SLEEP CYCLE

Each night you pass through 2 states of sleep: NREM (non-rapid eye movement) and REM (rapid eye movement) sleep. On average it takes about 90-110 minutes to cycle through both NREM and REM sleep. The complete cycle repeats between 4-6 times a night.

Non-rapid Eye Movement (NREM) Sleep

• Stage 1:
  During this stage, you drift between being awake and falling asleep; brain waves and muscle activity starts to slow; you may feel like you’re falling followed by sudden jerky movements.
• Stage 2:
  During this stage, you enter a period of light sleep; brain waves and heart rate slow down and temperature decreases.
• Stage 3:
  During this stage, you enter a deep sleep and it is harder to be woken up; this is the most restorative stage as your muscles relax, blood supply to muscles increase and your body grows and repairs tissue while your energy is renewed.

Rapid Eye Movement (REM) Sleep

• This state of sleep provides energy to the brain and body and supports daytime performance. In this state your brainwaves are fast, your brain becomes more active and you dream.
• Rapid eye movement sleep stimulates the brain regions used in learning and is critical towards memory consolidation and cognitive functioning the next day.

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