Association Between #Weight Loss and Spontaneous Changes in #Physical Inactivity in Overweight/Obese Individuals With Knee Osteoarthritis: An Eight‐Week Prospective Cohort Study

To describe spontaneous changes in time spent being physically inactive that is measured continuously by accelerometry during an 8‐week weight‐loss intervention in overweight/obese individuals with knee osteoarthritis (OA)..

A total of 124 participants completed the dietary intervention and had valid accelerometer recordings. The mean weight loss was 12.7 kg (95% confidence interval [95% CI] –13.2, –12.1; P < 0.0001) after 8 weeks, which corresponded to a decrease in body mass index of 4.3 kg/m2 (95% CI –4.5, –4.2; P < 0.0001). Significant improvements in OA symptoms (assessed by the Knee Injury and Osteoarthritis Outcome Score [KOOS]) was found across all subscales; an improvement of 12.8 points (95% CI 10.6, 15.0; P < 0.0001) was observed for pain using the KOOS. No statistically significant change occurred in the average daily time spent inactive from baseline to follow‐up (mean change 8.8 minutes/day [95% CI –12.1, 29.7]; P = 0.41).

Physical inactivity remains stable despite a clinically significant weight loss and improvements in knee OA symptoms. Change in inactivity does not seem to occur spontaneously, suggesting that focused efforts to reduce inactive behaviors are needed.