FAQ: What are Sleep Cycles and Sleep Stages?

We sleep in cycles of 90 to 120 minutes throughout the night. in that time, we cycled through the different stages of sleep.  There are four to five sleep stages – non-REM and REM sleep.

Sleep is divided into REM sleep (Rapid Eye Movement sleep) and non-REM sleep.   The first 3/4 stages of sleep, are non-REM Sleep, and the fifth is REM Sleep and is when we dream.

We cycle through the different stages of sleep, roughly five times a night – sleep cycles.

Each sleep cycle lasts 90 – 120 minutes and each sleep stage in each sleep cycle usually lasts between 5 to 15 minutes.

For more information, see my blog on Sleep Cycles and Sleep Stages