High impact exercises such as running were found to damage ligaments further

A US study of more than 200 people aged 45 to 55 and of ‘normal’ weight, found those doing the most exercise were the most susceptible to knee damage.

The damage seen was associated solely with activity levels, and was not gender or age specific, researchers said.

Researchers also said that high impact exercise such as running and jumping do more damage to cartilage and ligaments than gentler exercises such as swimming and cycling.

Osteoarthritis, the most common form of arthritis, is a degenerative joint disease that causes pain, swelling and stiffness and affects 8 million people in the UK. It is more common in women and the risk increases with age and weight.

Study leader Dr Christoph Stehling, a researcher at the University of California said, ‘Our data suggests that people with higher physical activity levels may be at greater risk for developing knee abnormalities, and thus, at higher risk for developing osteoarthritis’.

However, a spokeswoman for the Arthritis Research Campaign said that the gains of exercise far outweighs any potential risks, ‘We have known for years that certain high impact sports ad jobs are associated with an increased risk of osteoarthritis, particularly of the knee, but for the vast majority of people exercise is good, not only for cartilage but for total body health’.