Abstract / Summary
Abstract Aims The effect of moderate-to-vigorous physical activity (MVPA) on knee/hip osteoarthritis (OA) remains inconclusive. We aimed to examine the association of accelerometer-measured MVPA and different MVPA patterns with OA. Methods We performed a prospective cohort study of 85,196 individuals from the UK Biobank. Participants were grouped according to BMI. MVPA were measured by wrist-worn accelerometers over a 7-day period. Restricted cubic spline (RCS) was used to evaluate dose-response associations between MVPA and OA. Based on RCS curves, intensity of MVPA were categorized as low, moderate, and high levels. Light physical activity (LPA) was also categorized into three levels for joint association analysis. Individuals achieving ≥ 50% of MVPA within 1–2 days were defined as weekend warriors (WW). Results During a median follow-up of 10.11 years, 5,017 knee/hip OA cases were identified. Among overweight and obese participants, MVPA showed a U-shaped association with knee/hip OA; among normal-weight and underweight participants, a J-shaped association was observed. In overweight and obese participants, moderate MVPA level was associated with the lowest OA risk compared with low and high levels. In underweight and normal-weight participants, low, moderate, and high MVPA levels showed comparable OA risk. The joint association analysis showed that the combination of moderate MVPA and moderate LPA conferred the lowest OA risk in overweight and obese participants, while in underweight and normal-weight participants, the combination of low MVPA and moderate LPA was associated with the lowest OA risk. At the same MVPA level, there was no significant difference in OA risk between the WW pattern and the regular pattern. Conclusions Among underweight and normal-weight individuals, OA risk gradually increased with higher MVPA levels. Moderate MVPA is recommended for overweight/obese individuals. Adding moderate LPA further reduces OA risk. Both WW and regular patterns are acceptable.