The deep phase of sleep is coming. Deep dream. How long does it take and what is the rate. Distinctive features of slow sleep

The norm of sleep for an adult is 7-8 hours. However, each organism is individual, and therefore the rest time is calculated differently. For some, 4-6 hours is enough to fully restore their vitality, while for others, 9-10 hours of sleep will be optimal. Regardless of which regimen a particular person observes, he has a phase of superficial and deep sleep.

Phase change

When our night journey to the realm of Morpheus begins, we fall into a deep sleep. It lasts approximately 60 minutes, followed by REM sleep. A full cycle, starting from the slow phase and ending with the fast one, takes approximately 90-120 minutes for an adult.

During the night, from 4 to 6 cycles pass, depending on the biorhythms of people. In the first cycle, deep sleep lasts the longest, then its duration decreases. The closer to awakening, the more time we spend in paradoxical sleep, during which the brain actively processes and sorts all the information we have received during the day. In the last cycle, it can take up to an hour.

Stages of the slow phase

Slow-wave sleep is also called orthodox or deep sleep. It is in it that we need to immerse ourselves at the very beginning of the rest in order to fully restore our vital functions. This phase, unlike the fast one, is divided into main stages:

1. Drowsiness - at this time we are just starting to fall asleep, our brain is still actively working, therefore we see dreams, they can be intertwined with reality, it is often at this stage that a person can find answers to questions that remained unresolved during the day.
2. Falling asleep is the stage at which our consciousness begins to turn off, but the brain is still sensitive to external stimuli, it is very important that nothing disturbs a person at this time, even the slightest noise easily wakes him up.
3. Deep sleep is a time when all functions in our body smoothly fade, the body relaxes, but weak electrical impulses still pass through the brain.
4. Delta sleep is the stage of the deepest sleep, when we are most relaxed, at which time the brain stops responding to external stimuli, the body temperature becomes the lowest, blood circulation and respiratory rate decrease.

The Importance of Slow Sleep

Scientists became seriously interested in the study of sleep in the 70s of the last century. In the course of various experiments on volunteers, it was found that depending on the duration of slow sleep, mental and physical indicators change in people.

The test took place at Stanford University and involved football students. If orthodox sleep lasted longer than usual, then endurance and productivity increased in athletes.

It is also known that athletes sleep not for 7-8, but for 11-12 hours a day.

What is the reason for this amount of sleep? The thing is that it is the slow phase that accounts for the process of restoring all the cells of the body. In the pineal gland at this time, growth hormone is produced, which triggers catabolism. This means that protein compounds are not broken down, as during daytime anabolism, but, on the contrary, are synthesized from amino acids. During falling asleep and when immersed in delta sleep, tissues and organs self-repair.

Scientists have also found that if sleep is deep and has the right duration, the immune system works much better. If we do not rest normally at night, then the protective functions of the body will decrease, and we will become susceptible to infectious and inflammatory diseases.

Youth also depends on how well we sleep - if the slow phase does not last as many hours as necessary, the aging process will take place at an accelerated pace.

The effect of deep sleep on intelligence

Scientists have been able to prove that slow sleep affects not only physical endurance, but also the mental abilities of a person. During the experiment, the subjects were given lists of a variety of words, completely unrelated to each other, before going to bed, and asked to remember them. It turned out that people who slept more in the delta stage performed better - they were able to remember more words than those who had shorter deep sleep.

Studies have also proven that artificially depriving a person of a deep sleep phase is equivalent to a sleepless night. If the fast phase tends to be compensated in the following nights, then it is impossible to “sleep” the slow one.

Symptoms such as deterioration in concentration, memory loss, decreased ability to work and other signs of insomnia are also observed if a person does not spend as much time in the orthodox phase as he needs.

No matter how many hours a person sleeps, the slow phase always "opens" his rest. It is very different from REM sleep and has its own characteristics. For example, scientists have proven that, under certain conditions, delta sleep can last longer than usual. This happens if a person is rapidly losing weight, he has a hyperfunction of the thyroid gland (thyrotoxicosis), or the day before he spent a lot of energy on physical work.

A curious fact is that it is in deep sleep that such disorders as sleepwalking, enuresis, and sleep-talking begin to be expressed; a person sees nightmares.

If at this time the sleeping person is awakened, he will not remember anything about his dreams or actions, he will be disoriented in time and space. This condition is associated with a slowdown in all processes in the body, which occurs during delta sleep.

