How Exercise Affects Your Sleep
Sleep and physical exercise are both important. So, how does exercise affect sleep and vice versa? We asked a group of experts to find out
Sleep has become something of a hot topic in recent years. And it seems that we could all be doing more to improve our precious hours of shuteye.
There is plenty of information out there about how to improve your sleep, ranging from keeping to consistent sleep and wake-up times, to getting morning sunlight exposure and ensuring that your bedroom is kept dark and quiet.
But where does exercise fit into the sleep equation? Does exercise during the day have a significant effect on sleep at night?
Editor's note: The content on this website is meant to be informative in nature, but it should not be taken as medical advice. The content of our articles is not intended for use as diagnosis, prevention, and/or treatment of health problems. Always speak with your doctor or a certified medical professional before making any changes to your lifestyle, diet or exercise routine, or taking any supplements.
As you may have already guessed, being physically active during the day has regularly been linked with better sleep quality.
“The scientific literature consistently shows that those who engage in high levels of physical activity have a greater sleep duration and percentage of slow-wave (deep) sleep than individuals who are less active,” explains Peter Walters, Professor of Applied Health Science at Wheaton College.
For example, this meta-analysis of 44 studies examined the relationship between exercise and sleep, and it concluded that those who exercise regularly experience an increased need for total sleep time, amongst other things.
However, this is not the whole story. The link between exercise and sleep appears to be a two-way street. In other words, physical exercise during the day may help you to sleep better, but it’s also widely accepted that good sleep will help you to perform better during exercise.
To delve a little deeper, we asked a select group of experts for their thoughts on the link between exercise and sleep.
Here’s what they said.
Being A Couch Potato Is Bad For Your Sleep – But Avoid Working Out Late At Night
Michael K. Scullin, Ph.D., Associate Professor of Psychology and Neuroscience at Baylor University
There’s certainly some evidence that sleeping better allows you to run farther, serve more aces, and hit more free throws.
What’s often is missed is the “mental side” of athletic performance, which is even more strongly influenced by sleep. When you’ve been cutting back on sleep, you’re moodier and have greater difficulty regulating your emotions, particularly when things are going badly.
In other words, after five hours of sleep, you’ll probably feel less motivated and be more willing to quit sooner than after eight hours of sleep.
And, let’s not forget about the importance of sleep for sustaining focus. If there’s one thing we know without a shadow of doubt about sleep deprivation it’s that if you’ve cut back one hour, two hours, three hours or so forth, you’re going to have more lapses of attention. Your mind will wander more, you may miss something right before your eyes, and you’re more likely to make silly mistakes.
Being a couch potato is bad for your sleep quality. But that doesn’t mean that all types of exercise benefit your sleep.
If you work out late at night, it can impair your sleep because either your heart rate stays elevated too long (making it difficult to fall asleep) or you consume too little or too much water afterward, causing you to wake in the middle of the night.
It’s therefore advised that you work out in the morning or early afternoon.
Lastly, get some exercise outside! People do not realize how important natural sunlight is to setting your internal clock, which allows you to feel alert during the day and sleepy during the night.
So get more natural sunlight, particularly in the morning hours, and you may find that life improves.
The Psychological Benefits Of Exercise Can Help To Support Better Sleep
It may be surprising to think that something as invigorating as exercise could help you with something as calming as your sleep and that sleep can help you with your exercise too.
Yet, quality empirical research over the years clearly indicates that exercise and sleep are indeed related and in helpful, synergistic and in both direct and indirect ways.
For example, laboratory research over many years (including in my laboratory at Santa Clara University) has found that exercise helps to improve mood, such as reducing mild to moderate anxiety, depression, and perceived stress while improving self-confidence.
These helpful psychological benefits are available even when engaging in moderate intensity exercise. Thus, talking a pleasant walk or jog is OK and you do not necessarily have to be a “gym rat”, as they say, to achieve these benefits.
These exercise-induced improved moods then helps us to sleep better since it is these common negative moods that often contribute to sleep difficulties.
Stress, anxiety, and depression are commonly associated with sleep problems and so if exercise can better manage these moods then you will likely sleep better.
Additionally, regulation theory informs us that the more dysregulated we are in one important area of living such as exercise, diet, sleep, and relationships, the more dysregulated we will be in other areas too. So, sleep or exercise dysregulation will likely impact each other.
One important caveat to the exercise and sleep relationship however, is that rigorous and activating exercise too close to bedtime will likely make sleep more difficult and so exercise should be completed earlier in the day long before you go to bed.
So, taking a late night fitness class or going for a long run after dinner is likely not a great idea.
Exercise And Sleep Have A Bidirectional Relationship
Kristi Chaussard, Founder and Pilates Trainer at Gone Adventuring
Exercise has long been proven to improve sleep quality. This link has been verifiably established by a large amount of research from numerous sources, including Johns Hopkins University, Stanford doctoral researchers, and countless other scientists.
A recent systematic review of sleep and exercise-related studies published between 2013 and 2017 found that all but five studies demonstrated a positive correlation between exercise and improved sleep quality. And not only does exercise bolster your sleep duration and quality, but it also may help prevent excessive daytime sleepiness.
Conveniently, you don’t have to spend hours in the gym to reap the rewards of exercise. In fact, the systematic review showed that sleep duration and quality improved no matter the mode or intensity of the physical activity.
While another study suggests that moderate exercise is better for sleep than high-intensity exercise, it’s important to remember that some exercise is usually always better than no exercise at all.
So, get your workout in today! Even if it is only 10 to 15 minutes, move intentionally, mindfully, and get your blood flowing. Exert yourself and use your core.
Because exercise and sleep feed off each other in a bidirectional relationship, any exercise helps improve your quality sleep at night and ability to feel rested during the day, and vice versa!
Better yet, it doesn’t take months of exercising consistently for your sleep to improve – you could see a difference in your sleep the very day you exercise.
Too Much Exercise May End Up Being Detrimental
Olivier Poirier-Leroy, Former National Level Swimmer and Founder of Yourswimlog.com
As a former national level swimmer, there were days where I’d come home after five to six hours of hard training and be physically destroyed, and yet, be unable to fall asleep at night.
I never quite understood why this was, but when you think about the fact that physical exercise is a form of stress, and that intense exercise requires up to 48 hours to rebalance hormones (including adrenaline and insulin), you can start to see how overtraining and excessive exercise can cause problems at night.
One study with elite female competitive swimmers found sleep disturbances were at their peak when training was at its hardest, showing that working hard at the gym or pool will help you sleep, but only up until a point.