YOU NEED TIME TO RECOVER
Exercising at any other point is fine, but working out 90 minutes before sleeping isn’t the greatest. On the sleep perspective, Sleep.org has stated that your body and mind need at least 90 minutes to cool down from strenuous activities or workout. So things like an aerobic workout isn’t good for you that late as those exercises are designed to boost your energy levels and increase endorphins.
Even if those things are helpful for our overall health, they’re not ideal when we’re trying to fall asleep.
Sleep specialists have also chimed in about this and noted that exercising also gives us a jolt of energy through the hormone cortisol. It’s a hormone that’s great in increasing our energy levels, though it’s clearly not helpful when trying to get great sleep, since it promotes waking up or staying up.
Overall, if you exercise too close to your bedtime, you’ll risk having higher levels of blood cortisol, which will make it harder to fall asleep and stay asleep too.
It’s such a common occurrence that sleep scientists have a name for it: runner’s insomnia. Note that this isn’t exclusive to just running.