To capitalise on the sleep-enhancing benefits of exercise, it’s important to first consider what triggers sleep. Our body temperature naturally rises during the day before coming back down at night, and this decreasing temperature appears to be an important trigger, signalling that it’s time to sleep. So how can we maximise this for a good night’s sleep? There are two things to consider – exercise timing and exercise type.
If we perform exercise too close to bedtime, we run the risk of increasing body temperature too much (as well as releasing adrenaline), which may delay sleep. Therefore, the best time to exercise would be around five to six hours before going to bed – in this way you will be going to sleep at the same time your body temperature is decreasing.
However, the type of exercise can also play a part. While resistance training is beneficial, cardiovascular exercise appears to strongly promote sleep-enhancing benefits. This is down to the fact that while cardiovascular exercise keeps body temperature higher for several hours after exercise, it then drops lower than if you hadn’t exercised. When this is timed to your sleep cycle, it may result in a better night’s sleep.
When it comes to choosing the type of cardiovascular exercise – keep it simple. 20-30 minutes of any aerobic activity in which heart rate is up and your muscles are pumping continuously is sufficient to keep body temperature up for several hours afterwards. This in turn will activate cooling mechanisms to help facilitate sleep.