Fluctuations in Self-Reported Symptoms Predict Objective Physical Activity in Adults With Type 2 Diabetes

Purpose: The purpose of this study was to examine the association between self-reported symptoms including fatigue and sleep disturbance with moderate-intensity physical activity among adults with type 2 diabetes. Methods: This report was a secondary analysis of a cross-sectional study. Data from 53 participants with at least 6 days of repeated measures were used. Daytime physical activity and energy expenditure were assessed using a wrist-worn accelerometer at the free-living setting. Fatigue upon awakening was measured using a 0 to 10 scale. Sleep (eg, restorative sleep, sleep duration, and sleep efficiency) was measured using the Consensus Sleep Diary for Morning. Data were analyzed using linear mixed models by including within- and between-person effects. Results: Participants were predominantly females (54.7%) with a mean age of 60.3 years. Controlling for the covariates, at the individual level (within-person), fluctuations in restorative sleep and fatigue upon awakening predicted moderate-intensity PA. Similarly, at the individual level, fluctuations in restorative sleep and fatigue upon awakening predicted average hourly energy expenditure. However, at the group level (between-person), no significant associations were found between fatigue and restorative sleep with moderate-intensity physical activity. Conclusions: The study findings suggest that within-person fluctuations in fatigue and restorative sleep upon awakening predict daytime moderate-intensity physical activity. At the individual level, reducing fluctuations in fatigue and restorative sleep might encourage participation in physical activity. More research is warranted to uncover the underlying causes of fluctuations in fatigue and restorative sleep. Meanwhile, diabetes care and education specialists should pay attention to the within-person fluctuations of fatigue and sleep.