Exercising before sleep may not be a bad thing

ATLANTA (FOX 5 Atlanta) - Between work, family commitments and the daily grind, it's hard to work in a workout.

Emory internist Dr. Sharon Bergquist says many of us already feel overloaded.

"I think with so many people just leaving extraordinarily busy lives," Bergquist says. "There just aren't enough hours in the morning to get exercise as well as all of the other responsibilities. So, sometimes, night time is the only time that's left."

For years, we've been told not to exercise too close to our bedtime, because it will rev us up and make it harder to sleep.

But a new study by Swiss researchers upends the idea exercise before bedtime is bad.

"It's saying well, not really," Bergquist says. "We're not seeing that it's disrupting sleep. So, if the only time of day you can exercise is evenings, you should go ahead and just do that."

Researchers from the Institute of Human Movement Sciences and Sport at ETH Zurich examined 23 previously-published studies on sleep and exercise.

The study focused on healthy volunteers with no sleep issues.

Researchers found those who worked out within 4 hours of bedtime got slightly more deep, restorative sleep than volunteers who didn't exercise before bed. 

So, instead of being bad, evening workouts may slightly improve sleep.

Researchers recommend avoiding high-intensity exercise close to bedtime because it can raise our heart rate.

That can make it more difficult to sleep when it's time to go to bed.

Bergquist says, if you have a choice, she still recommends a morning or afternoon workout.

"We know from studies that look at what happens when you exercise in the daytime, that people do get better sleep," she says. "They fall asleep faster and they spend more time sleeping when they're in bed. So, if you could do daytime exercise over evening exercise, that is still the preferred way to do it.  But if the only time you have is evenings, then you should still go ahead and exercise."