Sleep Stages

• What are Sleep Stages
  • Light Sleep 
  • Deep Sleep
  • REM Sleep
  • Awakening Stage

What are Sleep Stages

Sleep Stages are the different phases your body cycles through each night. Each has its own job in keeping you rested and healthy. You move through them multiple times a night in cycles, typically going from Light to Deep to REM sleep, before starting the cycle again.

Light Sleep 

Light sleep helps your body start to relax. It's the first stage of sleep in a sleep cycle and makes up about 50% of the total night's sleep. It's key for your brain to process information and essential for memory. It's also when bruxism (teeth grinding) occurs.

Deep Sleep

It makes up about 25% of your total sleep, though as you grow older this percentage decreases. During Deep Sleep, your body repairs and regrows tissue, builds bone and muscle, and strengthens the immune system. It is also when sleepwalking and night terrors can occur.

REM Sleep

It stands for Rapid Eye Movement, and is associated with dreaming. It's not considered restful, but it's essential for memory, emotional processing, mood, and brain function.

Awakening Stage

Includes brief moments of wakefulness during the night, which are totally normal. Your mood is highly affected by which Sleep Stage you wake up in. If you wake up mid-cycle, you may experience sleep inertia. This is the feeling of fogginess immediately upon awakening. Sleep inertia is characterized by a state of impaired cognitive ability that may take up to a couple of hours to dissipate.

The percentages and time durations show how much of your total sleep was spent in each stage.