SummarySleep disturbances are common in individuals with posttraumatic stress disorder. Exercise interventions are a promising approach in the treatment of sleep disorders, but little is known about the efficacy of exercise interventions for sleep disturbances associated with posttraumatic stress disorder. A total of 40 individuals with posttraumatic stress disorder were randomized to six sessions of either high‐intensity interval training or low‐to‐moderate‐intensity training, administered within 12 days. Sleep quality was assessed over 24 days from baseline to post with the Pittsburgh Sleep Quality Index, a sleep log, and a waist‐worn actigraphy. Analyses revealed that, regardless of group allocation, Pittsburgh Sleep Quality Index score improved significantly by 2.28 points for high‐intensity interval training and 1.70 points for low‐to‐moderate‐intensity training (d = 0.56 for high‐intensity interval training; 0.49 for low‐to‐moderate‐intensity training) over time, while there were no significant changes in any sleep log or actigraphy measure. Analysis of a subsample of those affected by clinically significant sleep disturbances (n = 24) revealed a significant time effect with no difference between exercise interventions: Pittsburgh Sleep Quality Index improved significantly by 2.65 points for high‐intensity interval training and 2.89 points for low‐to‐moderate‐intensity training (d = 0.53 for high‐intensity interval training; 0.88 for low‐to‐moderate‐intensity training), and actigraphy measure of wake after sleep onset was reduced significantly by 14.39 minutes for high‐intensity interval training and 6.96 minutes for low‐to‐moderate‐intensity training (d = 0.47 for high‐intensity interval training; 0.11 for low‐to‐moderate‐intensity training) from baseline to post. In our pilot study, we found an improvement in sleep quality from pre‐ to post‐assessment. There were no significant differences between exercise groups. Further studies are needed to investigate whether the found time effects reflect the exercise intervention or unrelated factors.