Summing up

Each person needs to sleep as much time as is required for the full recovery of the body.

Deep sleep has many useful functions, it is simply necessary for normal physical and intellectual activity.

Those who want to increase its duration should play sports during the day, and in the evening solve logic puzzles, solve crossword puzzles, or train the brain in some other way. Moderate activity during the entire period of wakefulness will help you fall asleep quickly and have a good rest at night.

2013-03-05 | Updated: 2018-05-29© Stylebody

Scientists have long proven that a good sleep, which includes two main phases - slow and fast - is extremely important for human health and well-being. And this fact must be taken into account when building a daily routine. There is an old folk saying that states that "the morning is wiser than the evening." Indeed, making important and difficult decisions in the morning is much easier than looking at night. In addition, each of us noticed how lack of sleep affects well-being and performance. A sleepless night can lead not only to a sharp decrease in mental activity, but also to headache, weakness, fatigue and other unpleasant symptoms.

Sleep physiology

The human body is designed in such a way that all processes occurring in it are tied to a certain daily time and largely depend on the change of day and night. Sleep and wakefulness constantly alternate and occur at about the same time. And if the normal rhythm of sleep-wakefulness is suddenly disturbed, this negatively affects the work of various human systems and organs. Chronic lack of sleep primarily affects the nervous and immune systems, which can lead to a gradual incapacitation of the entire body.

Wakefulness and sleep are two opposite and, at the same time, interconnected states. When a person does not sleep, he actively interacts with the environment: eats, exchanges information, and so on. During sleep, on the contrary, there is an almost complete disconnection from the outside world, although important processes in the body itself do not stop. It is estimated that sleep and wakefulness in time are in a ratio of 1: 3 - and any deviation from this norm is dangerous to health.

Scientists have been able to capture the changes that occur in the human brain during sleep, using such a research method as electroencephalography. It allows you to make a graphic recording in the form of waves, the decoding of which provides information about the quality of sleep and the duration of its different phases. This method is mainly used to diagnose various sleep disorders and to determine the degree of their negative impact on the body.

When the mechanism that regulates the frequency of sleep and wakefulness is disrupted, various pathological conditions arise, such as narcolepsy (an irresistible desire to fall asleep that occurs during the day), as well as hypersommia (an exaggerated need for sleep when a person sleeps much more than normal).

Sleep is characterized by such a quality as cyclicality. Moreover, each cycle lasts an average of an hour and a half and consists of two phases - slow and fast. In order for a person to get enough sleep, four or five such cycles must go through. It turns out that you need to sleep at least eight hours a day.

The main differences between the phases are:

Duration The slow phase dominates in time. It takes up about 80% of the time of the entire sleep process and, in turn, is divided into four stages. The fast phase takes much less time, and its duration increases in the morning, closer to awakening. Purpose The purpose of the phases of sleep is different. During the slow phase, the internal organs are restored, the body grows and develops. The fast phase is needed to activate and regulate the nervous system, to streamline and process the accumulated information. In children during REM sleep, the most important mental functions are formed - that is why in childhood we so often see vivid, memorable dreams.

Brain activity The differences between the slow and fast phases in terms of brain activity are very curious. If during non-REM sleep all processes in the brain slow down to a significant extent, then in the phase of REM sleep, on the contrary, they are extremely activated. That is, a person is sleeping, and his brain is actively working at this time - therefore REM sleep is also called paradoxical. Dreams People see dreams throughout the cycle, but those dreams that were dreamed during the fast phase are remembered better. The dynamics of dreams also strongly depends on the phase - the slow phase is characterized by restrained dreams, during the fast phase they are more vivid, emotional. Therefore, it is morning dreams that most often remain in memory after waking up.

How is the sleep process going?

When drowsiness rolls over a person and he falls asleep, the first stage of the slow phase of sleep begins, lasting a maximum of ten minutes. Then, as the second, third and fourth stages progress, the sleep becomes deeper and deeper - all this lasts approximately 1 hour and 20 minutes. It is for the fourth stage of the first phase that such well-known phenomena as walking "lunatics", talking in a dream, nightmares, children's enuresis are characteristic.

Then, for a few minutes, there is a return to the third and second stages of slow sleep, after which the fast phase begins, the duration of which in the first cycle does not exceed five minutes. This is where the first cycle ends and the second cycle begins, in which all phases and stages are repeated in the same sequence. In total, there are four or five such cycles per night, and each time the phase of REM sleep becomes longer and longer.

