Sleep cycles

Understanding Your Sleep Cycles

Each night a person goes through 4 to 6 cycles of sleep which last about 90 minutes each.

There are two type of sleep, rapid eye movement or REM sleep, and non-REM sleep. Dreaming can occur in either of these types of sleep. Non-REM sleep has 3 stages. 

Non-REM Sleep

Stage 1

This the dozing off stage which lasts no more than 10 minutes. The eyes are closed but its easy to be woken up during this stage.

Stage 2

This when you fall into a light sleep. Heart rate and body temperature drop slightly. Stage 2 can last from 10 minutes up to an hour.

Stage 3

This the point of deepest sleep. The muscles relax, blood pressure and the rate of breathing fall. The brain produces delta waves. This phase lasts 20 to 40 minutes. Stage 3 is the most crucial stage for restorative sleep. It is the time when the body recovers and in children when the body grows. This deep sleep also enhances creative thinking and inspirational or insightful thought. It’s hard to be aroused from this sleep state. 


REM Sleep

As the night progresses, the deep sleep stages get shorter and shorter and more time gets spent in REM sleep. 

During REM sleep, brain activity starts rising again, almost to the levels of when you are awake. However, your muscles are almost in a paralysis, the body doesn’t move or twitch during this time except for the muscles of breathing and the muscles of the eyes. Even though the eyelids are closed, underneath them the eyes dart about quickly. REM sleep is essential for memory, learning and creativity. This is the time of sleep where the most vivid and intense dreams are experienced, the ones you remember when you wake up.  In the first sleep cycle of the night, REM is at its shortest, lasting only about 10 minutes but this gets longer through the subsequent sleep cycles of the night. REM should make up about a quarter of the sleep an adult has each night. In new born babies its 50%!

Over the course of the 4 to 6 cycles of sleep that occur a night, you go from Stage 1 of non-REM, moving into stage 2, then stage 3, then back to 2 and 1 and in that light phase of Stage 1 is where you slip into REM sleep. When the REM phase is over you cycle back through the non-REM stages again. As you approach the early hours of the morning, generally you spend less time in deep sleep, and increasing time in the more active sleep state of REM. 

There’s a wealth of evidence that poor sleep or lack of sleep over time can cause significant health problems. If you’re serious about getting healthier, slimmer, more fertile, reducing pain and stress, having better brain power and even living longer, then frequent late nights and too little sleep need to go. With a greater understanding of just how important sleep is, it’s so important to decide to make sleep a priority. Here are some easy, actionable tips to help you improve your sleep.

Share this post