An exercise routine can actually improve sleep quality, according to Alon Avidan, professor of neurology and director of the UCLA Sleep Disorders Center. However, there are a few caveats: How you exercise matters and what time you work out can have a big impact, too. 

“Regular workouts that are consistent, three to four times a week, [at least] 30 minutes in duration are much better for you than working out once a week for two hours,” Avidan told HuffPost.

The consistent part is critical. A 2013 study found that people with insomnia only started to sleep more soundly after four months of regular, weekly workouts, the New York Times reported. (Apologies to those weekend warriors who pack in a few hours of intense activity only once a week. You’ll hit the recommended amount of exercise, but you won’t reap the benefits of better rest.) 

Avidan also recommends endurance-based, aerobic workouts to promote better sleep. Running, swimming, bicycling and brisk walks all help.

Additionally, it’s important to exercise either early in the morning or in the afternoon. High-intensity exercise right before bed can be disruptive to sleep, according to Helen Driver, manager of the sleep disorders lab at Kingston General Hospital and Queen’s University in Ontario, Canada. If you want to work out before you settle into your sheets, try something less strenuous.

“Exercise, if it’s built into your routine, can help you sleep,” Driver told HuffPost. “Stretching exercises, to running on a regular basis, to strength exercises. Yoga can improve people’s sleep quality.” 

The reason exercise may help with sleep lies in body temperature. The workout causes your body heat to dramatically rise and then it slowly cools down for several hours after the activity ends. This steady drop in core body temperature signals the brain that it’s time to go to bed, Avidan said. A warm bath or shower at night can also spark the same process.

Just make sure that when you finally hit the hay that you’re also setting yourself up for a good night’s rest in general. Avidan also stresses that it’s important to ditch your devices before bed, otherwise you may undo all of the work you did.

“Artificial light makes it very difficult to fall asleep because it keeps the circadian clock very active,” he explained.

So work out consistently, unplug and then drift off. You just might wake up feeling pretty refreshed.