Recreational Running Causes Knee Osteoarthritis
It is a common misconception, held by both runners and healthcare professionals a that long-term habit of running increases the likelihood of developing knee OA
The facts of the matter are simple
If you do not already have knee OA then recreational running does not cause damage to the cartilage on the joint surfaces of the knee.
In fact running make actually help to protect both knees and hips from developing OA.
Knee OA is found at higher rates in non-runners but also in those who are training at an elite level.
A caveat to this is that it is unclear if the associations are causative or part of a picture relating to other risk factors like previous injury.
To put this in numbers: 3.5% of recreational runners have hip or knee OA. 10.2% of non-runners have the condition and 13.3% of ex-elite/professional international runners have hip or knee OA.
So what to do if a recreational runner already has OA?
Runners should feel that it is OK to run with knee OA. Ideally running less frequently will allow for sufficient cartilage recovery time.
Running does not appear to accelerate the progression of existing knee OA in runners over the age of 50.
It is currently not sold advice to tell a runner who has knee OA and is managing their symptoms, to stop running.
Unfortunately there is not clear optimal running dose for joint health in runners with or without knee OA.