How much deep sleep do you need

What Are The Stages Of Sleep & What Does Each Stage Do?

• There are five different sleep stages, including REM (rapid eye movement) and NREM (non-rapid eye movement) sleep. The five stages make one sleep cycle, which usually repeats every 90 to 110 minutes.
• Stage 1 non-REM sleep marks the transition from wakefulness to sleep.

  This stage typically lasts less than 10 minutes and is marked by a slowing of your heartbeat, breathing, eye movements, and the relaxation of your muscles.

• Stage 2 non-REM sleep is a period of light sleep before you enter deeper sleep, which lasts roughly 20 minutes.

  Stage two is characterized by further slowing of both the heartbeat and breathing and the brain begins to produce bursts of rapid, rhythmic brain wave activity known as sleep spindles.

• Formerly known as stages 3 and 4, stage 3 (N3) is the final stage of non-REM sleep.

  This is the deepest period of sleep and lasts 20 to 40 minutes. Your heartbeat and breathing slow to their lowest levels, and your muscles are so relaxed that it may be hard to awaken you.

• Stage 5 REM sleep occurs 90 min
  how many sleep cycles should you.have every night
  how many sleep cycles do you have