Introduction to REM Sleep and Sleep Cycles

That thing we dreaded as kids but can’t seem to get enough of as adults: sleep. No matter our age and whether we want it or not, sleep is an integral part of every aspect of our health, whether it be mental, physical or emotional. While you sleep, your body works to reorganize and repair cells, restore energy, store new information and even rids itself of toxic waste. 

Every night, or whenever you sleep, your sleep has an important structure with different sleep stages. Each stage serves a unique purpose. In a typical, healthy adult, there are four stages of sleep. Knowing each one will also help you understand the magic of sleep and why it is such an essential part of life. We’re here to help!

Stages Of The Sleep Cycle

The four stages of sleep are composed of both non-REM and REM processes. REM stands for Rapid Eye Movement sleep, while non-REM accounts for sleep stages that do not involve REM. It is important to note that each stage can occur more than one time during a sleep cycle. 

  • Non REM stage 1 lasts for five to 10 minutes
  • Non REM stage 2 lasts for 30 to 60 minutes
  • Non REM stage 3 lasts for 20 to 40 minutes
  • REM sleep lasts from 10 minutes to 60 minutes
Woman asleep with cat
Pets also have a REM sleep stage

REM Sleep Cycle

What is REM sleep? REM is the stage of sleep we are typically most familiar with. It’s associated with numerous physiological changes, including faster heartbeat and breathing, increased brain activity, eye movement and muscle relaxation. 

REM occurs around 90 minutes after we fall asleep and happens more than once during a full sleep cycle. The first period of REM sleep typically lasts about 10 minutes and the time will increase with each occurrence until reaching 60 minutes on the last cycle of the night.

Have you ever noticed someone twitching while they are sound asleep? Whether it was your significant other or your dog, they were most likely experiencing REM sleep at that moment unless they had just fallen asleep. This stage of sleep is associated with intense dreaming and a mixture of brain excitement and muscular paralysis. 

Babies are in REM stage for about half of their sleep cycle, but we get shorter periods of REM sleep as we age.

Non-REM Sleep Cycle

Non REM sleep serves an important purpose in sustaining life. Our body relaxes and works to repair and regenerate cells, tissues, bones, and muscles during these stages. Just like it happens with the REM stage, adults have shorter periods of deep sleep and spend most of the night in the first two stages of non-REM sleep. 

Stage 1

Non REM stage 1 is the time between when you shut your eyes and begin to fall asleep. If woken during this period, you may feel like you were never asleep. During this stage, respirations start to decrease, muscles relax and eye movements slow down. 

Stage 2

During non-REM stage 2, your body’s activities slow even further. Body temperature drops, brain activity slows and eye movements stop. We spend about half of our time asleep at this stage.

Stage 3

Non REM stage 3 might be mistaken for REM sleep. This is a period of deep sleep that results in waking up feeling energized and refreshed the next morning. It is during this time that your respirations slow to their lowest levels. Brain activity slows so much that the sleep during this time is called slow-wave sleep.

Little girl sleeping
Don’t confuse REM and Deep Sleep

Deep Sleep vs. REM

The most important thing to remember about deep sleep stages and REM is that they all serve an essential purpose. Deep sleep stages focus on body restoration and reparation, while REM focuses on brain restoration and reparation. 

If you are experiencing physical or mental issues, check into your sleep patterns and identify what you might be lacking.

Deep sleep purpose:

  • Cell replacement
  • Wound healing
  • Muscle tissue building
  • Overall physical health

REM purpose:

  • Brain restoration
  • Learning improvement
  • Long-term memory improvement

What Causes Changes To Sleep Stages

If you are not getting adequate sleep, there are many negative consequences that may include loss of focus, lowered sex drive, weakened immunity, depression, obesity, heart disease, anxiety and more. 

What might cause disruptions to your sleep cycle?

Man sleeping with pillow
Keep a sleep log

How To Improve REM and Non REM Sleep

Understanding the importance of proper sleep is the first step. Now that you know that, you may be wondering how you can fix your sleep issues and improve your overall quality of life. 

Start by keeping a sleep log. This will help you identify triggers and other disruptions to your sleep. Then, focus on improving your sleep hygiene. Sleep hygiene includes habits that enhance your ability to fall asleep and remain asleep for an adequate amount of time. Here are some solid tips to get you started:

  1. Keep a consistent eating schedule
  2. Avoid alcohol at night
  3. Exercise in the mornings
  4. Avoid caffeine products or other stimulants like nicotine
  5. Avoid drug use 
  6. Avoid daytime napping 
  7. Turn off electronics one hour before bedtime
  8. Stretch or do yoga in the evening 
  9. Keep your bedroom nice and cool 
  10. Try some melatonin, CBD oil or diffuse essential oils

For more expert tips on improving REM and non-REM sleep, check out 101 Tips for Better Sleep.