Does exercising at night harm your sleep?

Exercise isn’t just about strength. It’s about power, healing, and mental resilience. It’s about putting yourself - and your health - first.

Physical activity releases endorphins, increases longevity, and strengthens our vital organs. It can even combat sleep disorders such as sleep apnea. But with all that adrenaline pumping through our veins, could laying down to sleep after an intense bout of exercise do more harm than good? 

The best time to exercise: it’s personal

If you want to sleep better, there’s no blanket answer to the question of when to exercise. The truth is, the 'best’ time depends on a host of factors, including your age and health status.

Those at risk of high blood pressure, for instance, may see more improvements in their sleep quality and nocturnal blood pressure if they exercise in the morning.

Another consideration is your chronotype – whether you’re an ‘early bird’ or a ‘night owl’. There’s evidence that evening exercise negatively impacts sleep for early birds, but might not be so bad for night owls. Although this evidence is based on one small study and even the most nocturnal among us should avoid vigorous exercise at least four hours before bed. 

Lastly, consider your goals. If falling asleep earlier is the goal, it might make sense to exercise outdoors in the morning or afternoon, given that sunlight regulates our sleep-wake cycles. Exercising earlier in the day also stimulates the release of melatonin, helping us drop off more swiftly at bedtime.

But then again, it isn’t always practical to work out during the day…

The question of late-night exercise

You’re exhausted after a long day at work. There's hardly enough time to prepare dinner before tucking the kids into bed. You promised yourself a workout today, but so far it hasn’t materialised. If you squeeze one in before hitting the hay, won’t it ruin your sleep?

Research on the topic is complex and some evidence suggests that light night moderate-intensity exercise may not damage the quality of your sleep. But this is based on a small amount of research and we’re yet to understand the full implications of late-night exercise on sleep. Because exercise raises our core temperature, elevates our heart rate, and triggers the release of adrenaline, it’s best to avoid it at least four hours before bed.

How to combat exercise-induced sleeplessness

If you find yourself burning the midnight oil, avoid compromising your sleep by being mindful of the timing and type of exercise you do.

It’s best to stick to light-intensity exercise at least 1 hour before you plan to go to bed (ideally 90 minutes). Some examples might include:

• Yoga 

• Stretching

• Walking

And just to reiterate, avoid strenuous activity that skyrockets your heart rate at least four hours before bed, such as:

• High-intensity interval training (HIIT)

• Intense cardio e.g. spinning/sprinting

• Heavyweights/resistance training

The numan take

Don’t ignore the power exercise has on your mental resilience, physical strength, and even your sleep quality. But with all that adrenaline pumping through your veins, it’s best to get moving at least four hours before bed.