Hit the Sack

“Sleep is good.”

This seemingly simplistic statement was made by my astrophysicist roommate in college when I asked him why he napped so frequently. Twenty years later I revisit this quote as I ponder and study the virtuous circle that links exercise and sleep.

Simply put, the more you exercise during the day, the sleepier you’ll be in the evening, thus falling asleep faster and achieving a better quality sleep (all other things being equal). During this post-exercise sleep cycle, your muscles recover faster and stronger than they would have normally and your energy supply is recharged faster.

What kind of exercise promotes sleep? There are a few items that we need to consider, primarily the intensity and frequency of the exercise. We need to exercise at a moderate intensity level for about 2.5 hours per week (not all at once!). If you can spare more time, your sleep (and waistline) will benefit. The more time you
workout or the more you increase the intensity of your workout translates into even sounder sleep.

The time of day that you pursue your exercise also affects the quality of sleep that you have. Studies show that ideally you would schedule your cardio activities first thing and your strength training for after work. Both activities help you sleep by reducing stress hormones, but doing cardio too close to bedtime can have
an adverse effect. Interestingly enough, this is believed to be due to our circadian rhythm, which naturally begins to drop our body temperature as we get closer to bedtime. Cardio exercise causes the body temperature to rise more than strength training.

So while it might seem contrary to logic, make sure to make time for your workouts, as they will help you wake up feeling better rested!