Is running bad for your knees? Debunking the biggest running myths

While high-impact movement might sound damaging, running actually helps strengthen the muscles, ligaments, and cartilage that support the knee joint.

Professor Stuart Gray works at the University of Glasgow and is an expert in muscle and metabolic health.

He told BBC Bitesize that the risk of conditions which can impact our knee health is slightly lower in people who run in their spare time than in people who don’t get a lot of exercise. Prof Gray explained that “Running strengthens cartilage and muscle providing greater strength and stability around the knee joint.”

He added there are some situations where it can be bad, especially when people start running further distances than they’re used to. If, for example, someone started running far more than they were used to while preparing for a marathon, there is a possibility it could lead to a knee injury.

The North Run (the UK’s most famous half marathon), further debunks this myth and emphasises Prof Gray’s words by claiming knee problems are more likely to come from training errors rather than running itself. Increasing mileage too quickly, poor running form, inadequate footwear, or pushing through pain are the real culprits. With a gradual training plan, good technique, and proper recovery, running can actually support joint health rather than harm it.