To run faster, sleep slower. A growing body of research suggests runners who want to get fast need more slow-wave sleep—the deepest, most restorative stage of slumber. Slow-wave sleep (SWS) is increasingly prized for its ability to help athletes recover from heavy training and hard racing. In fact, many experts say restorative, high-quality SWS is as important to your training as proper nutrition or hydration.

Why is slow-wave sleep important for athletes?

SWS is named for the slow brain waves it creates on electroencephalogram (EEG) tests in sleep labs, which are a sign that the brain has shifted into a repair/prepare mode. During this stage of sleep, memories are consolidated, learning is enhanced, and the brain is cleansed of toxins that may contribute to degenerative brain disease. Also called deep sleep or stage N3 sleep, SWS helps you recover from one day’s workout and prepare for the next.

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Research now shows that even modest deficits in SWS are linked to declines in athletic performance. That’s likely because reductions in SWS are linked to lower levels of human growth hormone (HGH), a compound that affects the body’s ability to repair muscle mass, bones and tendons, says hormone therapy specialist Carissa Alinat, PhD, APRN, founder and CEO of DoctorCarissa.com.

https://www.runnersworld.com/health-injuries/a31020839/runners-slow-wave-sleep/