Ask three people whether walking is good for arthritic knees and you'll get "yes," "no, it wears them out," and "depends on the day." The research is more consistent than that, though narrower than most headlines make it sound. Most of what follows rests on one study, so we'll start there.
The study
Grace Lo and colleagues at Baylor College of Medicine published it in Arthritis & Rheumatology in 2022. They used the Osteoarthritis Initiative, a long-running observational study sponsored by the US National Institutes of Health, and picked out 1,212 participants aged 50 or older whose X-rays showed knee osteoarthritis. Of those, 73% had reported walking for exercise (the cutoff was 10 or more occasions of walking for exercise at age 50 or later) and 27% hadn't. Four years on, the researchers checked who had developed frequent knee pain, meaning pain, aching or stiffness on most days, and whether the X-rays had worsened.
Among people who didn't have frequent knee pain at the start, walkers had about 40% lower odds of developing it. The X-ray findings were weaker: narrowing of the inner joint space was less common in walkers, and the authors described the structural results as preliminary.
"Walking wears out arthritic knees"
Not supported. This is the claim the study speaks to most directly, and it didn't hold up. Among people who already had arthritis on X-ray, the ones who walked for exercise were less likely, not more, to end up with daily knee pain four years later. That doesn't prove walking protected them, which we'll come back to, but it's hard to square with the idea that walking itself was doing the damage.
"Walking is a treatment"
Be careful. The benefit was for new pain. One of the study's four outcomes was whether existing frequent pain improved, and according to press coverage of an interview with Lo, walkers weren't more likely than non-walkers to see their pain resolve once it was established. Her advice, as reported, was that people with knee arthritis should walk, especially if they don't have daily knee pain. If you do have daily pain, she said, there still might be a benefit, particularly with bow-legged knees. "Might" is the operative word.
"It will flare it up"
Real, but the data lean the other way. Pain flares after activity are common in knee arthritis, so the worry isn't imaginary. A separate Osteoarthritis Initiative analysis in Osteoarthritis and Cartilage looked at flares during a 20-metre walk at a usual pace, defined as a rise of at least 2 points on a 10-point pain scale. Knees belonging to habitually more active people had lower odds of a flare, an odds ratio of about 0.7. "Active" there meant a general activity score, not walking specifically, so it's a loose fit. Still, it points opposite to the instinct that rest keeps the knee calm.
"How much should I walk?"
The study can't say. Counting 10 or more occasions of walking for exercise after turning 50 is a low and loose bar. It doesn't separate a few strolls a month from an hour every morning, so there is no dose-response here to build a plan on. Anyone quoting an exact number of minutes that protects the knee is extrapolating.
Why to hold it loosely
It's observational, and the exposure was self-reported. People with healthier knees probably walk more, which could produce the same pattern without walking doing anything. The authors called their results a glimmer of hope for an inexpensive intervention, and that is about the right register. A randomised trial of walking in knee arthritis with long enough follow-up would settle more than this can.
What we'd do with it
If you have knee arthritis and your knees tolerate it, walking is worth keeping or starting. Begin with a length that leaves you only mildly sore the next day, add a few minutes a week, and judge by how the knees feel the following morning rather than during the walk. Ordinary aching is one thing. Sharp pain, new swelling, locking or giving way is another, and that's a question for a clinician or physiotherapist, who can also tailor the plan to the kind of arthritis you have.
Some people find that surface and footwear make a difference; we cover both in walking and joint health and best walking shoes. If you're over 60 and building up from very little, walking for seniors has a gentle progression, and walking for back pain covers the overlapping question for the spine.
Sources
- Lo GH, Vinod S, Richard MJ, et al. Association between walking for exercise and symptomatic and structural progression in individuals with knee osteoarthritis: data from the Osteoarthritis Initiative cohort. Arthritis & Rheumatology. 2022. doi:10.1002/art.42241
- Baylor College of Medicine. Walking towards healthier knees. News release. bcm.edu
- Urban P. Arthritic knee? Take a walk. AARP, June 21, 2022 (summary of the study design, with quotes from the authors). aarp.org
- Physical activity and risk of pain flare induced by walking: the Osteoarthritis Initiative. Osteoarthritis and Cartilage. oarsijournal.com
- Knee pain from arthritis may be prevented by walking, study says. Fox News (report including comments from Lo on people who already have frequent pain). foxnews.com
We checked the details above against the journal abstract, Baylor's news release and AARP's write-up on October 2, 2026. We could not open the full text of the 2022 paper, so figures beyond those sources, such as exact confidence intervals, are left out. This is general information, not medical advice. If you have persistent knee pain, see a clinician.