Sleep is one of the vital functions we enjoy the most but know the least about. The phases of sleep determine to a large extent the quality of our rest and our energy for the next day.
Our brain needs to sleep to recover energy and process the information it receives from day to day. In addition, in each of the phases of sleep, our brain performs different processes. There are 5 different stages of sleep, of which 4 are slow sleep and one is fast sleep (REM).
The phases of sleep alternate in a cyclical manner throughout the time we sleep; so that every 90 minutes or so we begin a new phase.
During the first 4 phases, our body begins to rest little by little. Our breathing and heart rate decrease slightly. During the last phase, REM sleep, is when our body recovers and replenishes its energy. Our muscles relax, physical recovery takes place and our memory settles down. This last phase is the one that determines the quality of our rest.
Phase 1: numbness
It is the first of the sleep phases. Our body enters a state of drowsiness that lasts approximately 10 to 15 minutes. The brain activity is very similar to the one we have when we are awake, so it is easy to wake up with not very loud noises.
Phase 2: light sleep
In this second stage of sleep, both heart rate and respiratory rate decrease. In addition, our body is gradually disconnected from everything that surrounds it and it is more difficult for us to wake up. This is because the nervous system blocks the pathways for sensory information. This phase of sleep begins to be restorative and occupies about half of our total sleep time.
Phase 3: transitional phase to deep sleep
In this phase, our sleep begins to deepen and our sensory block intensifies. It is a very brief phase in which we spend about 2 or 3 minutes. It is very difficult for us to wake up in this phase, but if we do, we will have a very intense feeling of confusion and feel out of place.
Phase 4: Delta sleep
In this phase we are deeply asleep and it is also quite difficult to wake up. This phase determines the quality of our physical and mental rest. Images are beginning to appear here, but we are not yet dreaming. It usually lasts about 20 minutes.
The star of the sleep phases: the REM phase
This is the last of the sleep phases. Its acronym refers to the rapid movement of the eyes under the eyelids (Rapid Eye Movement). In this phase the brain is very active and the brain stem blocks the motor neurons to prevent us from moving. It is the most singular and most studied phase of sleep, since it is the phase in which we dream. There is great brain activity and it is quite difficult for us to wake up when we are in this phase, as our respiratory rate drops and our blood pressure falls by 10 to 30%.
In the first 10 minutes of this phase it is common to experience rapid and irregular breathing; while in the remaining 30 minutes is when we experience a state of deep sleep and our brain perceives dreams as if they were reality.
The REM phase is the last of the sleep phases and probably the most interesting. The 5 phases of sleep form the sleep cycle. And every night, when we sleep, we repeat the sleep cycle between 3 and 5 times. In addition, each round, the cycle is slightly longer than the previous one, lasting an average of 90 minutes.
Did you know all this about the phases of sleep? In Dupen we are experts in taking care of your rest and we love it, so we are also passionate about giving you tips for a good rest and talk about everything related to your rest and sleep.