In the last cycle, the slow phase can be exceptionally short, while the fast phase is predominant. And it is not in vain that nature intended it so. The fact is that waking up during REM sleep is very easy. But if a person is awakened when a slow sleep is in full swing, he will feel overwhelmed and sleepy for a long time - it will be possible to say about him that he "got up on the wrong foot."

NREM sleep (4 stages)

REM sleep

When a person plunges into a fast phase of sleep, it is visible even from the outside. His eyeballs begin to actively move, breathing either quickens or slows down, mimic movements of the face may be noticeable. The devices record a slight increase in body and brain temperature, increased cardiovascular activity. During this phase, the process of exchanging information accumulated during wakefulness between the conscious and subconscious takes place, and the energy that the body managed to accumulate during slow sleep is distributed. A person sees colorful dreams that he can remember and retell after he wakes up. Waking up during REM sleep is the easiest and fastest.

How much sleep do you need to get enough sleep?

According to scientists, a person needs to sleep from 8 to 10 hours a day, which equals 4-6 sleep cycles. It should be borne in mind that the duration of the sleep cycle in different people is not the same and, depending on the individual characteristics of the nervous system, can vary from 1.5 to 2 hours. And in order for the body to get a good rest, there should be at least 4-5 such complete cycles. How much a person should sleep is largely determined by his age.

Here is an approximate sleep rate for different age groups:

• The longest sleep in unborn babies in the womb is about 17 hours a day.
• Newborn babies spend in a state of sleep from 14 to 16 hours.
• Babies aged 3 to 11 months need 12-15 hours of sleep.
• One-year-old and two-year-old children sleep 11-14 hours a day.
• It is desirable for preschoolers to sleep at least 10-13 hours.
• The body of primary school children under the age of 13 requires a 10-hour night's rest.
• Teenagers are advised to sleep between 8 and 10 hours.
• The duration of sleep for an adult from 18 to 65 years, depending on the personal characteristics of the body, is 7-9 hours.
• The need of people after 65 years is slightly reduced - they need to sleep from 7 to 8 hours.

How to sleep less and get enough sleep

The quality of sleep is very dependent on what time a person goes to bed. Sleeping until midnight from 19.00 to 24.00 is extremely beneficial. People who are accustomed to falling asleep early feel alert and well-rested, even if they get up at dawn. In this case, a person can sleep less, but still get enough sleep. And the trick is that the value of sleep in a certain period of time is different.

Sleep value table by hour

What time is best to get up in the morning

It is believed that the best time to wake up is from 4 to 6 in the morning. People who get up with the sun are not afraid of fatigue, and they manage to do a lot in a day. But, of course, in order to get up early, you need to develop the habit of going to bed early. In addition, people have different biological rhythms. As you know, people are divided into "owls" and "larks". And if a person is an “owl”, then it is better for him to wake up around 8-9 in the morning.

How to correctly calculate the time of awakening

It is very difficult to make an independent calculation of the time for which you need to start an alarm clock in order to wake up in the REM sleep phase. As mentioned above, each person's sleep phases have an individual duration. Therefore, before carrying out such calculations, you must first contact a medical center so that specialists determine your personal sleep rhythm using special devices.

Although you can calculate the approximate time when it is best to wake up. To do this, take the average duration of the slow phase of sleep (120 minutes), as well as the average duration of fast sleep (20 minutes). Then you should count 5 such periods from the moment you go to bed - this is the time you set the alarm. For example, if you fell asleep at 11:00 pm, then the best time for you to wake up would be between 7:20 am and 7:40 am. If you decide to sleep longer, for example on Sunday, then the time for the correct rise will be between 09:00 and 09:20.

The importance of sleep for the body

• The main purpose of sleep is to allow the body to rest and recover. Prolonged insomnia is fraught with serious health problems. Animal experiments have shown that a complete lack of sleep after a certain time causes hemorrhages in the brain. In people who are chronically sleep deprived, increased fatigue soon occurs, and then problems with the cardiovascular system join.
• Sleep affects the metabolic processes in the body. While a person is in slow sleep, growth hormone is produced, without which protein synthesis cannot occur - therefore, lack of sleep is especially dangerous for children. In sleep deprived people, the cleansing and regenerative processes in the body are also disrupted, since during sleep the cells of the organs are actively supplied with oxygen, and the work of the liver and kidneys, which are responsible for neutralizing and removing harmful substances, is activated.
• During the fast phase, the distribution, processing and assimilation of the accumulated information takes place. By the way, as it turned out, you can’t learn and remember anything during sleep (the method of teaching foreign languages ​​to sleeping people did not justify itself), but the information that entered the brain immediately before going to bed is really remembered better.
• REM sleep contributes to the activation of all neurohumoral processes - the human nervous system is tuned to active work. It has been observed that a lot of nervous diseases appear from lack of sleep.

