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The only reason for your fatigue

Сон как причина усталости

Sleep (Latin somnus) is a natural physiological process of being in a state with a minimum level of cerebral activity and a lower response to the surrounding world, inherent in mammals, birds, fish and some other animals, including insects (eg, fruit fly).

In this article, the famous scientist and trainer James Clear has collected everything that is known to science about the nature of sleep, and gives practical recommendations on how to get better sleep and become more energetic.

On February 13, 1972, Michelle Siffre climbed into a cave in southwestern Texas. The next six months he spent in it, not once during these days not seeing daylight. Siffre was not crazy, but a French scientist and pioneer in the field of chronobiology - a science that studies the work of biological rhythms.

The most famous rhythm is circadian , it regulates the cycles of sleep and wakefulness. Siffre climbed into the cave to find out how this mechanism works. Siffre lived in a tent. The role of the bed was made for him by a wooden pallet. He also had a desk, a chair and a telephone to contact the research team that remained outside.

In his underground there was one light bulb, which always shone with the same soft light, a large supply of frozen food and a couple of tons of water. And the main thing: on him or with him there were no clocks and calendars.

His task was to monitor the body, which does not know whether it is day or night, which means - to sleep or not. So alone in this cave Siffre lived for six months. All this time he tried to understand how his biological clock worked.

Here is what he wrote in his diary: "I finally had a perfect dream! My body now chooses itself, when to sleep, and when - is. It is very important. We are used to 24 hours a day. But the internal clock of our body gives a day a little more - 24 hours and 30 minutes. "Siffr constantly put on himself more and more experiments. And I found the ideal formula in the 48-hour cycle: 36 hours of continuous wakefulness, and then 12 hours of sleep.

The works of Siffra and his followers made him interested in the nature of sleep of scientists from the largest universities - Harvard and Pennsylvania.

Considering the fact that one third of our lives we are asleep, it is difficult to believe that this topic has become seriously of interest to scientists only in recent decades.

Let's start.

How much sleep do you need?

To answer this question, let's look at an experiment conducted by researchers from the University of Pennsylvania and specialists from the University of Washington.

They collected 48 healthy men and a woman who slept an average of 7-8 hours a day. Then they were divided into four groups. The first group - volunteers, who were deprived of sleep for three days in a row. The second group is those who slept only four hours a day. The third group - people who slept for 6 hours per night. Finally, the members of the fourth group had to sleep for 8 hours - no more, no less.

The experiment lasted two weeks. And then all the respondents passed tests for mental and physical performance.

That's what happened.

Those who slept for 8 hours a day remained "cucumbers" and passed the tests as well as before the beginning of the experiment. Meanwhile, those who slept for 4-6 hours, showed a steady decline in cognitive abilities, and the problems grew every day. What is even more interesting, there was no noticeable difference between the members of groups "4" and "6".

Scientists also found that the need for sleep can accumulate.

In a week, every fourth of those groups that were not sleeping, began to "cut out" in random places. After two weeks of experiment, members of the group that slept only 6 hours showed the same deficiency in productivity as those who did not sleep at all for two days in a row.

Let me repeat: if you sleep only six hours a day for two consecutive weeks, your mental and physical abilities are reduced to a level that if you were awake for 48 hours in a row.

The second important observation: the participants of the experiment did not notice that they are losing productivity.

When the participants in the experiment were given the opportunity to independently evaluate their effectiveness, then all of them, as it turned out, overestimated themselves. In other words, we are not able to adequately assess ourselves and our productivity. So, it may seem to us that chronic lack of sleep is normal. Or even that we do not need all 8 hours. But this is not so.

We live our lives in bright offices, conduct social conversations and consume a huge amount of caffeine. Those. we have a lot of tools that allow us to feel awake, although in reality everything is more serious.

Cost of lack of sleep

The irony of the situation is that many of us deliberately deprive ourselves of a normal sleep in order to increase our productivity, in order to be more successful. But in fact we are only hurting our plans.

In the United States alone, research shows that the chronic shortage of workers leads to the fact that their employers lose a total of $ 100 billion a year due to the fact that employees regularly do not sleep.

