The most obvious ways exercise contributes to your well-being is by helping you to maintain a healthy weight, good muscle tone and strong bones. But a regular exercise regimen does so much more than that.
For starters, consistent exercise is key to a healthy heart. Getting aerobic exercise helps lower blood pressure and cholesterol levels. And it reduces the odds of developing coronary heart disease, even in those with a family history.
In addition, regular exercise over a sustained period is great for the brain. It helps slow brain aging and provides protection from dementia. It can also help reduce your death risk by up to 45 percent.
If you have trouble sleeping, adding exercise to your daily routine can help with that as well. Committing to daily exercise can help you overcome insomnia and sleep more soundly if you stick to it. But if you want a good night’s sleep there’s one time of day you should avoid doing vigorous exercise.
Late-night exercise can be bad for sleep
Researchers at Concordia University recently reviewed data from 15 published studies to determine the impact of a single intense exercise session on healthy young and middle-aged adults in the hours before they go to bed.
Even though exercise can lead to better sleep, doing it at certain times of the day — like shortly before bedtime — can change the quality of sleep, according to the study.
“Overall, our analysis showed that when exercise ended two hours before bedtime, there were sleep benefits, including the promotion of sleep onset and increased sleep duration,” says lead author Emmanuel Frimpong, a postdoctoral fellow at the Sleep, Cognition and Neuroimaging Lab.
“On the other hand, when exercise ended less than two hours before bedtime, sleep was negatively impacted,” Frimpong adds. “It took longer for participants to fall asleep and sleep duration decreased.”
Researchers did note there was a combination of factors that enhanced or modulated the effects of exercise on sleep. They examined variables such as whether the participants exercised in the early or late evening, and how much time elapsed between the end of their workout and the time they went to bed. They also accounted for whether the participants were sedentary or physically active, as well as the intensity and duration of the exercises.
“When we reviewed the literature on this work, we found that there were a lot of mixed results,” says Melodee Mograss, a cognitive neuropsychologist and researcher at the PERFORM Sleep Lab. “Some depended on the time of exercise, others on the fitness level of a study’s participants, or even the type of exercise.”
Some evening exercises offer more benefit
For instance, the researchers discovered cycling in the hours before bedtime resulted in more favorable changes in sleep compared with running in the late evening.
According to the study data, late-evening cycling improved sleep onset and increased N3 stage sleep, the period during which the body heals and repairs itself. By contrast, running late in the evening made it more difficult for participants to enter the REM stage of sleep, the “dreaming” phase of sleep that’s believed to benefit learning, memory and mood.
Researchers say these differences are likely because running has more potential to cause exercise-related muscle damage and inflammation, both of which can affect quality of sleep.
Regardless of timing, high-intensity exercise overall contributed to a slight decrease in the REM sleep stage, the researchers note.
Pick a time and stick to it
“Based on our review, for healthy, young and middle-aged adults with no history of sleep disorders, evening exercises should be performed in the early evening if possible,” Frimpong says.
Given how important exercise is for good health, the best time for you to work out is whenever you can. However, when it comes to sleep quality, researchers stressed the importance of a consistent exercise schedule. Constantly switching your workout times from morning to evening — or even early to late evening — could cause disruptions to your sleep.
Other ways to ensure a good night’s sleep after exercising in the evening is to take a shower sometime between the time you stop exercising and the time you go to bed. It’s also important to avoid eating a heavy meal or drinking a lot of water right before bedtime.
Sources:
Intense workouts before bedtime won’t guarantee a good night’s rest, new research shows — Concordia University
The effects of evening high-intensity exercise on sleep in healthy adults: A systematic review and meta-analysis — Sleep Medicine Reviews
The Importance of Sleep and Understanding Sleep Stages — American Sleep Apnea Association
What is REM sleep? — Medical News Today