The effect of sleep on the cardiovascular system

Many of us are accustomed to regularly invigorate ourselves with tonic drinks - strong tea, coffee. Yes, this way you can really cheer up for a short period of time. But then, when the caffeine ceases to act, the person feels even more tired, drowsiness and weakness appear. Therefore, there is nothing better for cheerfulness than normal sleep. People who systematically cut back their sleep time, thereby forcing their body to work with overload and lead it to exhaustion, as a result of which such serious diseases as ischemia, chronic, and so on arise.

The effect of sleep on appearance

Medical scientists unanimously argue that lack of sleep provokes oxygen deficiency in the body and inevitably leads to early aging and a significant deterioration in appearance. A well-rested person, as a rule, can boast not only cheerfulness, but also a fresh look, a good complexion. By the way, metabolic disorders, to which chronic insomnia can lead, often entail an increase in appetite and. Therefore, athletes and actors, for whom it is vital to always be in good physical shape, strictly observe the sleep-wake regime.

Sleep and human behavior

It has been noticed that in people who do not get enough sleep, such negative qualities of character as capriciousness, irascibility, irritability, and aggressiveness become aggravated. And all because their nervous system is not ready for stress and is constantly on edge. But those who sleep well are dominated by an excellent mood and complete psychological readiness to overcome life's problems. Therefore, if your work involves night shifts, be sure to compensate for the lack of sleep during the day. Under no circumstances should the driver be sleepy. A huge number of accidents occurred due to the fact that the sleepy driver was distracted or fell asleep at the wheel.

And, finally, one more function of sleep should be remembered - through dreams, our subconscious mind often sends us hints and insights that help us solve important life problems.

Healthy sleep is one of the basic needs of a person, and indeed of all higher living organisms.. Even plants hibernate during the day, which is confirmed by the study of their functions, which slow down for this period. There are regular reports in the press about people who do not sleep at all. But most often it is a severe pathology that brings a lot of suffering to a person. No wonder there used to be a special torture - sleep deprivation, due to which the person subjected to it eventually either completely broke down or even died. All information about awake people who feel great at the same time turns out to be false.

We need healthy sleep for many reasons.. Firstly thanks to him our body rests. Brain activity, heart activity slow down, muscles relax.

Of course, even during the deepest sleep, organs and systems continue to work, but the load on them is much less than during wakefulness. During sleep, damaged cells are repaired, and almost all the energy that is spent during the day on maintaining various body functions goes to these purposes.

Secondly Sleep is vital for our immunity. It is during the night's rest that T-lymphocytes, the cells responsible for fighting bacteria and viruses, are activated.

No wonder they say that sleep is the best medicine. Bed rest and sleep help to cope with diseases no worse than pills.

Thirdly Thanks to sleep, our brain gets the opportunity, without being distracted by other things, to process all the information received in it during the day. What is not needed is “erased”, and information and impressions that may be useful are deposited in long-term memory. People who suffer from insomnia almost always have memory problems.

Fourth, sleep regulates the level of hormones, including those responsible for our adaptation to the change of time of day and seasons. We sleep at night, because our senses are not adapted to activity in the dark. In the off-season, when the weather and daylight hours change, sleep helps us better adapt to these changes.

Sleep requirements vary from person to person, but on average you need at least 7-8 hours of sleep a day. Usually a person's sleep takes up a third of his life. During this time, we have time to relax, recuperate, and sometimes even recover.

NREM sleep

During this period, the body heals, its cells and energy reserve are restored. In the phase of slow sleep, the respiratory rate decreases, the heart rate decreases, muscles relax. In turn, non-REM sleep is divided into four stages.

The first is drowsiness, when a person half asleep experiences the events of the past day. At the next stage, consciousness turns off, but periodically, about 2-5 times per minute, a state of high auditory sensitivity occurs. At these moments, we easily wake up even from a slight noise. In the third and fourth stages of slow sleep, a person completely turns off and fully rests, his strength is restored.

REM sleep

During this period, the activity of the respiratory and cardiovascular systems increases. At the same time, under closed eyelids, the eyeballs are actively moving. It is in this phase that a person sees dreams.

