Working out before bed — does it impact your sleep?

Good things come in pairs: sun and sand, warm cookies and milk, and a treadmill and phone loaded with your favorite songs. One such pairing with a similar reciprocal relationship is exercise and sleep. The two practices complement each other, but their interactions are affected by factors like the type of workout you're doing, the intensity of your exercise and the time of day that you break a sweat. This raises the question: When should you exercise to enhance a good night's rest?

Some research says that you should exercise in the morning or during the daytime so your body has time to cool off and not be "revved up" before it's time to lie down. However, other studies support working out in the evening because muscles follow circadian rhythms, with muscle strength and some metabolic markers peaking later in the day. So the question becomes, if you want to work out before bed, how can you do it in a way that's supportive to your body's sleep needs and your personal fitness goals?

Exercising before bed: It's a nuanced decision

When it comes to sleep and exercise, it's important to remember that everyone is unique — you have your own circadian rhythms that guide your natural sleep-wake cycle and your own habits, interests and schedule to contend with. As such, there's no hard-and-fast rule when it comes to the best time of day to exercise without interrupting your sleep. Most fitness experts will tell you, the best time for exercise is the time you'll actually do it. So if that means lacing up your kicks at 6 a.m. or 9 p.m. because it's the only time you can carve out for a quick jog, that's going to be the best decision for you.

That said, if you have the flexibility to tailor your workout program to enhance your sleep (and your fitness), there are a few things science tells us about getting the timing, type and intensity of your exercise program right. But even with science on our side, some of the information is conflicting and doesn't entirely take into account individual differences. All in all, it's important to consider what the science tells us and use it to inform your exercise decisions, not dictate them.

Science that supports exercising before bed

Whether you prefer to sleep in and forgo morning gym sessions or you have significant daytime obligations, ample research suggests nighttime exercise offers a number of benefits.

Evening exercise may enhance performance, particularly for strength training

Your body's core temperature rises throughout the day and into the late afternoon and early evening. Studies consistently report greater maximal strength output is seen in the late afternoon (between 4 p.m. and 8 p.m.), correlating with this rise in internal body temperature and what appears to be intrinsic gene expressions in muscle cells related to circadian rhythms.

Conversely, maximal strength is lowest in the early morning hours when internal body temperature is also at its lowest and the circadian muscle cell gene expressions are fewer. For anyone looking to build strength and take advantage of peak maximal muscle force, a late afternoon or early evening training session is likely ideal.

However, it's important to note that circadian rhythms vary from person to person, with some people displaying an "earlier" chronotype and others displaying a "later" one. For individuals with an earlier chronotype (think: your "morning lark" types), exercise performed later in the day may be more likely to disrupt circadian rhythms, blunting the potential advantages of afternoon or evening workouts and making it harder to fall asleep.

Also, while evening workouts may technically be best for maximizing your natural muscle force and strength, that doesn't mean you're missing out if you have to strength-train earlier in the day. There's evidence to indicate that with a proper warmup before exercise, you can even the playing field (so to speak) and experience the same level of strength output as if you were exercising later in the day.

Evening exercise may support weight loss and metabolic health

To be clear, the research on this subject is new and recent, but multiple recent studies indicate that afternoon or evening exercise may be more effective than morning exercise in improving how your metabolism functions (although one study refutes this). Possible benefits include improved glycemic control (how your blood sugar levels fluctuate), decreased blood pressure and improved lipid (cholesterol) profiles. This is likely linked to the changes in circadian-driven gene expressions in the muscle tissues that take place later in the day.

However, morning exercise may help with appetite regulation more than evening exercise, which could help improve energy balance, which also ultimately supports weight loss.

Evening exercise may improve sleep in individuals who struggle with sleep

While research on whether exercise before bed is hurtful or helpful to subsequent sleep is varied (more on that in a minute), multiple studies indicate that evening or nighttime exercise can actually improve sleep outcomes for individuals who tend to have more trouble sleeping.

To be clear, exercise as a whole (independent of the time of day it's performed) has been proved to improve sleep and reduce sleep disturbances. So regardless of when you decide to work out, chances are your sleep habits and patterns will benefit.

That said, one 2020 study found that low-intensity cardiovascular exercise performed in the evening by older adults (a group that tends to have greater problems with sleep disturbances) was more effective at improving overall sleep than the same low-intensity exercise performed in the morning. A separate study found that sleep improvements with moderate-intensity evening exercise were most prominent in young adults with trouble sleeping than in individuals who weren't as likely to experience sleep disturbances.

Furthermore, a small study of families with young children (2 to 5 years old) found that an evening family yoga routine was more effective in encouraging sleep and reducing household chaos than a more traditional bedtime story routine. While this study applied to young families, the calming effects of low-intensity exercise apply to other groups too. "Calming exercises like yoga or stretching can help you prepare for sleep," says holistic therapist Cheryl Groskopf, LMFT, LPCC. "This is because yoga activates the parasympathetic nervous system, which helps your body relax."

