Effects of an acute bout of light-intensity walking on sleep in older women with sleep impairment: A randomized controlled trial

Study objective: This study aimed to explore the effects of a single bout of light-intensity walking on sleep in older women with mild sleep impairment. Methods: A total of 40 women aged 55 years or above with mild sleep impairment were randomized to either a treadmill-walking session for 50 mins or a quiet-rest control. All participants completed the study (mean age: 60.4±4.7). Sleep quality was assessed by ActiGraph for 2 nights before (pre-test) and 2 nights after exercise (post-test). A mixed-design analysis of variance was used with group as the between-subjects factor and time point as the within-subjects factor. Results: No significant group difference on demographic variables, body mass index, physical and mental status, and eight sleep parameters were observed at baseline. Significant group-time interactions existed for sleep latency (p<0.001) and sleep efficiency (p=0.025). After the intervention, the walking group reduced sleep latency by 3.3 minutes (p=0.001) and also had greater sleep efficiency (increase 3.8%, p=0.008), but no significant change was found in the control group. No significant group-time interactions were present for the other six sleep parameters (activity counts, total sleep time, wake after sleep onset, number and length of awakenings, or time in bed). Conclusion: A single session of light-intensity walking led to a modest reduction in sleep latency and improvement of sleep efficiency in older women with mild sleep impairment.