If you wake up at this time, you will clearly remember their content. In REM sleep, the information received by the brain during the day is processed. It is believed that waking up during this phase is not very healthy, and if this happens, the person feels tired and overwhelmed.

In total, during the period of night sleep, 4-5 complete cycles are replaced. Moreover, the duration of non-REM and REM sleep changes in each cycle: non-REM sleep becomes shorter, and REM sleep becomes longer.

For some people, 6 hours is enough to get a good rest (this is the minimum time that you need to devote to a night's sleep). Others are not enough and 9-10 hours. So how much sleep do you need?

Physiologists believe that the main thing is that sleep should be a multiple of a full cycle, consisting of slow and fast sleep. And these data are confirmed by numerous studies.

In practice it will look like this. The duration of deep sleep is 80-90 minutes, fast sleep is 10-15 minutes. That is, the full cycle takes about 1.5 hours. To get a good night's sleep, you need 4-5 of these full 1.5-hour cycles. It all depends on how tired you are during the day.

Let's say you go to bed at 11 pm. Then you need to wake up either at 5 am or at 7:30. In this case, you will not feel overwhelmed, because the awakening will have to change the phases of REM and non-REM sleep.

Of course, this is just an ideal scheme. It should be borne in mind that on average it will take 10-15 minutes to fall asleep. In addition, depending on your condition, the phases of non-REM and REM sleep may differ in duration.

If you want to always wake up at the right time, you can try to get a special alarm clock. It includes a wristband that tracks your heart rate and gives you an alarm to sound when you're in the transition from REM to NREM sleep - the best time to wake up.

Night rest is divided into periods that differ in ongoing processes. Deep sleep is important, and the adult norm determines how much a person sleeps soundly. From the article you will learn the features and duration of the slow phase.

Night rest is cyclical and is divided into 2 phases: slow and fast. Slow is a deep period from which a healthy person begins to fall asleep. The functioning of the organs slows down, they go into a state of rest, the body is partially switched off, rests and recovers. Then comes the fast phase, during which the brain works and the sleeper dreams. There are muscle contractions, spontaneous movements of the limbs, movements of the eyeballs.

Night rest includes several cycles, each consisting of slow and fast periods. The total number of cycles is 4-5, depending on the total duration of sleep. The first slow phase lasts the maximum amount of time, then it begins to shorten. The fast period, on the contrary, increases. As a result, the percentage by the time of awakening changes in favor of the fast phase.

Duration and norms

How long should a person's deep sleep be at night? The average duration within one cycle can be from 60 minutes to 1.5-2 hours. The normal length of the slow phase is 40-80 percent rest. The fast period will continue 20-50%. The longer the slow phase goes on, the better the person will be able to sleep, the more rested and alert he will feel.

How long does deep sleep last, I understand, but how to calculate the duration? It will not be possible to take measurements with watches and other usual measuring instruments, and even for a person who is next to the sleeping person: it is difficult to determine when the slow phase begins and ends. An electroencephalogram that detects changes in brain activity will allow you to get accurate results.

The rate of deep sleep depends on the age of the person. The average indicators for different age categories are easy to assess if you make a table:

Good to know! In children, the brain goes through a stage of formation, so biological rhythms and processes differ from those characteristic of adults. In infants, the duration of the slow period is minimal, but gradually it begins to increase. Global changes occur up to about two or three years.

Stages of the slow phase

The slow period of sleep, called deep sleep, is divided into four stages:

1. Drowsiness - the beginning of falling asleep, following after a strong drowsiness, a clear desire to sleep. The brain functions, processes the received information. Dreams are possible, intertwined with reality, repeating the events seen during the day.
2. Falling asleep, superficial sleep. Consciousness gradually turns off, brain activity decreases, but it continues to respond to external stimuli. At this stage, it is important to provide a comfortable, calm environment, since any sound can provoke awakening and prevent you from falling asleep and sleeping soundly.
3. Deep sleep stage. Brain activity is minimal, but weak electrical impulses pass through it. The reactions and processes occurring in the human body slow down and fade away, the muscles relax.
4. Delta sleep. The body is relaxed, the brain does not respond to external stimuli, the temperature drops, breathing and blood circulation slow down.

Features and significance of the slow phase

How important is the slow phase? When a person falls asleep deeply, he fully rests. Night is the time for the recovery of the body, which takes place in a slow phase. Replenished energy resources and reserves needed for a full life. Muscles relax, rest after prolonged work, stress and intense exercise. The brain practically turns off, which allows you to systematize the information received during the day, fix it in memory. Cell regeneration occurs, which slows down the natural aging process.

