Chronic insomnia, defined as difficulty initiating or maintaining sleep, awakening too early in the morning, or nonrestorative sleep, is the most common sleep disorder among adults. Though exercise has long been assumed to improve sleep, surprisingly little research has been conducted on the effect of exercise on chronic insomnia.
Of the handful of studies that have been performed, they suggest that exercise significantly improves the sleep of people with chronic insomnia. The only study that looked at the effects of a single exercise session found that a bout of moderate-intensity aerobic exercise (e.g., walking) reduced the time it took to fall asleep and increased the length of sleep of people with chronic insomnia compared to a night in which they did not exercise. However, in the same study, vigorous aerobic exercise (e.g., running) or lifting weights did not improve sleep. Similar results have been found for studies that examined the effects of long-term exercise on sleep in adults with insomnia. In these studies, after 4 to 24 weeks of exercise, adults with insomnia fell asleep more quickly, slept slightly longer, and had better sleep quality than before they began exercising.
Although the exact mechanisms are unknown, there are many possibilities for how exercise may reduce insomnia severity. One way may be by the body-heating effects of exercise, especially when performed in the afternoon or later. Exercise triggers an increase in body temperature, and the post-exercise drop in temperature may promote falling asleep. Exercise may also reduce insomnia by decreasing arousal, anxiety and depressive symptoms. Insomnia is commonly linked with elevated arousal, anxiety, and depression, and exercise has strong effects on reducing these symptoms in the general population. Finally, exercise may reduce insomnia by its effects on circadian rhythms (body clock). For people with insomnia due to the timing of their body clock, exercise may shift its timing depending upon the time exercise is performed.
We still need to learn much more about the relationship between exercise and chronic insomnia. For instance, we do not know how exercise compares to other insomnia treatments, especially sleep medications. We also know little about what types of exercise improve sleep the most, how much exercise is needed to improve sleep, and what time of day is best for exercise to improve sleep in people with insomnia. However, from the available evidence, exercise does hold great promise for improving the sleep of those with chronic insomnia.
The current recommendation is that regular moderate exercise, such as swimming or walking, can help relieve some of the tension built up over the day. Make sure that you don’t do vigorous exercise, such as running or the gym, too close to bedtime, though, as it may keep you awake.
Try following these other tips for a more restful night:
1. Keep regular sleep hours
Going to bed and getting up at roughly the same time every day will programme your body to sleep better. Choose a time when you’re likely to feel tired and sleepy.
2. Create a restful sleeping environment
Your bedroom should be a peaceful place for rest and sleep. Temperature, lighting and noise should be controlled so that your bedroom environment helps you to fall (and stay) asleep.
If you have a pet that sleeps in the room with you, consider moving it somewhere else if it often disturbs you in the night.
3. Make sure your bed is comfortable
It’s difficult to get restful sleep on a mattress that’s too soft or too hard, or a bed that’s too small or old.
4. Cut down on caffeine
Cut down on caffeine in tea, coffee, energy drinks or colas, especially in the evening. Caffeine interferes with the process of falling asleep, and also prevents deep sleep. Instead, have a warm, milky drink or herbal tea.
5. Don’t over-indulge
Too much food or alcohol, especially late at night, can interrupt your sleep patterns. Alcohol may help you to fall asleep initially, but it will disrupt your sleep later on in the night.
6. Don’t smoke
Nicotine is a stimulant. Smokers take longer to fall asleep, they wake up more frequently, and they often have more disrupted sleep.
7. Try to relax before going to bed
Have a warm bath, listen to quiet music or do some gentle yoga to relax the mind and body. Your doctor may be able to recommend a helpful relaxation CD.
8. Write away your worries
If you tend to lie in bed thinking about everything you have to do tomorrow, set aside time before bedtime to make plans for the next day. The aim is to avoid doing these things when you’re in bed, trying to sleep.
9. If you can’t sleep, get up
If you can’t sleep, don’t lie there worrying about it. Get up and do something you find relaxing until you feel sleepy again, then go back to bed.
If lack of sleep is persistent and affecting your daily life, make an appointment to see your GP.
Guilleminault C, Clerk A, Black J, Labanowski M, Pelayo R, Claman D. Nondrug treatment trials in psychophysiologic insomnia. Arch Intern Med. 1995;155(8):838-44.
Horne JA, Staff LH. Exercise and sleep: body-heating effects. Sleep. 1983;6(1):36-46.
Passos GS, Poyares D, Santana MG, D’Aurea CV, Youngstedt SD, Tufik S, de Mello MT. Effects of moderate aerobic exercise training on chronic primary insomnia. Sleep Med. 2011;12(10):1018-27.
Passos GS, Poyares D, Santana MG, Garbuio SA, Tufik S, de Mello MT. Effect of acute physical exercise on patients with chronic primary insomnia. J Clin Sleep Med. 2010;6(3):270-275.
Reid KJ, Baron KG, Lu B, Naylor E, Wolfe L, Zee PC. Aerobic exercise improves self-reported sleep and quality of life in older adults with insomnia. Sleep Med. 2010;11(9):934-40.