The importance of the sleep stages

Our sleep is made up of several sleep cycles in which we go through different sleep phases night after night. Find out here which sleep phases there are and the importance of the individual sleep stages for a restful night.

Table of Contents

1. How does our sleep work?
2. The sleep phases at a glance
3. The importance of sleep cycles
4. Conclusion

1. How does our sleep work?

Our sleep is essential for our energy balance and numerous important recovery, repair and construction processes in our brain, tissue and cells. Sufficient and restful sleep is therefore one of the most important foundations for a healthy functioning of the body and an efficient, healthy everyday life. Experts generally recommend that adults sleep 7 - 8 hours a night - and it's no coincidence. Every night our sleep is made up of different sleep cycles, which in turn consist of different sleep stages: the falling asleep phase, light sleep phase, two deep sleep phases and REM sleep. To feel relaxed in the morning, it is very important to go through a sufficient number of sleep cycles and give the body time to regenerate. We give you an overview of the different stages of sleep and explain the importance of the individual phases for restful sleep.

2. The sleep phases at a glance

Sleep phase

The falling asleep phase refers to the last minutes before "real" sleep. In this phase, the body switches off, relaxes and comes to rest. In adults, the sleep phase lasts about 5-20 minutes.

Light sleep phase

During this period of sleep, our muscles relax, pulse and breathing become more even, and body temperature drops. We spend almost half of our sleep time in this rather superficial sleep, in which we are still quite susceptible to external stimuli such as noise or light. On average, we reach the light sleep phase about 15 minutes after falling asleep.

deep sleep phase

The light sleep stage is then followed by deep sleep. It dominates the first third of the night and ensures that our body shuts down even further, heartbeat and breathing slow down and blood pressure drops. In this stage, the so-called "Slow Wave Sleep", the frequency of the brain waves drops and nerve activity is significantly reduced. Now the energy stores in our brain are recharged and numerous hormones and messenger substances are released that control essential metabolic and regeneration processes. Deep sleep is therefore the central recovery period of our body, in which proteins, cells and tissue are repaired, detoxified and built up, the immune system is trained and energy reserves are renewed. And our brain is also active, since the declarative memory, which is responsible for learning facts and memories, is formed during deep sleep.

REM sleep phase

Following deep sleep, we slide into the dream sleep phases, also known as REM phases. REM stands for "Rapid Eye Movement", because during these sleep periods our brain processes and evaluates the experiences of the day and we move our eyes quickly back and forth under the closed eyelids. For this to work, blood flow to the brain increases, blood pressure rises, and our heart rate and breathing also become more irregular. At the same time, we are in what is known as sleep paralysis, in which the brainstem blocks the transmission of commands to our muscles to protect us from uncontrolled movement and injury during vivid dreaming. Important processing and learning processes take place in the brain during REM sleep and the procedural memory, which forms the basis for subconscious abilities such as automated movement sequences and motor learning, is formed.

3. The importance of sleep cycles

During the night we go through several sleep cycles. A cycle lasts approx. 90 to 110 minutes and consists of the fixed sequence of the five sleep stages, with the relationship between the sleep phases within a sleep cycle changing over the course of the night. At the beginning of our sleep we experience longer deep sleep phases, because these are urgently needed to restore the energy reserves used up during the day. At the end of the night we then spend more time in REM sleep, in which the available energy can be used for important brain functions. The first two sleep cycles, the so-called core sleep, are therefore particularly important for the recovery of body and brain and the most important constructive processes take place in our cells and the nervous system. For an all-round relaxing awakening in the morning, however, it is important to go through about 4 to 7 sleep cycles and thus sleep between 7 and 8 hours.

Learn more?

In our new podcast sleep SMART! we talk to Dr. Markus Dworak about the sleep phases and learn more interesting and scientific information from him about how important our sleep cycles and the different sleep stages are for a restful night and a healthy day! Listen now ➨

4. Conclusion

• Sleep consists of several sleep cycles that differ over the course of the night and are divided into five sleep stages

• The five sleep stages are: falling asleep phase, light sleep phase, deep sleep phase, REM sleep phase

• In deep sleep, energy reserves are filled and the most important regeneration and build-up processes take place

• Refreshing sleep consists of 4 - 7 sleep cycles and therefore lasts between 7 and 8 hours per night at best.

Greetings and see you soon!