If there is deep sleep, the brain stops responding to stimuli, including sounds. It is not easy to wake a person, which is important for a good rest. If the duration of the fast phase begins to increase, the sleeper will wake up from sounds, his own involuntary sleepy actions, or movements of the person lying next to him.

A full, healthy and normal deep rest period helps to strengthen the immune system, improve the functioning of the immune system. This is important for a frequently ill child, a weakened elderly person, with diseases and at the stage of recovery.

Important! The state of the human body, health and intellectual abilities depend on the duration of deep sleep. Therefore, a good night's rest becomes necessary before important events, during illnesses or during the rehabilitation period.

Changes taking place in the body

During deep sound sleep, a number of changes are observed in the human body:

1. Restoration of body tissue cells. They are regenerated, updated, damaged organs tend to a physiologically correct state.
2. Synthesis of growth hormone that triggers catabolism. During catabolism, proteins are not broken down, but are formed from amino acids. This helps to restore and strengthen muscles, form new healthy cells, for which proteins are building blocks.
3. Restoration of intellectual resources, systematization of information received during the period of wakefulness.
4. Reducing the frequency of breaths. But they become deep, which makes it possible to avoid hypoxia and ensure the saturation of organs with oxygen.
5. Normalization of metabolic processes, stabilization of reactions occurring in the human body.
6. Replenishment of energy reserves, restoration of the necessary performance.
7. Decreased heart rate to help the heart muscle recover and contract actively throughout the following day.
8. Deceleration of blood circulation due to a decrease in heart rate. Organs are at rest, and the need for nutrients decreases.

Causes of violations of the deep sleep phase and their elimination

Changes in the duration of deep sleep are possible. It lengthens with rapid weight loss, after intense physical exertion, with thyrotoxicosis. The period is shortened in the following cases:

• a state of mild or moderate alcohol intoxication (heavy makes sleep deep, but breaks it: it is difficult to wake a drunk person, although rest is not complete);
• stress experienced during the day;
• emotional and mental abnormalities: depression, neurosis, bipolar disorder;
• overeating, eating heavy food at night;
• diseases that are accompanied by uncomfortable manifestations and pain, aggravated at night;
• unfavorable resting conditions: bright light, sounds, high or low humidity, uncomfortable room temperatures, lack of fresh air.

To eliminate sleep disorders, identify the causes and act on them. Sometimes it is enough to change the daily routine, change the sphere of activity and normalize the emotional state. In case of illness, the doctor must, after a comprehensive examination, prescribe treatment. In severe mental disorders, antidepressants and psychotherapy are recommended.

To increase the duration of the slow phase and make deep sleep long, strong and healthy, sleep experts recommend following these tips:

1. You will achieve an increase in the slow phase if you establish and follow a daily routine and maintain a balance of rest and wakefulness.
2. Try increasing your physical activity. It will be useful to lightly exercise before going to bed.
3. To increase the slow phase, give up bad habits.
4. Ensure comfortable conditions in the bedroom: ventilate it, cover the windows with blackout curtains, close the door and protect yourself from extraneous sounds.
5. To increase the duration of the slow phase, do not overeat before bedtime, limit yourself to light snacks.

• In the slow phase, sleep disorders are manifested: nocturnal enuresis (involuntary urination), sleepwalking, sleepwalking.
• If a person who is fast asleep in the deep sleep phase is suddenly awakened, he will not remember dreams, he will feel sleepy, lost. This is confirmed by the reviews of people. At the same time, dreams can be dreamed, but it will not be possible to reproduce them and interpret them with the help of a dream book.
• Experiments have proven that the artificial elimination of the phase of slow sleep is tantamount to a sleepless night.
• Each person has individual norms, features of sleep. So, Napoleon needed 4-5 hours, and Einstein slept for at least ten hours.
• The relationship between deep sleep, the functioning of the endocrine system and body weight has been established. With a reduction in the slow phase, the level of somatotropic hormone responsible for growth decreases, which provokes a slowdown in muscle development and an increase in body fat (mainly in the abdomen).

The norms of deep sleep depend on age and lifestyle. But following some recommendations and optimal nighttime mode will allow you to sleep soundly and feel cheerful after waking up.

