Sleep is an inevitable and highly pleasurable state for our bodies. We spend almost a third of our lives in it, an average of 27 years. And that doesn’t stop us from having vague ideas about what happens while we sleep, and ignoring it in every possible way.” Let’s sleep in our coffins!” – This man with bags under his eyes exclaims happily. Yes, maybe. You will learn more about Sleep: Good for Your Brain, Healthy Weight, and Exercise by LCN Outdoors article.
What Is Sleep?
Sleep can be described as a natural, reversible state of the body. At this time, the response to the outside world is reduced and the brain works differently from being awake.
Do you need to sleep? From an evolutionary point of view, desensitization to potentially dangerous stimuli during sleep is a survival risk. However, the fact that almost all animals sleep illustrates its necessity for a normal life.
Although the exact function of sleep remains controversial, it is known to many people.
For example, the fact that all animals sleep despite the risks of surviving in the wild illustrates the evolutionary necessity of sleep for the body.
How Is Sleep Regulated?
Sleep is regulated by two systems: circadian rhythm and homeostasis.
A. Circadian rhythm
The circadian rhythm is also known as the biological clock. It is the periodic release of substances and processes in the body that ensure alternation between wakefulness and sleep.
Circadian rhythms are disrupted during jet lag, a condition caused by jet lag. Fatigue, insomnia, loss of appetite, and other discomforts that accompany jet lag disappear within a few days.
Circadian rhythms are controlled by the suprachiasmatic nucleus located in the hypothalamus, which is part of the brain. The hypothalamus controls the neurohormonal system and the stability of all bodily processes. Wow, what a lot of serious words we learned today!
During the day, the retina of our eyes receives sunlight and transmits signals along neural pathways to the supraoptic nucleus. These signals tell the brain whether it is day or night.
At night, when natural light begins to diminish, the supraoptic nucleus begins to send a series of signals to nerve nodes and hormone-secreting glands. As a result, it stimulates the pineal gland to produce melatonin.
Melatonin is a hormone that transmits the rhythmic information produced by the supraoptic nucleus to organs and tissues. It lowers body temperature, pressure, respiration, and heart rate, and affects the production of other hormones. Melatonin makes us feel sleepy and relaxed as if to suggest that it is time to sleep.
The pineal gland, located in the brain, has a very interesting history. In ancient times, when we were still crawling like reptiles along the coast of the Sea of Cortez, it was actually the “third eye” – an organ at the back of the skull, covered with a thin layer of bone tissue and structured similarly to the other two eyes. Sunlight can penetrate the bone plate and directly affect the hormone secretion of the pineal gland. Interestingly, some lizards and fish have such “windows”. In our case, the pineal gland is pushed deep into the brain.
For example, the white circle on the head of the common lizard is the light-sensitive organ, the “third eye”.
Melatonin secretion starts at dusk and reaches its peak at 4-5 am. After this time, its secretion begins to decrease and ends at dawn.
When we wake up in the morning and our eyes begin to perceive sunlight, our body begins to produce another hormone, cortisol, which promotes waking consciousness. We jump out of bed and face a new day! We hope this is what happens to everyone.
Our circadian rhythm is regulated by two hormones with opposite effects: melatonin acts as a relaxant, while cortisol is invigorating.
B. Internal equilibrium
This is the second system that ensures sleep. Balance here refers to the whole range of mechanisms that regulate the sensations of fatigue and wakefulness. With every hour of wakefulness, our desire for sleep intensifies and these sensations reach their peak just before bedtime. The first thing to brew this “sleep potion” is adenosine.
Adenosine is a compound found in all cells of the body. It has many important functions, such as it is involved in cellular energy metabolism, dilating blood vessels, lowering heart rate, transmitting signals between cells, and reducing inflammation.
But in addition, adenosine slows down the transmission of signals between neurons when stored in the brain during the day. And the longer you stay awake, the more sensitive the neurons become to adenosine. At some point, you start to “drift off” – there’s an uncontrollable lethargy and a great sense of fatigue. And you may even fall asleep at the opening of the Olympics.
Adenosine builds up in the brain, slowing down the transmission of signals between neurons. This is part of the reason why we end up feeling lethargic and tired at the end of the day.
In addition to adenosine, norepinephrine, octreotide, acetylcholine, GABA, and thalamus also play a role in wakefulness and sleep.
