What is a Sleep Cycle?

What is a Sleep Cycle

What is a Sleep Cycle? : How Much Sleep Do We Need?

This will vary from person to person. Most healthy adults need between 7½ – 9 hours of sleep a night so that we can function at our best.

Children and teenagers need more. Between 12 – 18 hours. The quantity of sleep that teenagers and pre-teens actually get has decreased because of the impact of technology.

What is a Sleep Cycle?

A sleep cycle lasts approximately 90 – 110 minutes.

Each stage may last between 5 to 15 minutes.
During your night’s sleep, your body will move through 4 different stages of sleep:

  • NREM (Non-Rapid Eye Movement) sleep.
  • REM (Rapid Eye Movement) sleep.

The first 3 stages make up our NREM sleep.

The 4th stage is when REM occurs.

Once you have finished REM, you will then return for another cycle of sleep and repeat the 4 stages.

Most of us need 4 – 5 Sleep Cycles in a 24 hour period.

What is a Sleep Cycle? : The 4 Stages 

The Sleep Cycle is divided into the following stages, with each becoming progressively deeper.

  • Stage 1 – NREM 1 (Light phase of sleep)
  • Stage 2 – NREM 2 (Light phase of sleep)
  • Stage 3 – NREM 3 (Deeper phase of sleep)
  • Stage 4 – REM        (Intense dream and brain activity)
What is a Sleep Cycle?

What is a Sleep Cycle? The 4 Stages of Sleep Explained

What is a Sleep Cycle? : The 4 Stages Explained

Stage 1 – NREM 1 (light phase of sleep)

  • This is the stage when you are first falling asleep. You are on the border between being awake and being asleep.
  • You will feel like you’re floating in and out of consciousness. We are partially awake while your mind begins to drift.
  • This may cause your muscles to jerk suddenly. A falling sensation may follow.
  • Your eyes are closed during this stage and they will move slowly.
  • It’s easy for you to wake you up during this stage.
  • This stage is also known as the transitional phase.
  • This phase may last for 5 to 10 minutes.
  • It is called ‘hypnic myoclonia’.
  • After winding down in stage 1 you will slip into stage 2.

Stage 2 – NREM 2 (light phase of sleep)

  • This is when you will start to fall asleep and disconnect with the outside world.
  • Almost 50% of the time spent asleep is in Stage 2.
  • Breathing and heart rhythm will take on regular patterns.
  • Heart rate will slow down.
  • Your body temperature will drop. Your body is getting ready to enter deep sleep.
  • During Stage 2 your eye movement stops.
  • Your brain waves will slow down. Except occasionally it will produce sudden increase in brain wave frequency known as sleep spindles.

Stage 3 – NREM 3 (deeper phase of sleep)    

  • This is the deep stage of sleep.
  • You will find it hardest to wake during Stage 3.
  • If you try and wake someone during this stage, they will most likely be disoriented and groggy for a few minutes.
  • Slow wave sleep is a NREM phase of sleep.
  • It is the deepest sleep that your body enters throughout the night.
  • Your blood pressure will drop even further.
  • Your breathing will become deeper and slower, and more rhythmic.
  • During slow wave sleep there is no eye movement, and the body becomes immobile. However, even though there is no muscle movement, the muscles still have the ability to function.
  • Sleep walking, and nightmares are experienced during these stages.
  • Bedwetting for children may occur during these stages.
  • During Stage 3, body will repair, regrow tissue, build bones and muscle tissue. Also, your immune system will strengthen.
  • Your hormones will also help to control your appetite and help limit feelings of excessive hunger the following day.
  • As you get older, you sleep more lightly and get less deep sleep.
  • Ageing is also linked to shorter time spans of sleep, although studies show you still need as much sleep as when you were younger.

Stage 4 – REM (intense dream and brain activity)

  • Stage 4 (Rem) of sleep kicks in around 90 minutes after falling asleep.
  • The first time you go into REM sleep, it will last around 10mines. For each additional cycle, you will see an increase in REM sleep.
  • Most dreaming takes place in Stage 4 as a result of heightened, desynchronized brain waves.
  • This stage of sleep revitalizes the brain, supporting sharp and alert daytime function.
  • Stage 4 is the only stage of rapid eye movement (REM).
  • Most adults spend about 20% of sleep in REM, while infants spend almost 50%.
  • During non-REM sleep, the mind rests while the body heals, but in REM sleep the mind energizes itself while the body is immobile.
  • During this stage of REM sleep the eyes dart in various directions while the limbs and muscles are temporarily paralyzed.
  • Your breathing will become faster.
  • You heart rate and blood pressure will rise from the levels they were in previous stages.
  • During REM sleep, your body loses the ability to regulate its temperature. Therefore, if your body is hot or cold you may wake during this REM stage.
  • REM sleep is very important for learning. It stimulates areas of the brain used in learning.
  • Individuals begin waking up at the end of stage 4.

‘Sleep is that golden chain that ties health and our bodies together’

(Thomas Dekker)


What is a Sleep Cycle? : Other Things to Consider
  • WELL BALANCED DIET – Make sleeping easier by ensuring you follow a healthy well-balanced diet.
  • FRESH AIR AND EXERCISE – Getting fresh air and exercise will help with sleep.
  • NATURAL BEDDING – Natural bedding will help keep your body at the optimum temperature. Helping you to sleep through the night and completing fully the 4 stages of sleep.


What is a Sleep Cycle

Natural Bedding will help to regulate your body temperature

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