How Does the Sleep Cycle Determine Sleep Quality?

How often do you hear that it is important to get seven to eight hours of sleep every night? But it’s not only the quantity of sleep that is important but rather the quality of sleep also plays a role in how rested and refreshed you feel for the next day.

As your body sleeps, you may not be aware of just how much is going on. One of the biggest factors that influence your rest is that while you are sleeping your body goes through different stages of the cycle. These different stages of the sleep cycle have different purposes and various effects on the quality of rest that we get.

An example of this is deep sleep; it is the stage of the cycle that helps you feel refreshed when you wake up in the more.

In order to understand how the sleep cycle affects the quality of rest, let’s take a more in-depth look at the different stages of the sleep cycle.

The stages of the sleep cycle

In order to understand the impact of the cycle on the quality of our rest, we need to better understand the different stages of this particular cycle.

Sleep is firstly divided into two different categories; these are known as REM sleep and non-REM sleep. You first start off in non-REM sleep and then cycle through REM and non-REM sleep. This cycle continues throughout the night about every ninety minutes.

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Non-REM Sleep

Stage 1

The first stage of non-REM sleep lasts for several minutes and occurs as you transition from being awake to falling asleep. In this stage bodily functions such as respiration, heartbeat, and eye movements begin to slow down. Your muscles begin to relax and there is only occasional stirring or twitching. The brain’s activity and the brain’s waves also slowdown in comparison to when you are awake.

This is the lightest stage of rest and it is easy to rouse from. If you wake up often and have a feeling of half-consciousness while sleeping, then this means you are spending more sleep time within this stage of the sleep cycle.

Stage 2

The second stage is also part of the non-REM sleep and it makes about fifty percent of the sleep cycle. This is the stage of sleep that you are most likely to fall into in comparison to another sleep stage throughout the night.

During this stage, the relaxation and slowing of bodily systems continue. The body’s core temperature drops and eye movements stop as well. The brain waves slow down as well, although there are some short bursts of activity. In this stage, you are well asleep but not yet in deep sleep.

Stage 3

Stage three is the final stage of non-REM and during this stage is when you experience deep sleep. This is also known as the restorative phase of sleep, as your body recovers and strengthens itself during this stage.

During this stage of the rest cycle, your breathing and heartbeat are at their slowest and your muscles are relaxed. The brain waves are also the slowest possible during this stage of deep sleep. It is also difficult to wake up during this phase, even if there are stimuli such as loud noises.

The initial stage of deep sleep generally has a duration between forty-five to ninety minutes. This phase has a longer duration during the first half of the night and starts to decrease in length with each cycle over the course of the night.

Deep rest is the stage where you receive the quality of rest that ensures you wake up well-rested in the morning. It is a restorative phase in which the body regenerates, re-energizes and grows.

Stage 4

Stage four is the first REM sleep stage, it occurs roughly ninety minutes after passing through the non-REM sleep stages. During this stage, your eyes move rapidly from side to side, which is one of the distinguishing factors of REM sleep.

In addition to this people also experience dreams as the brain’s activity increases to almost a wakeful state. The heart rate increases to near its wakeful state and the rate of breathing becomes faster which can even be irregular at certain moments. Finally, the body’s extremities might even become paralyzed.

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Deep sleep and sleep quality

High quality of rest is associated with deep sleep as this stage of the cycle has many benefits.

During this phase the metabolism of glucose within the brain increases, which promotes the development of short term and long-term memory as well as overall learning capabilities.

During deep rest, the pituitary gland also secretes important hormones which include hormones that are vital for human growth and development of the body. Some other benefits of deep rest are that it provides the restoration of energy, the regeneration of cells and the increase of blood which is supplied to the muscles.

In addition to this deep rest also enhances and promotes the growth and repair of tissues, bones, and muscles. It strengthens the immune system, to make the body stronger and ready to combat infections and other foreign bodies.

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What happens if you do not get enough deep sleep or good quality sleep?

It is very important to get enough sleep and to get good quality sleep. Deep rest is part of the overall cycle, which is responsible for processing, storing, and converting information. It helps process the information that you encounter on a daily basis.

If you do not get enough deep rest, the brain cannot convert this information into your memory. Not getting quality rest can lead to many conditions such as heart diseases, strokes, Alzheimer’s, and diabetes.

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Not only is the quantity of rest you get each night an important factor of waking up refreshed but the quality of rest you get is also important. The stage of the cycle that is most connected to quality rest is a deep sleep. It is important to get enough deep rest in order to ensure your body is well-rested and to prevent diseases such as Alzheimer’s and diabetes.