Neither Vigorous Activity nor Sedentary Behavior Is Associated with Risk for Knee Osteoarthritis

Patients and some clinicians still are concerned that physical activity, particularly vigorous physical activity, might be associated with excess risk for knee osteoarthritis (OA), despite considerable evidence to the contrary. Researchers revisited the issue in a prospective cohort of 1194 adults (mean age, 58; mean body-mass index [BMI], 27 kg/m²) who were at high risk for developing knee OA based on weight, history of knee injury or knee surgery, lack of confidence in knee stability, and modified lifestyle due to concerns about knee damage.

Patients were classified by physical activity trajectory and sitting behavior, which were measured at baseline and at least twice during the subsequent 8 years. Physical activity trajectories were: per…