Night rest is a natural component of the life of every person, both for an adult and for a child. When people sleep well, they not only elevate their mood levels and feel better, but they also show a significant increase in mental and physical performance. However, the functions of a night's sleep do not end only at rest. It is believed that it is during the night that all the information received during the day passes into long-term memory. Night rest can be divided into two phases: non-REM sleep and REM sleep. Especially relevant for a person is deep sleep, which is part of the slow phase of nighttime rest, since it is during this period of time that a number of important processes occur in the brain, and a violation of this phase of slow sleep leads to a feeling of lack of sleep, irritability and other unpleasant manifestations. Understanding the importance of the deep phase of sleep allows you to develop a number of tips for normalizing it in each person.

Sleep includes a series of stages that regularly repeat throughout the night.

Night rest periods

The entire period of dreams in humans can be divided into two main phases: slow and fast. As a rule, falling asleep normally begins with a phase of slow sleep, which in its duration should significantly exceed the fast phase. Closer to the awakening process, the ratio of these phases changes.

How long do these stages last? The duration of slow-wave sleep, which has four stages, ranges from 1.5 to 2 hours. REM sleep lasts 5 to 10 minutes. It is these numbers that determine one sleep cycle in an adult. In children, the data on how long the night rest cycle should last is different from adults.

With each new repetition, the duration of the slow phase continues to decrease, while the fast phase, on the contrary, increases. In total, during a night's rest, a sleeping person goes through 4-5 such cycles.

How much does deep sleep affect a person? It is this phase of rest during the night that ensures our recovery and replenishment of physical and intellectual energy.

Features of deep sleep

When a person has a slow sleep, he successively goes through four stages, which differ from each other in the features of the picture on the electroencephalogram (EEG) and the level of consciousness.

1. In the first phase, a person notes drowsiness and half-asleep visions, from which one can easily wake up. Typically, people talk about thinking about their problems and looking for solutions.
2. The second stage is characterized by the appearance of sleep "spindles" on the electroencephalogram. The consciousness of the sleeping person is absent, however, he is easily awakened by any external influence. Sleepy "spindles" (bursts of activity) are the main difference of this stage.
3. In the third stage, sleep becomes even deeper. On the EEG, the rhythm slows down, slow delta waves of 1-4 Hz appear.
4. The slowest delta sleep is the deepest period of nightly rest, which is required for the rest of sleeping people.

The second and third stages are sometimes combined into the "delta sleep" phase. Normally, all four stages should always be. And each deeper phase must come after the previous one has passed. "Delta sleep" is especially important, since it is he who determines the sufficient depth of sleep and allows you to move on to the phase of REM sleep with dreams.

Sleep phases make up the sleep cycle

Changes in the body

The rate of deep sleep for an adult and a child is about 30% of the total night's rest. During the period of delta sleep, significant changes occur in the work of internal organs: the heart rate and respiratory rate become lower, the skeletal muscles relax. There are few involuntary movements or they are completely absent. Waking up a person is almost impossible - for this you need to call him very loudly or shake him.

According to the latest scientific data, it is in the phase of deep sleep in the tissues and cells of the body that normalization of metabolic processes and active recovery take place, allowing the internal organs and brain to be prepared for a new period of wakefulness. If you increase the ratio of REM sleep to slow sleep, then the person will feel bad, feel muscle weakness, etc.

The second most important function of the delta period is the transfer of information from short-term memory to long-term memory. This process occurs in a special structure of the brain - the hippocampus, and takes several hours in duration. With a chronic violation of night rest, people note an increase in the number of errors when checking the efficiency of memory, speed of thinking and other mental functions. In this regard, it becomes clear that it is necessary to get enough sleep and provide yourself with a good night's rest.

Deep phase duration

The average sleep duration of a person usually depends on numerous factors.

When people ask about how many hours a day you need to sleep in order to get enough sleep, this is not a completely correct question. Napoleon could say: “I sleep only 4 hours a day and feel good,” and Henry Ford could object to him, since he rested for 8-10 hours. Individual values ​​of the norm of night rest differ significantly between different people. As a rule, if a person is not limited in the recovery period at night, then on average he sleeps from 7 to 8 hours. This interval fits the rest of most people on our planet.

REM sleep lasts only 10-20% of the total night's rest, and the rest of the time the slow period continues. Interestingly, a person can independently influence how long he will sleep and how much time is needed for recovery.

Increasing delta sleep

• Each person must strictly adhere to the regime of falling asleep and waking up. This allows you to normalize the duration of the night's rest and facilitate the morning awakening.