- Norepinephrine and octreotide keep you awake during the day.
- Acetylcholine is involved in the process of falling asleep and waking up.
- GABA (gamma-aminobutyric acid) has an inhibitory effect on nerve conduction, thus promoting sleep.
- The thalamus is the part of the brain that blocks sensory signals during sleep. And that’s fine: it prevents us from smelling, hearing, and feeling changes in temperature while we sleep.
Stages Of Sleep
Sleep is divided into two main stages.
NREM (Non-rapid eye movement sleep) represents non-rapid eye movement.
REM (rapid eye movement) represents rapid eye movement.
Non-rapid eye movement
NREM is divided into several stages.
- NREM-1 – Sleep, or very light sleep.
- NREM-2 – light sleep.
- NREM-3 – deep or slow sleep.
A. NREM-1 – falling asleep, or very light sleep
What is happening in the body? The heartbeat and breathing rate gradually decrease, the eye movements calm down, and the body temperature begins to drop. Slumberers often imagine how they fall and jerk, and may wake up from it.” So you grow up sleeping,” my grandmother used to say when I was a child.
If a person is woken up during this stage, they may say they weren’t asleep at all. The duration of the stage. This is a transition period from wakefulness to sleep. NREM-1 accounts for about 5% of total sleep time and lasts from 1-to 5 minutes.
B. NREM-2 – light sleep
What happens in the body. Heart rate, respiratory rate, and body temperature drop more severely. Eye movements stop. About the EEG. Periodic sharp bursts of coordinated neural activity can be seen – a “sleep vortex.
The length of the phase. NREM-2 takes a cycle of 10-60 minutes.” Light sleep” takes up almost half of the entire sleep period. This is the longest stage.
The role of the stage. This is an important stage of sleep that helps the body enter the “deep sleep” and rapid eye movement stages. During “light sleep”, short-term memories stored in the hippocampus (a part of the brain) are transferred to long-term storage in the cerebral cortex. stage NREM-2 may also be important for general motor-motor learning.
If there is too much “light sleep,” you are likely to wake up feeling weak and tired. During the day, you may have problems concentrating and remembering information. The body and brain do not fully recover: Because “light sleep” lasts so long, there is simply no time to move on to other stages.
Excessively long “light sleep” is accompanied by frequent awakenings, interrupted sleep, and an inability to rest. This repetitive condition can lead to insomnia and health problems.
C. NREM-3 – deep or slow-wave sleep
What happens in the body.” Deep sleep” is the period when we sleep most soundly. Your heart rate, respiratory rate, and body temperature are all lowered to the lowest possible level and your muscles are completely relaxed.
The length of the stage. the cycle length of NREM-3 is 20-40 minutes. The first cycle after falling asleep will be the longest. After that, their duration decreases.
The role of the stage.” Deep sleep “is important for strengthening the immune system, repairing muscles and other tissues, and increasing energy resources for the next day. Although brain activity is reduced, there is evidence that “deep sleep” promotes insight – insight, creativity, and memory.
If total sleep time is shortened, the NREM-3 stage is shortened first. In addition, as we age, the amount of “deep sleep” naturally decreases.
D. REM or REM Sleep
What happens in the body. In this stage, periods of lack of muscle tone are replaced by rapid eye movements – under closed eyelids – and muscle twitching. The respiratory rate also increases, and heart rate and blood pressure increase to levels close to those seen during wakefulness. During “rapid eye movement sleep” it is common to dream, but at this time your muscles are temporarily paralyzed – and very well: this bodily mechanism prevents you from physically responding to dreams. That’s why REM sleep can also be called “the state of an active brain in a paralyzed body.
The duration of this stage.” REM sleep also occurs in cycles of 10-60 minutes. The first occurs about 1.5 hours after falling asleep. Several REM cycles may occur during sleep, with intervals of about 90 minutes. Their duration increases in the second half of the night.
The role of stages.” REM sleep plays a large role in the process of learning, memory and helps our brain consolidate – strengthen, merge – and process information. This stage is also prescribed to play a large role in the formation of emotional and affective memories.
How Much Sleep Do You Need?
While sleep needs vary from person to person, there are general recommendations for different age groups. For example, the Mayo Clinic in Minnesota, USA, one of the world’s largest private medical and research centers
- Infants: 4 to 12 months – 12 to 16 hours per day.