Science that refutes exercising before bed

If you find that exercising in the evening disrupts a good night’s sleep, you're not alone. This may be related to whether you're a natural morning person or night owl, but it could also be tied to the intensity of the exercise you're performing or how close to bedtime you're breaking a sweat.

Exercise raises body temperature and "wakes up" your body's systems

The very nature of exercise is that it excites your body's systems — it gets your heart pumping, your blood flowing, your muscles moving and your brain working. All of these factors also work to raise your core body temperature, which is the exact opposite of what needs to happen to help you fall asleep.

In fact, your body's core temperature needs to drop in the evening to facilitate a good night's rest. That's why some studies and experts advise against exercising vigorously right before bed.Dr Farhan Malik, a board-certified sports medicine physician practicing in Georgia, advises against vigorous exercise before bedtime. "Exercise elevates core body temperature and arousal, which can make it difficult to fall asleep if done too close to bedtime."

That said, studies indicate that if you allow at least 90 minutes to cool down after your workout before you try to sleep, your sleep quality is largely unaffected by nighttime exercise. This is particularly true for low to moderate-intensity workouts (like going for a walk or doing gentle yoga), but even high-intensity routines are unlikely to cause a major sleep disruption if you allow sufficient time (between 2 and 4 hours) to cool down before bed. In fact, some studies indicate that core body temperature is likely to lower to pre-exercise levels in just 30 to 120 minutes postworkout.

How to exercise before bed in a way to support good sleep

If you do want to work out close to bedtime, these tips can help you put this choice into action.

Try a lower-intensity workout

If you find that a late night jog or strength training session is interfering with your ability to settle down and fall asleep, you may want to skip the more intense routines and opt for something a little more low-key. Gentle yoga practices, tai chi or a neighborhood stroll can all still offer benefits of exercise without raising your core body temperature excessively or exciting your nervous system as much as more intense exercise routines.

Allow time to cool down

Chances are if you're having a hard time falling asleep after your nighttime workout, it's because you're not giving your body enough time to cool down. While some research indicates that 30 minutes is sufficient to allow your body to reset, most experts recommend more time between your fitness routine and bedtime. "If you are going to partake in physical activity before bed, it should take place at least two hours before you lay down," says Josh York, CPT, founder and CEO of Gymguyz, He says this allows your body time to calm and cool down and for endorphins to flush out, "so you are not having a restless night."

Remember to optimize your sleep environment

To help ensure a better night's rest, it's important to optimize your sleep environment. Sleeping in a cool, dark room without ambient light or distractions from noise or technology is best. Consider investing in tools like blackout curtains, sleep masks, white noise machines, cooling fans or cooling sheets to help maximize your sleep hygiene. Even if you're still a bit revved up after a nighttime workout, lying down in a space that's prepped for sleep will help signal to your body that it's time to slow down and drift off.

When's the best time of day to exercise for better sleep?

Ultimately, once again the best time to workout is the time you'll actually do it. If you prefer a late night routine, it's unlikely to interfere with your sleep (and may actually help it), as long as you pay attention to our tips above. In fact, you may enjoy some performance- and health-enhancing benefits if you elect to break a sweat in the late afternoon or evening.

That said, if late night workouts just don't work for you, you can feel good about exercising in the morning or daytime, both of which support high-quality sleep. It's a personal choice that should be driven by your preferences and schedule rather than the interesting but somewhat convoluted science on the subject.

FAQs

Is it bad to exercise before bed?

In a word, no. While the science is mixed on exercising before bed, as long as you're smart about how you go about it, a nighttime workout is unlikely to negatively impact your sleep. Remember, exercise provides significant health benefits, and working out before bed is better than not working out at all. Just make sure you allow sufficient time to cool down between your workout and your bedtime.

Does working out before bed burn more fat?

It could, but the results are mixed. Some studies indicate that morning workouts facilitate fat loss while other studies indicate better metabolic outcomes with afternoon or evening workouts. Ultimately, you'll have greater results by finding a time of day to exercise that you can stick with long-term. Consistency in exercise is always what facilitates the most significant fat loss or weight loss results.

What exercise is best before bed?

This ultimately depends on your own internal clock and how much time you allow yourself to cool down between your workout and your bedtime. If you plan to exercise immediately before falling asleep, gentle yoga and slow-movement exercise, such as tai chi, can help your body relax without increasing your core body temperature too much. These forms of exercise lower stress and prepare your body for rest. That said, if you plan to allow a few hours between your workout and your bedtime, there's evidence to indicate that even vigorous exercise, like running or high-intensity interval training is unlikely to make it harder to fall or stay asleep.

Meet the Experts

• Cheryl Groskopf, LMFT, LPCC, holistic therapist practicing in California

• Farhan Malik, MD, board-certified sports medicine physician practicing in Georgia

• Josh York, CPT, founder and CEO of Gymguyz in New York