Is it a bad idea to do a challenging interval session too close to bedtime?
It may affect your sleep because it raises the levels of stress hormones such as adrenaline, noradrenaline and cortisol. These hormones are produced as part of the ‘fight or flight’ response in preparation for action. Late exercise could leave these hormones circulating when you should be winding down. Also, cortisol levels normally naturally decrease as the day goes on, but intense exercise will raise levels. Endorphins released by a workout could be buzzing around, too.
I rarely do late-evening sessions now, as they don’t fit well with family life. But when I was younger I did practically all my interval sessions late. I felt very tired afterwards, especially after refuelling. I used to think I would sleep well but after a while I would find it very difficult to sleep. If your sleep is affected try to have at least three hours between finishing your workout and going to bed. Try not to rely too much on stimulants – such as caffeine – before the session, as this could make it tougher to get to sleep afterwards. After your workout eat a nutritious meal that has a good portion of carbs, make sure you are well hydrated and cool your body temperature before bed. Stretch before bed, too, to take tension out of your muscles. Remember, though, that people who exercise regularly tend to sleep better than those that don’t.
TIMING IS EVERYTHING Exercise will help you sleep, but don’t do it right before you hit the hay.