs were not linked to serious harm.

For Nurses: How to Use This in Practice

  • Lead with reassurance. Many patients avoid exercise out of fear of "making it worse." This evidence supports telling them that some initial discomfort is normal and exercise is safe.

  • Personalize the plan. Not everyone can or wants to walk or jog. Offer alternatives — water aerobics for those with weight-bearing pain, tai chi or yoga for those wanting gentler options.

  • Push for combination programs when possible. Aerobic + strength + flexibility + balance appears to deliver the broadest benefit.

  • Set expectations, not promises. Long-term adherence and lasting benefit weren't as strongly established in the research, so encourage exercise as an ongoing habit, not a short course of treatment.

  • Refer appropriately. Physical therapy or supervised exercise programs may improve both safety and results, especially for patients new to exercise.

For Patients and the Public: What to Actually Do

  1. Start moving, even a little. Walking, swimming, or a stationary bike are excellent starting points.

  2. Add strength work if you can. Simple resistance exercises (bands, bodyweight, light weights) targeting the leg muscles can meaningfully reduce pain over time.

  3. Try water exercise if land-based movement hurts. It's gentler on the joints while still effective.

  4. Consider yoga or tai chi, especially if you want something low-impact that also helps with balance.

  5. Expect some soreness at first — this is normal and not a sign of damage. Serious problems were rare in the research.

  6. Mix it up. A varied routine (some aerobic, some strength, some stretching) tends to work better than sticking to just one type.

A Few Honest Caveats

  • Exercise "dose" varied a lot between studies — some were supervised by professionals, others weren't, and intensity differed.

  • The research is strongest for short-to-medium term benefits; less is known about very long-term outcomes.

  • Some exercise types had fewer studies behind them, so those comparisons are less certain.

Bottom Line

Exercise isn't just a "nice to have" for knee osteoarthritis — it's one of the most effective, evidence-backed tools available, and it's safe for most people. Aerobic exercise and strength training stand out as the strongest options, but the best exercise is ultimately the one a person will actually stick with.

Based on: Yan et al. (2025), systematic review and network meta-analysis of exercise interventions for knee osteoarthritis.