How Does a Workout Before Bed Affect Sleep?

Written By Alex Petrović

Sleep Consultant

13 November 2023 5 min read

Working out is generally always beneficial for your health, as long as you don't overdo it, but should you do your workout before bed? It might seem like a simple question to some, but there's actually quite a lot to take into account.

We've all heard how a good morning workout changed someone's life and allowed them to get into shape. However, you don't see as much discourse when it comes to late-night workout schedules.

So, today we're going to take a deep dive and see how working out before bed affects your sleep quality and whether you should reschedule your daily routine. And, of course, these are all going to be broad generalisations, as listening to your body is the only way to truly guarantee a good night's sleep.

How does exercise impact your sleep quality?

When done during the day, exercise has nothing but benefits when it comes to your overall health and your sleep. As long as you don't hurt yourself in the process or put too much strain on your body, you're all set to fall into a deep sleep.

However, things get a bit more complicated when it comes to evening exercise. Since it's usually in close proximity to your bedtime, it does in fact affect sleep and can lead to rather poor sleep hygiene. So, let's first look at the ways in which evening exercise might prevent you from getting quality sleep.

Raising your core body temperature

When you go to bed, your body temperature naturally drops as you slowly drift to sleep. Generally speaking, your body aims for a temperature of around 35-36 degrees Celsius before allowing you to fall asleep.

However, intense exercise can drastically heighten your body temperature, making it more difficult for your body to achieve this Goldilocks zone. This is especially true if you practice high-intensity exercise, like heavy weightlifting or intense cardio.

So, we recommend leaving at least a 90-minute window between finishing your workout and jumping into bed if you're not putting too much strain on your body. And if you're planning on high-intensity workouts, that window should be significantly larger – with 3-4 hours being the most optimal.

If you want to learn more about how temperature affects your sleep, we recommend reading our article on the ideal temperature for sleep.

Messing up your circadian rhythm

Your circadian rhythm is like a biological clock that tells your body when it's time to sleep and when you need lots of energy. For example, when sunlight enters your room, your circadian rhythm tells your body that it's daytime and that it's time to get up.

On the other hand, getting into a cool, dark room, covering yourself with a comfortable blanket and relaxing your muscles signifies that it's time to doze off.

So, you can hopefully see why late-night exercise throws a wrench into the system. Not only does your body go through stress, but if you're going to the gym, there's also loud music blaring accompanied by the sound of steel hitting the floor.

This isn't exactly the best signal to your body that it should go to sleep soon. Therefore, while an early morning workout might give you the energy boost to conquer the day, a late-night workout routine might leave you feeling energetic rather than sleepy.

Elevated adrenaline and cortisol levels

On a similar note as the previous section, vigorous exercise also raises your adrenaline and cortisol levels. And usually, when you hear adrenaline, you think “high-speed racing”, “non-stop action” or “life-threatening odds” and not “it's time to chill out and take a nap”.

Well, your body feels the same way. Cortisol isn't much better, as it's the stress hormone and even in healthy adults, heightened cortisol levels can make falling asleep a lot more difficult.

And if that wasn't bad enough, you'll also feel a spike in your metabolic rate, heart rate, and blood pressure. Which again isn't quite ideal.

Messing up your routine

We've already covered how workouts at night affect sleep on a physical level, but now let's talk about the mental aspect.

Having a consistent workout routine is essential to living a healthy life and it can improve sleep for the vast majority of people. But if you leave all your workouts for late at night, you might find it more and more difficult to actually stick to your schedule.

You might want to go out drinking with some friends or just get too engrossed in a series that you're watching and completely miss out on your workout. Or you might have had a really difficult day and you don't feel like you have the energy to go to the gym and give it your all.

This is why a lot of people work out first thing in the morning before any complications can arise. If you don't stick to your workout schedule, your overall health and sleep quality might suffer in the long run.

Then again, if you have ironclad discipline, this point doesn't really apply to your situation.

Are there benefits to evening exercise?

Now that we've covered the negatives of working out before bed, let's discuss some positives. After all, if it was so doom and gloom, you wouldn't see hundreds of people at the gym every night.

Eases pent-up stress

Although cortisol is secreted during your workout, you'll often find that you feel more at ease after getting a good workout in. All the pent-up stress you were holding onto during the day feels less heavy now or even disappears completely.

And nothing will usher you to sleep quicker than a feeling of bliss. So, instead of laying in bed and stressing over something that happened that morning, you can lull yourself to sleep and recount the PR you broke that day.

This is especially true if you do more relaxing forms of exercise – like yoga, mild jogging or moderate-intensity aerobic exercise. However, even with light or moderate-intensity exercise, we suggest giving yourself at least 90 minutes to cool off.

Improves sleep

Although you might've gotten the impression that we're strongly against working out before bed, that's not really the case. In fact, multiple studies conducted in 2019 and 2020 have found that working out can help you fall asleep faster and boost your overall sleep quality.

