Insomniacs are commonly told to get more exercise. But spending 45 minutes on the treadmill one day won’t actually help you sleep better that night, according to a new study.
The findings run counter to at least some other studies that suggest exercise significantly improves the sleep of people with chronic insomnia.
But the new Northwestern Medicine® research shows that aerobic exercise during the day does not result in improved sleep that same night when people have existing sleep troubles.
“If you have insomnia you won’t exercise yourself into sleep right away,” said lead study author Kelly Glazer Baron, a clinical psychologist and director of the behavioral sleep program at Northwestern University Feinberg School of Medicine. “It’s a long-term relationship. You have to keep at it and not get discouraged.”
Baron told Huff/Post50 that the study demonstrates how exercise doesn't lead to better sleep immediately in insomniacs, even though other studies have found that it does in healthy individuals.
"When people begin to exercise in an attempt to improve sleep, they need to keep in mind the big picture. It's so easy to focus on the day-to-day effect, and it could be discouraging to look at it that way," she said. "In many ways, it's like weight loss. It is not instant gratification!"
Baron's research also showed that people exercise less after a night of poor sleep. "Sleeping poorly doesn’t change your aerobic capacity, but it changes people’s perception of their exertion,” Baron said. “They feel more exhausted.”
The study, published in the Journal of Clinical Sleep Medicine, looked at daily sleep data from 11 women ages 57 to 70 over the course of six weeks. Baron believes the results can be applied to men because "we haven't seen gender differences in responses to other behavioral treatment for insomnia. But we would have to study it for sure."
Baron said she decided to analyze the daily effect of exercise after hearing her patients with insomnia complain the exercise she recommended didn’t help them right away.
“They’d say, ‘I exercised so hard yesterday and didn’t sleep at all,’” she said. “The prevailing thought is that exercise improves sleep, but I thought it probably wasn’t that simple for people with insomnia.”
The takeaway, according to Baron, is that people need to be persistent with their exercise routines.
“People have to realize that even if they don’t want to exercise, that’s the time they need to dig in their heels and get themselves out there,” Baron said. “Write a note on your mirror that says ‘Just Do It!’ It will help in the long run.”
A recent poll of 1,000 people conducted by the National Sleep Foundation found that those who identify themselves as exercisers report better sleep than those who consider themselves non-exercisers.