Sleep Stages: What Do You Need To Know About Them?

July 23, 2020

Sleep Stages: What Do You Need To Know About Them?

We all know that we should be getting between 7 - 9 hours of sleep each night, ideally. However, this isn’t always possible whether due to having young children or going through a period of stress. 

Do you feel that your sleep quality has been less than great lately? Are you looking for ways to improve how you sleep? First, you need to understand what happens to your body during each of the sleep stages. Knowing exactly what happens in your body, most specifically your brain, can make the difference when improving sleep quality. 


Looking To Improve Your Sleep Cycle?

People have been looking to improve their sleep cycle for years. You have more than likely come across numerous articles on the Internet and in magazines titled “How to achieve your best night of sleep yet”. But why is improving it so important? 

Well, the answer is because of the quality of sleep that we receive regularly can impact other necessary bodily functions that we rely on. 

For example, have you ever noticed that you are a lot more forgetful when you’ve missed a few hours of sleep? Tiredness and chronic fatigue affect our cognitive abilities and can decrease both memory retention and concentration levels. Additionally, disrupted sleep cycles can impact stress levels and cause emotional distress.

If you are looking to improve your sleep cycle, then it is important to understand the biological roles that each sleep stage plays in helping us to feel rejuvenated and rested every morning. 


What Are Sleep Stages And Why Are They Important? 

During sleep, people pass through a series of physiological stages, i.e. sleep stages. Each sleep stage has its purpose and ensures that your body is given the ability to repair and restore itself to continue working optimally daily. 

As you may already be aware, your body possesses an internal body clock, also known as a circadian rhythm, which regulates your sleep pattern and dictates when you should fall asleep. This internal process along with other brain structures and chemicals produces the stages of sleeping and waking. And each stage is necessary for good quality sleep. 

During the night, a person can expect to pass through stages of sleep that alternate between quiet sleep and what is known as REM sleep. Quieter sleep stages are needed to restore the body, while REM sleep is needed to restore the mind. 


Understanding The Stages of Sleep: A Guide

Next, you need to understand what happens in your body during each of the five core sleep stages. Below, we talk you through the physiological events that happen in the brain and body during each stage so that you can begin your journey to getting the quality rest you deserve. 


Stage One: Sleep Onset

The first stage of sleep is often considered as the transitional stage. It begins when you first put your head on the pillow and takes course over the length of time that you begin to drift in and out of consciousness. It is brief, light and a non-REM related phase. 

During sleep onset, you will still be awake but will notice your mind starting to drift off and wind down. If you’ve ever experienced the falling sensation when going to sleep, this means that you are in stage one. It is also not uncommon for your muscles to twitch or jerk you back awake during this sleep stage. Once your mind and muscles begin to fully relax, you will begin to transition into stage two.


Stage Two: Slow-Wave Sleep 

The second sleep stage is referred to as slow-wave sleep and is a quiet sleep phase. Unlike sleep onset, many people can spend a long time in the second stage. During slow-wave sleep, your body will alternate between periods of muscle relaxation and tension. It is also during this phase that other physiological changes happen such as a drop in heart rate, a decrease in body temperature and a decrease in brain wave activity. 

It is important to note that brain waves will experience occasional bursts during slow-wave sleep can sleep spindles. These play an essential role in sensory processing and long-term memory consolidation.  


Stage Three: Entering Deep Sleep

Stage three marks the beginning of deep sleep and the transition into the REM phases of sleep. When your body is preparing for deep sleep, it experiences further decreases in both breathing levels and heart rate. At this point, your muscles are fully relaxed making it hard for others to wake you at this point. Additionally, it is during this stage that your brain records the lowest levels of brain wave activity. 


Stage Four: Deepest Sleep

This is the period of deep sleep that you need to feel the most refreshed the next morning. It tends to occur for longer periods during the first half of the night and can be harder to drift back into as morning approaches. 

During our deepest stage of sleep, our bodies carry out the necessary repairs needed to help us recover from our daily activities. This happens once our breathing, temperature and heart rate has slowed down to an adequate level. Deepest sleep allows the body to release important hormones needed to restore cellular energy and carry out tissue repair. 


Stage Five: REM Sleep 

Lastly, the final stage of sleep is rapid eye movement (REM) sleep. During REM sleep, a person’s eyes will move around rapidly in various directions. Breathing levels are shallow and irregular while heart rate and blood pressure levels most commonly begin to rise. 

During this phase of sleep is when we experience vivid dreams. To keep us protected, our bodies will temporarily become paralyzed to prevent us from getting out of bed and acting out our dreams. It is this sleep stage that helps to revitalize our brain the most. REM sleep allows our brains to restore itself resulting in the brain being more sharp and alert once the morning comes. 


Sleep Apnea: How Does It Impact The Sleep Cycle?

As a sleep disorder, Obstructive Sleep Apnea (OSA) can dramatically impact the sleep cycle. Most notably, the REM stages of sleep. As this condition is characterized by causing frequent sleep disruptions during the night it can easily throw a patient’s sleep patterns off track, especially if they aren’t using adequate treatment options like CPAP therapy. 

Sleep studies have found that although apneic events can happen during any sleep stage, they are most likely to happen during the REM stages of sleep. 

The more apneic events that happen during each hour of sleep, the less chance you have of reaping the benefits of deep sleep. As we learnt above, REM sleep is needed to revitalize the brain. This won’t be achieved if sleep is fragmented. That is why so many OSA patients note experiencing chronic fatigue and cognitive functioning difficulties.

Without the body and brain being given the chance to fully restore and repair itself each night, many OSA patients that leave their condition untreated will continue to have poor sleep cycles.  


Ways To Get Your Sleep Quality Back On Track

Not reaching each of the sleep stages puts you at an increased risk of suffering from sleep deprivation on an ongoing basis. If you are looking to prevent this, then you need to take action and get your sleep quality back on track. 

Both natural and medical routes can be taken when improving sleep quality. In the case that you believe you may be suffering from OSA, you must go and speak with a physician and sleep specialist. They will be able to diagnose your symptoms and prescribe you with a treatment plan. 

However, there are simple changes you can make to your daily routine that will help you improve your sleep quality in the long run.

  • Try to be consistent with your sleep and waking times to get your body into a natural sleep pattern
  • Reduce blue light exposure in the evening time. That means limiting your device usage, wearing blue filter glasses and turning off the TV two hours before going to sleep
  • Stop consuming caffeine six hours before going to bed
  • Take sleep-friendly supplements such as melatonin which will help to prepare your body for sleep 
  • Optimize your bedroom environment by trying to eliminate external noise, light and any artificial light. All sleep environments should be quiet, calm and relaxing to promote good sleep quality. 

Improving sleep quality is not an impossible task once you understand the importance of each of the sleep stages. Reaching each of these sleep phases is vital to make sure that we achieve great sleep quality. So, whether your poor sleep cycle is a result of OSA or too much exposure to digital devices, there are steps you can take to get your sleep quality back on track. 

Looking to improve your sleep with CPAP therapy? Our experts at can help answer any questions you may have regarding Obstructive Sleep Apnea and CPAP supplies. Get in touch with us today.

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