Issue #61 – September/October 2019
Welcome to Focus on Fatigue!
These days, we’re all familiar with the three pillars of health: nutrition, exercise and sleep. Each one comes with its own set of rules that seem to get more complex with every internet article we read. That’s before we even start to look at all the ways our three pillars interact! It’s not a wonder we sometimes feel overwhelmed by all the available, and sometimes contradictory, information.
In this month’s Focus on Fatigue, we’ll attempt to untangle one aspect of the interaction between exercise and sleep. Can you exercise at night and still get a good night’s sleep? The findings may just help you rest easy.
The FRMS Team
InterDynamics Pty Ltd
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Tel +61 7 3229 8300
Views expressed in articles and links provided are those of the individual authors, and do not necessarily represent the views of InterDynamics (except where directly attributed).
Exercise and Sleep: Can One Follow the Other?
Exercise. It’s like a little shot of goodness for your mind and body. Studies have found that regular doses of exercise will help you feel better on the inside and look better on the outside. You’ll be happier, more relaxed, less likely to get sick, have more energy during the day, and even have a better memory. Exercise will also help you sleep better. In fact, exercise can help you go to sleep faster, stay asleep longer, and wake up less often during the night.
So, what the problem?
At some point in the past, people began to wonder if exercising at night was such a good idea. Would evening exercise interfere with getting a good night’s sleep? There seemed to be three main hypotheses around this idea:
- Exercise increases core body temperature and stimulates the nervous system, which could make it more difficult to fall asleep;
- Exercise could lead to a stress response in people with low fitness levels, which could interfere with sleep; and/or
- Muscle soreness resulting from exercise could make it hard to sleep.
Are any of these hypotheses true?
All of these hypotheses have been tested over time. At first, researchers looked mainly at how much time elapsed between when participants worked out and when they went to bed. However, more recent studies have included variables such as exercise intensity and duration. While the findings have sometimes been contradictory, a recent meta-analysis of the research found that exercise in the evening does not seem to negatively affect sleep. In fact, there is the potential that evening exercise improves sleep, however the effects were small and possibly due to normal variations in sleep patterns.
One possible exception
There could possibly be some interaction effects between variables such as exercise intensity and duration that do have some impact on sleep. For example, some studies have found that sleep may be slightly impaired if the exercise is vigorous, and performed within an hour of bedtime. This may be due to an increase in heart rate, which takes time to calm down. The data here is far from conclusive, but it’s something to watch out for.
Sleep is important, but so is exercise. If you enjoy exercising before bedtime, or if it’s the most convenient time to squeeze in a workout, don’t hold off due to concerns that it will interfere with your ability to get a good night’s sleep. You can go for that long evening jog, and catch your ZZZs too.
- Banno, M., Harada, Y., Taniguchi, M., Tobita, R., Tsujimoto, H., Tsujimoto, Y., Kataoka, Y. and Noda, A. (2018) Exercise can improve sleep quality: A systematic review and meta-analysis. PeerJ, 6:e5172; DOI 10.7717/peerj.5172.
- Myllymaki, T., Kyrolainen, H., Savolainen, K., Hokka, L., Jakonen, R., Juuti, T, Martinmaki, K., Kaartinen, J., Kinnunen, M.-L. and Rusko, H. (2011) Effects of vigorous late-night exercise on sleep quality and cardiac autonomic activity. Journal of Sleep Research, 20, 146-153.
- Stutz, J., Eiholzer, R. and Spengler, C. M. (2019) Effects of evening exercise on sleep in healthy participants: A systematic review and meta-analysis. Sports Medicine, 49, 269-287.
In the News
Provided below are a selection of articles from around the web on the issues associated with fatigue. We hope you find them useful and interesting.
Video: Can Exercise Improve Your Sleep?
PictureFit, YouTube, 30 September 2016
Want to Improve Your Sleep? Perhaps fall asleep quicker? How about just sleep longer? Find out how exercise can improve your sleep gainz!
Article: Physical Activity in the Evening Does Not Cause Sleep Problems
ETH Zurich, Science Daily, 18 December 2018
Even among sleep researchers, it is a widely held belief that sleep quality can be improved by avoiding exercise in the evening. However, as researchers from the Institute of Human Movement Sciences and Sport at ETH Zurich have demonstrated, it is not generally true.