What is deep sleep?
Deep sleep, or N3 slow-wave sleep, is the most physically restorative stage. It is when growth hormone is released, the immune system replenishes, and the brain clears metabolic waste through the glymphatic system.
The physical restoration
Growth hormone, tissue repair, immune memory consolidation, and physical recovery all peak during N3. Athletes notice the loss of N3 most quickly.
Brain cleaning
The glymphatic system flushes amyloid-beta and other waste during N3. Reduced deep sleep over years contributes to neurodegenerative risk.
Maximizing N3
Adequate total sleep, cool room, no alcohol, regular exercise (not at night), and consistent schedule all support N3. It cannot be 'caught up' with naps.
Sources
- Matthew Walker, Why We Sleep (Scribner, 2017). Why We Sleep: Unlocking the Power of Sleep and Dreams
Tired of hitting snooze?
ByeBed replaces the snooze button with a mission. Math, push-ups, photo. The alarm only stops when you complete it. Free to try.
Download ByeBed on the App Store