It is very important to maintain a sleep-wake schedule.

• It is not recommended to eat before rest, as well as not to smoke, consume energy drinks, etc. It is possible to limit yourself to a light snack in the form of kefir or an apple a couple of hours before going to bed.
• In order for the deep phase to last longer, it is necessary to give the body physical activity of adequate intensity 3-4 hours before falling asleep.
• Helping you fall asleep faster and get quality sleep can be done with light music or nature sounds. For example, cricket singing for deep sleep is known to be very beneficial. This means that listening to music during the rest is recommended by doctors, however, it is very important to correctly select it.
• Before going to bed, it is best to ventilate the room well and eliminate any possible sources of noise.

Sleep disorders

Woman suffering from insomnia

What percentage of people have to deal with sleep disorders? Statistics in our country show that every fourth person experiences certain problems associated with night rest. However, differences between countries are minimal.

All violations in this area of ​​human life can be divided into three large groups:

1. Sleep problems;
2. Violations of the process of night rest;
3. Problems with well-being after waking up.

What are sleep disorders? These are temporary disorders of any phase of a night's rest, leading to disorders in various areas of the human psyche during wakefulness.

All three types of sleep disorders lead to common manifestations: lethargy, fatigue are noted during the day, and physical and mental performance decreases. A person has a bad mood, lack of motivation for activity. With a long course, depression may develop. At the same time, it is very difficult to identify the main cause of the development of such disorders, due to their large number.

Sleepiness during the day, insomnia at night

Causes of deep sleep disorders

Within one or two nights, sleep disturbances in a person may not have any serious cause and go away on their own. However, if violations persist for a long time, then there may be very serious reasons behind them.

1. Changes in the psycho-emotional sphere of a person, and, first of all, chronic stress leads to persistent sleep disturbance. As a rule, for such a psycho-emotional overstrain, there must be some kind of psycho-traumatic factor that led to a disruption in the process of falling asleep and the subsequent onset of the delta sleep phase. But sometimes it is also mental illness (depression, bipolar affective disorder, etc.).
2. Diseases of the internal organs play an important role in disturbing deep sleep, as the symptoms of diseases can prevent a person from fully resting during the night. Various pain sensations in patients with osteochondrosis, traumatic injuries cause constant awakenings in the middle of the night, bringing significant discomfort. Men may have frequent urination leading to frequent waking to go to the toilet. For these questions, it is best to consult with your doctor.

However, the most common cause of sleep problems is related to the emotional side of a person's life. It is the causes of this group that are found in most all cases of sleep problems.

Emotional disorders and night rest

Sleep and stress are linked

People with emotional disorders cannot sleep because they have increased levels of anxiety and depressive changes. But if you manage to fall asleep quickly, then the quality of sleep may not suffer, although usually the delta sleep phase in these cases is reduced or does not occur at all. Intrasomnic and postsomnic disorders may additionally appear. If we talk about major depression, then patients get up early in the morning and from the very moment of awakening they are immersed in their negative thoughts, which reach a maximum in the evening, leading to a disruption in the process of falling asleep. As a rule, deep sleep disorders occur together with other symptoms, however, in some patients, they may be the only manifestation of diseases.

There is another category of patients experiencing the opposite problem - the initial stages of slow sleep can occur during wakefulness, leading to the development of hypersomnia, when a person constantly notes high drowsiness and can fall asleep in the most inappropriate place. With the hereditary nature of this condition, a diagnosis of narcolepsy is made, requiring special therapy.

Treatment options

Identification of the causes of deep sleep disorders and determines the approach to treatment in a particular patient. If such disorders are associated with diseases of the internal organs, then it is necessary to organize appropriate treatment aimed at the complete recovery of the patient.

If problems arise as a result of depression, then a person is recommended to undergo a course of psychotherapy and use antidepressants to cope with disorders in the psycho-emotional sphere. As a rule, the use of sleeping pills is limited, due to their possible negative impact on the quality of the recovery itself at night.

Sleeping pills should only be taken as directed by a doctor.

It is recommended to take medicines to restore the quality of night rest only as prescribed by the attending physician.

Thus, the phase of deep sleep has a significant impact on the period of wakefulness of a person. In this regard, each of us needs to organize optimal conditions to ensure its adequate duration and complete recovery of the body. If any sleep disorders appear, you should always seek help from your doctor, as a full diagnostic examination allows you to detect the causes of disorders and prescribe a rational treatment that restores the duration of delta sleep and the quality of life of the patient.