Objectives: To examine 1) the chronic effects of a 20-week physical exercise program on device-assessed sleep and on sleep-disordered breathing (SDB); and 2) whether attending to a session of the exercise program had effects on device-assessed sleep the subsequent night in children with overweight/obesity.
Methods: A total of 99 children with overweight/obesity (n=47 in the exercise group) participated in this secondary analysis of the ActiveBrains randomized clinical trial. The exercise program included a combination of aerobic and resistance exercise training, 3-5 days/week (90 min/session). The control group was asked to maintain usual lifestyle. Sleep outcomes were measured using wrist actigraphy and included: total sleep time, total time in bed, sleep efficiency, and wake after sleep onset (WASO) time. SDB was assessed via the Paediatric Sleep Questionnaire.
Results: The ActiveBrains exercise program had a statistically significant effect on WASO time (-10.8 min/day, -0.5 standard deviations (SD), P=0.040). Furthermore, we observed a small non-statistically significant effect on sleep efficiency (+2%, 0.4 SD, P=0.1). No other chronic effects were observed on the other sleep outcomes. The nights (at maximum of 4) after attending the ActiveBrains exercise sessions, children showed higher total sleep time (+8 min, P=0.17), sleep efficiency (+1%, P=0.15), and lower WASO time (-6 min, P=0.18) although did not reach statistical significance.
Conclusion: A 20-week physical exercise program reduced WASO time in children with overweight/obesity in comparison with control group peers, yet we did not observe effects on SDB. Future randomized trials that include a clinical sample of children with poor sleep health at baseline are needed to better appreciate the role of exercise in sleep health.