Increased Physical Activity Improves Sleep and Mood Outcomes in Sedentary People with Insomnia: A Randomized Controlled Trial

Introduction: Lower levels of regular physical activity are an independent risk factor for insomnia incidence and prevalence. The impact of public health initiatives to increase physical activity on sleep outcomes of people with chronic sleep disorders remains mainly unexplored. The present trial was designed to investigate the effects on sleep quality of increasing physical activity to currently recommended levels among sedentary people with insomnia.

Methods: 41 sedentary adults with DSM-IV insomnia symptoms (30 female; mean age 59.8 +/-9.5) were randomized to a physical activity group (> or =150 minutes moderate intensity activity/week) or a waiting list control group. The principal end-point was Insomnia Severity Index (ISI) change 6 months post baseline; secondary outcomes were anxiety (STAI/Trait) and depression (Beck Depression Inventory). Physical activity was assessed using ActiGraph GT3X+ accelerometers. Outcomes were assessed in univariate general linear models, adjusted for baseline confounders.

Results: Activity and sleep assessments did not differ at baseline. At 6 months post baseline the intervention group engaged in 213 min/week of moderate intensity PA, compared to the control group (82 min/week). Compared to the control group, the intervention group showed significant improvement in the ISI score at 6 months F (1,28)=5.16, p<0.05), adjusted means difference=3.37, with an adjusted Cohen’s d=.78 [95% CI .10-1.45]. There was a significant effects improvement in trait anxiety, and depression outcomes post-intervention, F(6,28)=4.41, p=0.05, and F(6,28)=5.61, p=0.02, respectively.

Conclusion: Increasing activity in line with current recommended World Health Organization guidelines can deliver clinically significant improvements in sleep quality and mood outcomes among sedentary people with insomnia.