Gilbert AL, Lee J, Song J, et al. - In this study, the cross-sectional association between restless sleep and physical activity in participants with or at risk for knee osteoarthritis (OA) was explored. Researchers examined accelerometer-measured physical activity and clinical data of participants included in the Osteoarthritis Initiative (OAI). Multiple regression analysis was used to assess physical activity for participants, who were grouped by the reported frequency of restless sleep, and adjusted for demographic and medical confounders. They enrolled 1,892 OAI participants, 300 participants (16%) reported restless sleep ≥ 3 days in the past week. An association was found between poor sleep quality and less physical activity in persons with or at risk for knee OA. There is a need for further trials to ascertain the mechanisms of how poor sleep and physical activity are related, how energy and depression mediate these associations, and if interventions that improve sleep quality might result in increased physical activity.