Grigory Belenky, director of the Research Center for Productivity Studies at the University of Washington, explains: "Unless you are engaged in a job that does not require any mental skills from you, then, depriving yourself of sleep, you trade the time of wakefulness at the expense of productivity" .

This leads us to an important question: how do you understand if you have enough sleep or not?

A wide range of studies have shown that, as a rule, for 99% of people on the planet you need seven and a half or eight hours. This is if we are talking about the optimal values.

Experts agree that 95% of adults in order to live a normal life should sleep every night from 7 to 9 hours. If they sleep less, they will begin to lose their mental and physical performance. Children and the elderly usually need to sleep even more. Meanwhile, people are sleeping less and less.

The Harvard Medical School argues that the average length of sleep Americans have decreased from 9 hours in 1910 to 7 hours today. Dr. Lawrence Epstein of this institute claims that 20% of Americans do not sleep for less than six hours a day.

How to sleep properly

The process, called the cycle of sleep and wakefulness, determines the quality of your sleep.

It has two stages:

  • The phase of slow sleep (deep sleep)
  • The phase of fast sleep (this is when we dream, and when we are easy to wake).

During a slow sleep, the body relaxes, breathing becomes slow and deep, blood pressure drops, the body becomes less sensitive to external stimuli. It's hard to wake up.

This stage is crucial for the restoration and "repair" of the body. During a slow sleep, the pituitary gland actively releases growth hormones. They stimulate tissue growth and muscle repair.

Researchers also believe that the body's immune system also gets a chance to rest during this stage. This dream is especially important if you are an athlete.

It is known that before important competitions LeBron James and Roger Federer sleep 11-12 hours a day. And it's no accident. Researchers at Stanford University have proven that basketball players who sleep more than 10 hours a day show better results in accurately throwing and responding to unexpected situations.

Usually, basketball players sleep 8 hours a day. But if you give them a sleep of ten hours, then the accuracy of three-point shots grows by 9%, and in the sprint by 80 meters they are faster by 0.6 seconds faster than usual. It's a lot. And all because the phase of slow sleep helps us to restore our muscles faster.

Now let's talk about the phase of slow sleep .

At this time, your brain creates dreams and reorganizes information, systematizes it. At this time, neurons also grow rapidly. Therefore, in the morning you have better memory, and in the morning you are easier to learn.

During a "fast sleep", the pulse, pressure and body temperature, on the contrary, increase. You must have such facets from three to five per day. If you deprive yourself of any of these two phases of sleep, your body literally begins to die.

If you lack sleep, you can not restore yourself physically. Your immune system weakens, consciousness becomes hazy. You have an increased risk of contracting a viral infection. You gain weight, you start to develop diabetes, problems with pressure.

A little more - and you will learn what heart disease, mental illness and premature mortality are.

Brief conclusion: you need a slow sleep for physical recovery, fast - for the mental. Since the quality of your sleep worsens over the years, in order to stay young for longer, you need to sleep even more.

Age changes

The Harvard Medical School states that the older you are, the more difficult it is for you to fall asleep. And the worse your sleep copes with its functions.

Based on the above data, we can say that the average 80-year-old man gets a whopping 62% less "slow" sleep than the average 20-year-old guy. And this is one of the reasons why adult cells grow so quickly.

If the elderly have problems with sleep, you can be sure: the process of their aging is now rapidly accelerating. And you need to seek help from a somnologist.

There is no doubt: a good and healthy sleep is the key to protection from premature aging.

How to recover if you do not sleep enough

Specialists from the Harvard Medical School give only one recommendation: you need to sleep during the day . At least a little: 20-30 minutes . This will be enough to help your brain "get together".

When you need to go to bed, and when - to wake up

As you already know, the cycles of sleep and wakefulness are called the circadian rhythm. It determines when you need to sleep.

