Regular exercise is associated with less insomnia, study shows

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Tired from a restless night spent awake? One of the most helpful things to do might be to get some exercise, according to a new study.

“Physically active people have a lower risk of insomnia symptoms and extreme sleep duration, both long and short,” said lead study author Dr. Erla Björnsdóttir, sleep expert and part time teacher and researcher at Reykjavik University.

The study published Tuesday in the journal BMJ Open looked at data from more than 4,300 people ages 39 to 67 over a 10-year period.

Björnsdóttir is affiliated with a sleep application that tracks sleep and gives tips and resources for better sleep. The company didn’t fund this study, and the authors didn’t report any competing interests.

Participants in nine European countries were surveyed about their frequency, intensity and duration of physical activity as well as their symptoms of insomnia, amount of sleep each night and feelings of sleepiness during the day.

Those who were persistently active were 55% more likely to be normal sleepers – those who sleep 6 to 9 hours a night –  and those who became active over the time period were 21% more likely to sleep normally – after adjusting for age, sex, body mass index (BMI) and smoking history, the study said.

The results are strong on their own but are also supported by an existing body of literature, said Dr. David Neubauer, associate professor in the department of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine. He was not involved in the research.

“Our results are in line with previous studies that have shown a beneficial effect of physical activity on symptoms of insomnia, but the current study additionally shows the importance of consistency in exercise over time,” Björnsdóttir said in an email. “It therefore matters to be physically active throughout your life in order to reduce the risk of insomnia and short sleep duration.”

The study may give health care professionals another tool alongside medication and therapy, said Dr. Shalini Paruthi, codirector of the Sleep Medicine and Research Center at St. Luke’s Hospital in Chesterfield, Missouri, and an American Academy of Sleep Medicine spokesperson. She was not involved in the research.

“It gives us an idea of something that maybe we don’t always think about for treatment of insomnia,” Paruthi said.

There are plenty of reasons why physical activity may help in getting a good night’s rest.

“Exercise has been shown to improve sleep quality and duration by promoting relaxation, reducing stress, and enhancing mood. Physical activity helps regulate the body’s internal clock and promotes deeper, more restorative sleep,” Björnsdóttir said.

This study does not show on its own that adding in exercise will reduce insomnia symptoms, since it did not get a clear baseline of sleep quality before activity was added in, Neubauer said.

However, there is still good evidence out there.

“There is some literature suggesting … people who start becoming more physically active and exercising more do have a tendency to have improved nighttime sleep in terms of their total sleep time, and their ability to fall asleep,” he said.

It’s important to note, however, that people who have long had problems with insomnia likely won’t find that exercise completely cures their condition on its own, Paruthi added.

And it will vary individually — some people will see amazing results, others moderate and a group of people may not see any improvement, she said.

Cognitive behavioral therapy for insomnia is the most effective tool out there for treating insomnia, so people with more severe sleep problems may want to seek that out as well, Paruthi added.

You don’t have to start running marathons to get the benefit. You just have to start, the experts said.

“Even moderate-intensity exercise, such as walking or yoga, can have significant positive effects on sleep,” Björnsdóttir said.

Paruthi has seen from her patients that there are always roadblocks to getting more active, but that any amount helps.

“Even if you can only walk two houses to the left, come back and walk two houses to the right – that’s a great start,” she said. “Even if you’re doing five minutes a day, you just have to start somewhere.”

If you want to make your activity even more helpful to your circadian rhythm, you can get outside in the sunlight, Neubauer said.

“Both being outdoors and being physically active can have a positive effect on our circadian rhythm. And it is our circadian rhythm that promote sleep at nighttime and alertness during the daytime,” he said.

“The degree to which people can modify their lifestyles to enhance activity and being outdoors and getting more light  certainly has the potential to have a positive effect on nighttime sleep.”