Regular but light exercise may be able to delay the onset of osteoarthritis in people who are most at risk from the disease.

A team from the University of California, San Francisco, US lead by professor Thomas Link, found that while strenuous physical activity can increase the damage to joints, lighter forms of exercise is beneficial to patients.

"Participating in a high-impact activity, such as running, more than one hour per day at least three times a week appears associated with more degenerated cartilage and potentially a higher risk for development of osteoarthritis", Link said.

"Engaging in light exercise, however, and refraining from frequent knee-bending activities may protect against the onset of the disease."

Osteoarthritis, also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone.

The findings also showed that frequent knee-bending activities, such as climbing up stairs, lifting objects weighing more than 25 pounds and deep knee bending for at least 30 minutes per day, were associated with cartilage abnormalities.

Link added: "People can reduce the risk of osteoarthritis by maintaining a healthy weight and avoiding risky activities and strenuous exercise.

"Lower-impact sports, such as walking, swimming or using an elliptical trainer are likely more beneficial than high-impact sports, such as running or tennis."