Trial results for an intervention using wearable activity trackers and a new application to improve physical activity in knee osteoarthritis were posted on ClinicalTrials.gov on 2025-10-06. The study found an adjusted mean increase of 13.1 minutes in daily moderate/vigorous physical activity.
Background
Physical activity is an essential first-line treatment for patients with knee osteoarthritis (OA). However, only 13% of patients currently meet the recommended activity level of 150 minutes or more per week. This trial aimed to assess the efficacy of a digital health intervention to improve physical activity and reduce sedentary time in this patient population.
Trial design
This completed randomized controlled trial, designated as Phase NA, enrolled 51 participants with conditions including Joint Diseases and Knee Osteoarthritis. The intervention involved a Fitbit Flex wearable activity tracking device paired with a new application, supplemented by a brief education session and telephone counseling provided by a physiotherapist. The primary goal was to assess the efficacy of this combined approach.
Key results
Key analyses revealed the following:
- For the main comparison of daily moderate/vigorous physical activity at 13 weeks, an ANCOVA analysis showed an adjusted difference in mean change of 13.1 minutes (95.0% Confidence Interval: 1.6 to 24.5) between groups, with a p-value of 0.05.
- For daily sedentary minutes, an ANCOVA analysis showed an adjusted difference in mean change of -29.5 minutes (95.0% Confidence Interval: -75.8 to 16.7) between groups, with a p-value of 0.05.
Selected key measurements for daily moderate/vigorous physical activity included:
- Immediate Group: Mean of 31.0 minutes per day (Standard Deviation 37.3)
- Delayed Group: Mean of 71.3 minutes per day (Standard Deviation 99.8)
- Immediate Group: Mean of 37.0 minutes per day (Standard Deviation 32.3)
- Delayed Group: Mean of 74.6 minutes per day (Standard Deviation 102.1)
Selected key measurements for daily sedentary minutes included:
- Immediate Group: Mean of 567.5 minutes per day (Standard Deviation 183.1)
- Delay Group: Mean of 551.1 minutes per day (Standard Deviation 234.9)
What this means
The results suggest that an intervention combining wearable activity trackers, a dedicated application, education, and physiotherapy counseling can significantly increase daily moderate/vigorous physical activity in patients with knee osteoarthritis. The adjusted mean increase of 13.1 minutes in daily activity could contribute to better management of the condition, given that physical activity is a cornerstone of treatment. While a reduction in sedentary time was also observed, the confidence interval for this outcome was wider, indicating less certainty in the magnitude of this effect.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT02585323, titled "SuPRA: Using Wearable Activity Trackers With a New Application to Improve Physical Activity in Knee Osteoarthritis", were posted on 2025-10-06 on clinicaltrials.gov.