Content Reviewers:Rishi Desai, MD, MPH
Insomnia affects about a third of all people at some point in their life and it makes it difficult to either fall asleep or stay asleep.
Sometimes it’s a mild, short-term symptom but if it’s severe and lasts a long time it’s considered a disorder.
Either way, it leaves the person feeling exhausted. Unfortunately, treating insomnia is challenging.
For example, sleep medications often have dangerous side-effects and can be habit forming, so they’re generally recommended for temporary use only after other options have been tried.
Another treatment is cognitive behavioral therapy, which is effective, but requires clinical supervision which costs time and money.
This is where exercise comes in.
Exercise is safe, can be done quickly and cheaply, and doesn’t require the help of a highly trained clinician.
Also, exercise has been shown to improve sleep quality in a number of studies, and that’s why exercise is a core recommendation from the National Sleep Foundation to improve sleep.
That said, while there are a number of clear benefits to exercise, only a few studies have looked at the relationship between physical exercise and insomnia, so whether or not exercise improves sleep for people with insomnia remains unclear.
They specifically looked at randomised clinical trials, where at least 30 minutes of either aerobic exercise, like cycling, or mind-body exercise, like yoga or Tai chi, were done per session, for at least 120 total minutes a week for several weeks, to see if that improved overall sleep in adults with insomnia.
To measure sleep quality, the studies either used subjective data, like questionnaires and diaries or objective data, like actigraphy, which measures body movement through the night, or polysomnography, which measures brain waves, heart rate, and breathing through the night.
So what did they find? Well, let’s start with studies on individuals with mild or short-term insomnia symptoms.
Four out of five studies that used subjective data, found that exercise improves sleep while the fifth study showed no difference between the exercise and the control group.