However, this only applies to light and medium-intensity exercises. That's because these same studies found that vigorous exercise before bed can in fact ruin your sleep quality and keep you awake if done too close to your bedtime.

On the other hand, moderate-intensity exercise performed quite well, showcasing positive results across the board. Not only that, it can help lessen some of the symptoms of sleep disorders such as obstructive sleep apnea. However, this isn't always the case.

So, as long as you're not vigorously running around or lifting heavy weights right before your bedtime, you can reap some benefits from your nighttime routine. Therefore, if you really want to work out close to your bedtime, just stick to aerobic exercise or something similar.

Easier to stay consistent

This might seem contradictory to what we said in the “messing up your routine” section, but it just depends on the type of person you are. For example, night owls might find it way easier to get a workout in during later hours of the day as that's when they naturally have more energy.

Plus, certain gyms might be less crowded during the evening, which is an extremely important fact for people who like to keep to themselves. And like we said before, anything that helps you keep up a healthy workout routine over the long run will greatly benefit your sleep.

So, as long as you don't jump into bed right after your workout, you should be getting better sleep before you know it!

The connection between sleep and working out

So far, it might've seemed like you had to make a choice – either prioritising your sleep or your gym routine. That's why in this section, we want to emphasise how important it is to have both sides of this puzzle.

We all know that physical activity and nutrition are the cornerstones of a healthy lifestyle. However, proper sleep is just as important as these two! After all, it's during rest that important processes like muscle recovery and growth take place.

And professional athletes are well aware of this. Roger Federer has gone on record to say that he spends half of the day sleeping in order to keep up his world-class performance. And while we can't suggest that everyone sleeps for 12 hours, this should showcase just how important proper sleep is!

The same could be said in the opposite direction as well – since a good exercising routine has been linked with better sleep quality countless times. So, better sleep = better workouts = even better sleep, and so on!

Things to consider when working out before bed

Now we're just going to go over some general pitfalls and things to look out for when working out before bed. We've already established that working out late has certain health benefits. So as long as you keep to the following tips, you should see an improvement in your sleep quality.

Intensity

As mentioned previously, high-intensity workouts are your enemy when it comes to late-night training. Intense physical activity will raise your body temperature and pump you full of adrenaline when you want to calm down and relax.

So, always try to prioritise low-intensity workouts if you plan on going to bed in the next few hours. Things like yoga, light jogging, and aerobic exercise will bring you the most good, as they also double as a relaxing bedtime routine.

Your usual sleep quality

In order to know where you're going, you need to be aware of where you are now. In other words, think about your sleep quality during nights when you don't work out at all. Does it take a long time to fall asleep? Do you feel energised? Do you feel stressed out during the night?

All of these questions are important as they should give you a rough idea of your current sleep hygiene. So, if you already have extra energy and feel tense at night, working out probably isn't going to net you better sleep. Rather you should either look into doing stretches or other activities that can calm you down or try having a consistent morning exercise routine to tire yourself out.

Lights

As mentioned when talking about the circadian rhythm, bright lights aren't something you want to experience right before going to bed. They will jolt your system and make you feel wide awake. And we've all seen how quickly turning on a bright light during the night can disrupt sleep.

So, if you normally work out at the gym, you might want to rethink your daily routine. After all, gyms are usually very well lit and even just the drive to the gym and back might completely ruin your circadian rhythm.

And if you're working out from home, try dimming down the lights and making the room more sleep-friendly. We're not saying you have to work out in the dark but do your best to avoid bright lights shining directly into your face.

As a bonus tip, try not to work out in your bedroom. The last thing you want is for your brain to associate the room where you sleep with stress, effort, and high energy levels.

Your diet

An often overlooked side effect of working out is how it affects your diet. After all, it's a lot easier to justify a cheat meal or snack if you just had a really good workout

And while normally that's completely fine, it's somewhat problematic when done so late in the day. Having a heavy or fatty meal can cause issues with digestion and keep you awake for quite a long time. This is because certain foods, just like high-intensity workouts, can signal your body to raise the core body temperature and secrete hormones like cortisol.

It is worth learning more about which foods you shouldn't eat before bed!

So, to summarise, doing a workout before bed has its pros and cons but it depends on different factors. Ideally, you want to leave yourself enough time between exercising and sleeping so your body can relax. If done correctly, working out can help you fall asleep every night. On the other hand, if it's too intense and close to your bedtime then it could have a knock-on effect. Plan your evening routine and sleep schedule to find what suits your lifestyle.

References & Resources

• Rise Science
• HealthLine
• The Empowered Athlete
• Rise Science
• HealthLine
• The Empowered Athlete

About the author

Alex Petrović

Sleep Consultant

As a former insomniac, I've learned the hard way the importance of good bedding products and sleep hygiene. So, I've studied to gain a diploma in Sleep Consultancy and continue to research to make sure you won't have to go through the same struggle. Hopefully, we can now all sleep soundly!