Very high and very low levels of activity may harm knees: study

Chicago – Engaging in too much or too little physical activity can hasten the degeneration of knee cartilage, concludes a study from the University of California in San Francisco.

Researchers used MRI technology to analyze knee cartilage changes over a four-year period among 205 patients 45-60 years old from the UCSF-based Osteoarthritis Initiative. Results indicated that participating in high-impact sports such as running was associated with more cartilage degeneration and a higher risk for developing osteoarthritis. The same was true for people with very low levels of physical activity, according to the study abstract.

The findings suggest the possibility of an “optimal level of physical activity to preserve the cartilage,” researchers said in a press release.

The Centers for Disease Control and Prevention estimates that 1 out of 2 people may develop osteoarthritis by age 85. For people at higher risk of osteoarthritis due to obesity, knee surgery or a family history of joint replacement, researchers suggested maintaining a healthy weight and participating in lower-impact sports, such as swimming or walking, rather than high-impact ones, such as running.

The study was presented Nov. 26 at the annual meeting of the Radiological Society of North America.