How Does Exercise Affect Sleep?
Could something as simple as more exercise be the elixir that cures your sleep disorder? Chances are no, more exercise will not cure your insomnia. However, regular physical activity does improve sleep for most people.
How exercise helps with sleep
For all people, regular exercise helps with sleep. There are several reasons for this:1
- Exercise, especially in the morning or afternoon, raises body temperature. When you cool back down, it may trigger drowsiness and help you fall asleep.
- Outdoor exercise exposes you to sunlight, which helps your body maintain its circadian rhythms, or sleep-wake cycle.
- Another theory is that exercise requires the body to use up energy and muscle that then needs to be restored during sleep.
The relationship between exercise and sleep is complicated. A 2013 study asked a group of women to exercise for 30 minutes, 3 times a week. The doctors found that it took several weeks of regular exercise for the women’s sleep to improve. After 4 months, the women were getting 1 hour and 15 minutes more sleep than before. They also found that a lack of sleep had an immediate impact on how much exercise the women got the next day.2
How exercise impacts sleep disorders
Exercise may be even more important if you have a sleep disorder. However, how exercise impacts your sleep can depend on which type of sleep disorder you have.
For people with insomnia, exercise helps reduce the amount of time it takes to fall asleep, improves sleep quality, and reduces depression and anxiety. A 2010 study looked at adults 55 and older with insomnia who did not exercise regularly. The people who began exercising for 30 minutes, 3 to 4 times a week, slept longer and reported more restful sleep, improved mood, and better quality of life.3-4
For people with sleep apnea, exercise can lead to weight loss, which often improves sleep quality. In fact, the link between obesity and sleep apnea is so strong that weight loss is often one of the first treatments doctors recommend. Studies have found that even losing a few pounds can reduce the severity of sleep apnea. And, exercise can improve sleep apnea, even without weight loss.5
For people with narcolepsy, being overweight or obese is common. This may be because the brain changes that cause narcolepsy also slow metabolism. Regular exercise can lower blood pressure and reduce weight, both of which can improve the overall health of someone with narcolepsy.6
Restless legs syndrome
For people with restless legs syndrome (RLS), studies show a clear connection between more exercise, reduced RLS symptoms, and better sleep. Doctors are not sure why exercise helps reduce RLS symptoms. However, both scientific studies and personal reports show that exercise helps reduce leg twitches, pain, and crawly sensations.7
In general, people with sleep disorders tend to be overweight or obese, for complex reasons that doctors do not completely understand. They do know that exercise improves heart health and mood, and helps you lose weight or keep weight in check, which are always good outcomes.7
That said, many studies show that how well exercise improves sleep can be different for younger people, people who are already fit, or people with additional health conditions.8
How much exercise do you need to sleep better?
In general, doctors recommend you get 150 minutes of exercise each week. That means you should walk, swim, or bike about 30 minutes a day for 5 days out of the week. However, even a 10-minute walk each day can help you sleep better. Studies show that it often takes several weeks of regular exercise to see sleep improvements.1,7
When should you exercise to sleep better?
Morning or afternoon exercise gives your body time to cool down and relax so that you can fall asleep. Vigorous evening exercise is not recommended because it stimulates the body and does not give you time to slow down and feel sleepy.1
Exercise also causes the body to release endorphins, those brain chemicals that make you feel better. Endorphins also energize you, so exercising at least 1 to 2 hours before bedtime allows the brain time to process the endorphins exercise releases.9