But here are some common for all points:

  • At 6 am - cortisol levels increase, which helps wake your brain and body.
  • At 7 am - the body stops producing the sleep hormone melatonin.
  • At 9 am - your sex hormones are at the peak of performance.
  • 10 am - peak of your mental activity.
  • 2.30 days - peak for your systems responsible for the motor skills and coordination.
  • 3.30 days is the time when you have the best reaction time.
  • 5.00 a day - the time when your cardiovascular and muscular system works best.
  • 7 pm - time of high blood pressure and fever.
  • 9 pm - time to start the production of melatonin. The body prepares the body for sleep.
  • 10 pm. "You often want to go to the toilet." The body continues to prepare for bed.
  • 2 am. "The time of the deepest sleep."
  • 4 a.m. - The time when you have the lowest body temperature. Waking at this time is especially harmful.

Obviously, all these periods can be slightly different for different people. But they show the general picture.

How to zero?

Circadian rhythms vary depending on how you behave and what you do during the day.

How to reset these "watches" and start them again?

The easiest and tried and tested way: within 30 minutes peer into the bright light. Those. You can spend half an hour outdoors on a sunny day without sunglasses. Even better - wake up at dawn and spend the morning on the balcony.

How to sleep properly. A few recommendations.

Avoid caffeine

If you have trouble falling asleep, eliminate caffeine from your diet. If you refuse to drink a cup of coffee in the morning, you are not able to, then do not drink it at least after noon.

Quit smoking or chewing tobacco

The use of tobacco provokes problems with sleep. How to quit? They say the best book on the subject was written by Allen Carr. It's called "Easy way to quit smoking" .

A bedroom is a room only for sleeping and sex

Spend a lot of time in the bedroom? Look at her TV? This is your main mistake. Remove from the bedroom everything that distracts you: TV, laptop, tablet, smartphone. And also: curtains must be tight. So dense that at night in this room there was absolute darkness.


If you can not get enough sleep, try to do an easy exercise after you get home from work. This will help your body and brain to quickly shut down. Do exercise at least two to three hours before bedtime. Otherwise, you will only harm yourself.


Most people sleep best in a cool room. The ideal range is 18-21 degrees Celsius.


Ideal silence is best. But if you can not muffle the sounds of the street, use white noise. You can turn on a normal fan or install a special application on your smartphone. Another good option is earplugs.


It's a slippery road. Yes, many people drink before bedtime helps quickly turn off. But while alcohol reduces the quality of sleep and delays the phase of "fast" sleep. As a result, your brain rests, but the body does not. That's why in the mornings you often wake up absolutely broken.

Stick to regular sleep

The body loves rituals. Circadian rhythm is the basis of our daily life. Go to bed and wake up at the same time on weekdays and on weekends.

Develop a ritual before bedtime

Avoid the light from the screens of computers, televisions and mobile gadgets at bedtime. The blue light that they radiate suppresses the process of producing melatonin in the body. As a result, you can not fall asleep, and your brain every time when you are in bed, drives around unpleasant thoughts.

In passing, instead of melatonin, the body produces a stress hormone cortisol - and it is the main enemy of your sleep. So before going to sleep, start, for example, just read a book. This is the perfect way to prepare yourself for a night of rest.

Another option is to download the F.lux application, which in the evenings reduces the brightness of the monitor and removes the blue color from its spectrum as much as possible.

You need to have a technique for relaxation

Researchers believe that at least 50% of cases of insomnia are caused by stress. Find a way to deal with it every day. It is checked that such methods as reading magazines, deep breathing exercises, meditation, physical exercises and keeping a diary are working (there you need to write and about what you are thankful to every day).

How to get more energy in the morning

Drink a large glass of water early in the morning. Your body was without inflow of water for six to eight hours. That's why in the mornings you feel so sluggish. Almost always the whole thing is dehydration. The first thing I do when I wake up is drink a big glass of water.

Start the day with sunlight

Sunlight is a new coffee. If you get up early in the morning on the balcony or by the window (from the side where the sun rises) and spend a few minutes there, it will instantly wake you up. And he will ask the brain the right mood for the whole day.

Coffee is a way to wake up on cloudy days and in winter, when you have to get up before sunrise. The rest of the time it's better not to drink it.

In general, why are we all this?

Deficiency of sleep, and even more so, if it is chronic, is the same robber who takes away your ability to work, mind, physical health and a good mood.

Our culture underestimates the importance of good sleep. So try to sleep more. Sounds easy, does not it? What about having a try?