The evidence-led answer
NST verdict
For most people, no. Recreational running is linked to less knee and hip arthritis than being sedentary, not more. In a pooled analysis of over 125,000 people, arthritis was about three times less common in recreational runners than in inactive people, and runners were also less likely to end up needing a knee replacement. Cartilage is living tissue that adapts to load; it is not a fixed amount that running spends. Risk does go up at the extreme end, since decades of high volume competitive running show higher arthritis rates, so it looks like a U shape: too little movement and a lot of very hard running both associate with more wear, with moderate recreational running in the low risk middle. The big drivers of knee arthritis are a prior joint injury, excess body weight and genetics. If you already have knee arthritis, a past serious knee injury, or ongoing knee pain, get individual advice before ramping up, but "running will ruin your knees" is not what the evidence says.
Does running "wear out" your knees?
The "wear and tear" picture, cartilage as a fixed pad that every run grinds down a bit more, is not how joints work. Cartilage is living tissue that responds to load: regular, moderate loading is part of what keeps it healthy, and long periods of unloading are bad for it. Randomised trials that tracked knee cartilage on MRI found that knee loading exercise did not appear to harm cartilage, even in people already at risk of or living with knee osteoarthritis, though the researchers rated the overall quality of that evidence as low.
What does the evidence actually show?
That recreational runners have less hip and knee arthritis than people who do not run. A pooled analysis of 25 studies and about 125,800 people found the prevalence of hip and knee osteoarthritis was 3.5% in recreational runners versus 10.2% in sedentary controls. A second pooled analysis found running was associated with lower odds of having knee replacement surgery for arthritis, a pooled odds ratio of 0.46, meaning roughly half the odds. Its findings on an arthritis diagnosis were more mixed, and it concluded the evidence could not settle the question either way.
So when is running a problem for knees?
At the extremes, and with a damaged joint. In the same large pooled analysis, competitive runners, professionals, international level athletes, often with decades of very high mileage, had a higher arthritis prevalence, 13.3%, than both recreational runners and sedentary people. So the relationship looks like a U shape: a sedentary lifestyle and many years of very high volume hard running are both linked to more hip and knee arthritis, with ordinary recreational running in the low risk dip between them.
Two caveats keep this honest. First, these studies are observational; they compare people who chose to run with people who did not, so healthier people self selecting into running, and previous injuries, could explain part of the difference, and the researchers say causation cannot be proven. Second, the biggest known risk factors for knee arthritis are a previous significant joint injury, carrying excess weight, and genetics, not recreational running itself. What the data rules out is the idea that normal recreational running ruins healthy knees.
What this means in practice
If your knees are healthy, recreational running is fine and probably good for them. Build your volume up gradually rather than in big jumps, keep most of your running easy, and add some leg strength work, since strong muscles around a joint help it handle load. Do not run through sharp or worsening joint pain; mild aches after a new training load that settle down are normal, but a knee that hurts more each run is a signal to back off and get it looked at. If you already have knee osteoarthritis, a past serious knee injury, or persistent knee pain, get individual guidance from a physiotherapist or doctor before increasing your running. It may well still be fine for you, but it should be managed rather than guessed at. For long term knee health, keeping your body weight in a healthy range and building leg strength matter more than whether or not you run.
Practical meaning
If your knees are healthy, recreational running is fine and probably good for them: build volume gradually, keep most runs easy, add leg strength work, and do not run through sharp or worsening joint pain. If you have knee osteoarthritis, a past serious knee injury or persistent pain, get individual guidance from a physiotherapist or doctor before ramping up. Managing body weight and building leg strength do more for knee health than avoiding running. General information, not medical advice.
Limitations and uncertainty
The running and arthritis studies are observational: they show recreational running is associated with lower arthritis rates, not that it causes them, because runners may differ from non runners in other ways. The cartilage MRI evidence is low quality and mostly studied strengthening exercise, not running. The 'competitive' category mixes elite athletes with very long exposure runners, and no mileage threshold for higher risk is defined. Acute running injuries are a separate topic.
No product needed
This page is here to answer the question, not force a product.
Some research pages are deliberately product-free because adding a retailer link would not help the reader make a better decision. When a product is genuinely relevant, it appears after the evidence and is clearly labelled.