Staff Perspective: Examining the Relationship Between Exercise and Sleep

Staff Perspective: Examining the Relationship Between Exercise and Sleep

Tim Rogers, Ph.D.

Exercise is known to have several health-related benefits to include both physical and psychological. But what do we know about the relationship between exercise and sleep? Take a moment and think about what you have heard about sleep and exercise. Most people have probably heard that you should not exercise close to your bedtime as part of practicing good sleep hygiene. This is based on the rationale that you do not want the activation from a workout to potentially interfere with your ability to fall asleep. People also commonly believe that exercise would be helpful because it will make you feel tired, or burns off any excessive energy enabling you to fall asleep faster and more soundly (e.g., less nighttime awakenings). So it seems like exercise on a consistent basis may help people to fall asleep faster, decrease nighttime awakenings, and therefore possibly improve the quality of sleep. This blog will review key findings from literature on exercise and sleep functioning and summarize clinical recommendations.

Exercise, Bedtime and Falling Asleep:

In healthy populations, the National Sleep Foundation does not recommend any time restrictions for when a person should exercise. The only stipulation is that exercise should not occur at the expense of sleeping (e.g., sleep gets restricted to squeeze in a workout). For individuals with chronic insomnia, the National Sleep Foundation still recommends avoiding engaging in exercise during the late evening or night. Chennaoui et al. (2015) found in their review of sleep literature that the timing of exercise had a differential impact on its helpfulness with improving sleep onset latency (SOL), or ability to fall asleep. The authors found that exercise occurring between four and eight hours of an individual’s bedtime had the most positive impact. The same authors found that exercise that was more than eight hours or less than four hours prior to an individual’s bedtime had a negative impact (i.e., exercise did not demonstrate a decrease in the amount of time to fall asleep). Although positive effects have been found for both acute and regular exercise (i.e., decreased amount of time to fall asleep), regular and more vigorous exercise (e.g., aerobic exercise versus walking) are recommended. For individuals who are sedentary and not engaged in any exercise, even light exercise such as walking for 10 minutes a day can have a beneficial impact on reducing the amount of time to sleep asleep.

Exercise, Night Time Awakenings, and Total Sleep Time:

Similar to results of exercise on falling asleep, studies found that both acute and regular exercise demonstrated improvement in decreasing the amount of wake after sleep onset (WASO). The timing of the exercise appeared most beneficial between 4-8 hours of an individual’s bedtime (Chennaoui et al. 2015). Interestingly, multiple reviews found no significant difference between the total sleep time for those who engaged in exercise versus those who did not (Banno et al. 2018; Chennaoui et al., 2015). Some studies have found that sleep efficiency improved for individuals who engaged in regular exercise compared to those who did not in populations that do not have insomnia. For individuals with insomnia, Banno et al. (2018) found no significant differences in sleep efficiencies between those who engaged in an exercise program versus those who did not.

Exercise, Sleep Quality, and Daytime Functioning:

The National Sleep Foundation found that individuals who described themselves as exercisers were twice as likely report “I had a good night’s sleep” every night or almost every night on a workday compared to non-exercisers (2013). This finding was consistent regardless of how rigorous the exercise was (e.g., vigorous, moderate, or light exercise such as walking). Within the self-describe population of exercisers, 72% reported rarely or never had symptoms commonly associated with insomnia. Reviews of exercise and sleep functioning have also found significant differences in reported quality of sleep between those who exercise and those who do not. Individuals participating in regular exercise report higher subjective ratings of their quality of sleep, even if they have the same total sleep time as non-exercises (Banno et al. 2018; Chennaoui et al., 2015). It is also important to highlight that research has found that non-exercises report significantly higher symptoms of daytime sleepiness compared to those who exercise (National Sleep Foundation, 2013).

Clinical Recommendations:

The relationship between sleep and exercise is complex, bi-directional, and can have beneficial effects on sleep functioning, as well as an individuals physical and psychological well-being. Summarized below are some clinical recommendations based on a critical review of the literature.

1. Do not restrict sleep in order to exercise.

2. Do not exercise late in the evening or at night if you have chronic insomnia.

3. Regular exercise may improve an individual’s ability to fall asleep and decrease nighttime awakenings if the exercise occurs between four and eight hours of an individual’s bedtime

4. Although exercise may have beneficial effects on health and mood, it is not superior to other behavioral interventions such as stimulus control and or sleep restriction to improve insomnia symptoms.

The opinions in CDP Staff Perspective blogs are solely those of the author and do not necessarily reflect the opinion of the Uniformed Services University of the Health Science or the Department of Defense.

Timothy Rogers, Ph.D., is the Center for Deployment Psychology's Military Internship Behavioral Health Psychologist at Joint Base San Antonio, TX.

References:

Banno, M., Harada, Y., Taniguchi, M., Tobita, R., Tsujimoto, H., Tsujimoto, Y., … Noda, A. (2018). Exercise
can improve sleep quality: A systematic review and meta-analysis. PeerJ 6:e5172; doi: 10.7717/peerj.5172.

Chennaoui, M., Arnal, P.J., Sauvet, F., & Leger, D. (2015). Sleep and exercise: A reciprocal issue? Sleep
Medicine Reviews, 20, 59-72. doi: 10.1016/j.smrv.2014.06.008

National Sleep Foundation (2013). Poll on Exercise and Sleep. Retrieved from
https://www.sleepfoundation.org/media-center/national-sleep-foundation-poll-finds-exercise-key