Polyphasic Sleep and Exercise

Whether you’re a pro athlete or you’re trying a new workout plan for the first time, sleep can make or break your success—so much so that entire lines of mattresses exist just for the purpose of improving athletes’ sleep (check out our full list of the best mattresses for athletes). Better sleep reduces your risk of injury, reduces your recovery time, and increases your performance for future exercises.

That said, better sleep doesn’t just mean more sleep. In fact, some athletes deviate from the standard eight-hour night and practice polyphasic sleep, using daily naps or segmented rests to optimize their recovery and muscle development.

Ultimately, the polyphasic sleep schedule that works best for you depends on two factors: your athletic goals and what feels best for your body. So, let’s take a closer look at how sleep and exercise connect.

What Happens During Recovery?

Pushing your limits in activities like running or lifting can be great for your health, but that doesn’t mean it’s easy on your body. During nearly every kind of sport, your body accumulates damage, tears, and stress to its muscle fibers and bones. The body also undergoes inflammation in response to this strain, and the body raises its levels of cortisol—the “fight or flight” or stress hormone. Finally, once the exercise is completed, your body can begin the recovery process.

Recovery is the period of rest and growth following exercise, and it becomes more important with higher levels of physical strain. Once a workout is completed, the body begins responding to the stress of the exercise, replenishing muscle glycogen (the muscles’ fuel), and repairing damaged or inflamed muscle tissues. Along with diet, sleep is essentially to ensure this repair process can properly take place.

Sleep and Recovery

Deep sleep stages, like REM (Rapid Eye Movement) and SWS (Slow Wave Sleep) are where most of your sleeping recovery happens.  While an athlete sleeps, their muscles, brain, and heart slow down allowing for a level of rest that can’t be achieved while awake. Ultimately, this deep sleep recovery allows muscles to return to and exceed prior levels of performance.

Within REM sleep specifically, your muscles (including the heart) release their tension causing a drop in blood pressure and in breathing rate. During this period of deep rest, your body also secretes more oxygen and nutrients like glycogen into your bloodstream. Next, in the SWS stage of sleep, your body focuses on repair by secreting HGH (Human Growth Hormone). This hormone plays a key role in how the body’s muscles rebound and become stronger from damage. 

Additionally, during a night of restorative sleep, the body also lowers its cortisol levels, boosts the immune system, and restores cognitive and cardiovascular functions. Finally, along with cortisol, quality sleep reduces the hormone ghrelin which is responsible for excessive hunger and cravings.

However, while all athletes benefit from quality sleep, it’s not always in the same way.

How Much Rest Is Needed For Recovery?

If you’re active and want to try polyphasic sleeping (naps or segmented sleep), the right sleep schedule and sleep hours for you will largely depend on whether you’re primarily an endurance (distance running, cycling, etc.) or a strength athlete (powerlifting, bodybuilding, etc.). More specifically, your sleep and exercise plan are determined by what kind of muscles you use, how long you use them, plus your body composition.

Strength Athletes

For strength athletes like bodybuilders and powerlifters, the goal is bulking and building muscle mass. However, this doesn’t just mean eating more and spending more time in the gym—it also means more time in bed.

To maximize workout gains, strength athletes can sleep for up to 10 hours a day, but that doesn’t have to be one continuous rest. In fact, many athletes polyphasically segment their sleep, meaning they wake up in the middle of the night—on purpose.

This may sound counterintuitive to getting a good night’s sleep, but these strength athletes use their brief waking time to eat food high in protein. When they return back to sleep, their bodies hit the SWS stage of sleep, responsible for muscle growth and repair, with an extra boost of protein. Even during the day, strength athletes can use this same strategy, following up a high protein snack with a deep nap.

Endurance Athletes

Running a marathon might be one of the most tiring things you can do, but endurance athletes actually don’t require as much sleep as you might believe. In reality, average ultramarathoners report training on just seven to nine hours of sleep each night. 

But, while endurance athletes have different sleep needs than strength athletes, they still also benefit from polyphasic naps. Instead of building extra muscle during these naps however, like lifters, runners will get an energy boost and a decrease in hunger.

Naps aside, the reason behind this surprising lack of sleepiness from distance runners is how they recover. While recovery for a strength athlete means building muscle mass and strengthening large muscle groups, endurance recovery focuses more on the heart. And, since many endurance sports are at a lower intensity but longer duration than strength sports, runners’ recovery is more about repairing than bulking.

Sources

Doherty, R., et al. (2021). The Sleep and Recovery Practices of Athletes. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072992/

Cleveland Clinic (2022). Glycogen: What It Is & Function. https://my.clevelandclinic.org/health/articles/23509-glycogen

Cleveland Clinic (2022). HGH (Human Growth Hormone). https://my.clevelandclinic.org/health/articles/23309-human-growth-hormone-hgh

Martin, T. (2018) Sleep Habits and Strategies of Ultramarathon Runners. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5942705/

Robson, D. (2021). The Importance of Sleep. https://www.bodybuilding.com/content/the-importance-of-sleep

Society for Endocrinology (2022). Ghrelin. https://www.yourhormones.info/hormones/ghrelin/

Swartzendruber, K. (2013). The Importance of Rest and Recovery for Athletes. https://www.canr.msu.edu/news/the_importance_of_rest_and_recovery_for_athletes