SWS - Slow Wave Sleep

Slow Wave Sleep is the deepest sleep stage, and the hardest to wake up from (having a large chance to trigger zombie-mode). It is vital, meaning reducing it is unhealthy and it will likely force microsleeps when missing. It has its peak around 21:00-24:00.

SWS is responsible for physical repair of the body, and most people need 90mins to 2h of it, increasing with sickness. It usually appears about 25 minutes into a sleep when no sleep repartitioning or compression has occured and the body assumes every sleep to be a core.

SWS pressure feels like (strong) physical exhaustion/lethargy and is responsible for most non-mental symptoms of sleep deprivation.