Understanding Sleep Difficulties in the General Population
Prevalence of Sleep Issues
Over 25% of the general population experiences challenges with falling asleep, maintaining sleep, or achieving sufficient sleep duration. These sleep difficulties can elevate the risk of various medical conditions and may impact overall life expectancy.
Treatment Options for Sleep Disorders
In addition to medications and behavioral therapies, physical exercise has emerged as a potential treatment for sleep disorders. Research indicates that exercise can enhance various sleep parameters, including sleep onset latency, total sleep time, and overall sleep efficiency. However, current guidelines generally advise against nighttime exercise due to its possible negative effects on sleep.
Research Review on Nighttime Exercise and Sleep
Study Overview
To clarify the conflicting findings regarding nighttime exercise, researchers in Switzerland conducted a comprehensive review and analysis, published in the journal Sports Medicine. The researchers meticulously searched literature databases to identify studies assessing the impact of evening workouts on sleep in healthy adults.
Inclusion Criteria and Participants
The analysis focused on 23 studies, encompassing 275 participants who were classified as healthy and good sleepers. The predominant forms of exercise included cycling and running, with participants exhibiting varying levels of activity, from sedentary individuals to trained athletes. On average, participants exercised for approximately 87.4 minutes, concluding about 1.8 hours before bedtime, with workout intensities ranging from light to vigorous.
Findings on Sleep Variables
The review revealed no significant alterations in sleep variables typically associated with sleep quality, such as sleep onset latency, sleep efficiency, and wakefulness after sleep onset. This finding indicates that exercising close to bedtime does not adversely affect these sleep-related factors. However, a slight positive effect on sleep onset latency and efficiency was observed in those who exercised near bedtime, with no changes in total sleep time recorded.
Impact of Exercise on Sleep Stages
Data regarding time spent in various sleep stages suggested that nighttime exercise might contribute to a more restorative sleep experience. Notably, exercise intensity and duration did not correlate with significant changes in sleep variables.
Potential Negative Effects of Vigorous Exercise
Some studies within the review did report negative consequences on sleep quality following vigorous exercise that concluded less than one hour before bedtime. This could be attributed to insufficient recovery time for participants’ bodies and heart rates before sleep.
Conclusions and Future Research Directions
Overall Implications
The review concludes that exercising at night does not seem to lead to poor sleep outcomes. However, the authors acknowledge that several included studies were of low quality, which may limit the generalizability of the findings. Furthermore, the analysis was restricted to healthy adults without sleep disorders.
Recommendations for Future Research
Future studies should explore the effects of muscle inflammation or damage on sleep quality, particularly comparing vigorous exercise ending an hour or less before bedtime with moderate exercise at any time and vigorous exercise concluding at least two hours before sleep.
References
Stutz, J., Eiholzer, R., & Spengler, C. M. (2018). Effects of Evening Exercise on Sleep in Healthy Participants: A Systematic Review and Meta-Analysis. Sports Medicine. doi:10.1007/s40279-018-1015-0
Bergamin, F. (2018, December 13). Physical activity in the evening does not cause sleep problems. Retrieved December 17, 2018, from https://www.ethz.ch/en/news-and-events/eth-news/news/2018/12/physical-activity-in-the-evening-does-not-cause-sleep-problems.html