- Children: from 1 to 2 years – 11 to 14 hours per day, including naps.
- Preschoolers: from 3 to 5 years old – 10 to 13 hours per day, including naps.
- Lower school students: from 6 to 12 years old – 9 to 12 hours per day
- Adolescents: 13 to 18 years old – 8 to 10 hours per day.
- Adults: 7 to 9 hours per day.
What Happens When We Sleep?
A. Our brain
Each individual stage of sleep helps regenerate brain cells and optimize brain function during the day. The brain visibly reorganizes itself, creating new pathways that help absorb new information and consolidate memories, forming long-term memories.
In this way, sleep helps the brain to learn, remember, think logically and make choices. In addition, sleep clears the brain of byproducts.
There is some folk wisdom about this: the idea that you should sleep before an exam, that “you’ll be better in the morning,” or that you should “get some sleep.
B. Our heart
Blood pressure and heart rate drop when you sleep, which makes it easier for your cardiovascular system to function. If you don’t get enough sleep, these values will stay higher for longer periods of the 24-hour sleep-wake cycle. This increases the risk of coronary heart disease – angina, myocardial infarction, and coronary atherosclerosis – as well as arrhythmias, stroke, and hypertension.
C. Immune system
The immune system is a shield against diseases and infections. During sleep, there is an increased release of anti-inflammatory substances, cytokines, and hormones that benefit immune function, such as somatostatin, melatonin, prolactin, and leptin.
This effect of sleep on the immune system has also been confirmed by studies. For example, in the midst of this, shorter and more efficient sleep makes a person more susceptible to rhinovirus. Not getting enough sleep is a sign of irresponsibility to your health.
D. Insulin and type 2 diabetes
Insulin is a hormone that regulates the amount of glucose in the blood, delivering it to cells to supply energy. After a meal, glucose levels rise, so the body produces more insulin.
Sleep deprivation can lead to insulin resistance – cells that are insensitive to insulin. In this case, the cells are unable to absorb the glucose that insulin is trying to deliver. Glucose is “floated” in the bloodstream, causing many problems. This leads to the development of type 2 diabetes.
E. Healthy weight
Our bodies constantly produce hormones that regulate appetite. These include gastrin, which makes you feel hungry, and leptin, which tells you that you are full.
Lack of sleep raises gastrin levels and lowers leptin levels. You may have noticed this: if you don’t get enough sleep, burritos and cake can become unbearable. If you don’t get enough sleep, you can keep snacking throughout the day and never feel full. This could be the effect of gastrin.
In addition, the constant fatigue caused by lack of sleep greatly reduces your motivation to eat right and exercise.
Therefore, when given the choice between “training” or “sleep”, choose “sleep” and then you can work out. The choice between “getting enough sleep” and “training” is simple: get enough sleep first, then go to training.
F. Growth and Development
Growth stimulating hormone, or “growth hormone,” has many growth-related functions that have pleasant effects on athletes. For example, it increases the synthesis of proteins in the body, inhibits their breakdown, prevents the deposition of subcutaneous fat, and regulates bone density.
Here, we are interested in gonadotropin because its production peaks exactly during the NREM-3, or “deep sleep” phase. Therefore, only adequate sleep can ensure a high-quality recovery after exercise.
G. Intestinal tract
The gut microbiota – a collection of bacteria, viruses, and fungi – is approximately 2.2-4.4 lbs (1-2 kg) and plays an important role in our physiology. It is formed during fetal development and changes throughout our lives in response to diet, lifestyle, and medication intake. Our relationship with the gut microbiota can be described as mutually beneficial: we have become home and breadwinner for all these microbes, and they also help us with digestion, the metabolism of bile acids and other substances, and the synthesis of some vitamins and hormone-like substances.
What does sleep have to do with this? In fact, the activity of the gut microbiota is cyclical and these cycles depend on alternating periods of feeding-wake and hunger-sleep. When sleep is lacking or of poor quality, the balance of microbiota composition or function can be disturbed. We may experience intestinal disturbances – bloating, diarrhea, constipation, experience impaired health – weakness, fatigue, or experience metabolic disorders. Just drinking yogurt won’t work; you have to get some sleep!
H. Emotional condition
Sleep plays a vital role in emotional processing. During “deep” and REM sleep, there is more emotional memory formation, empathy-empathy-behavior, recognition of fears and threats, processing of positive and negative experiences, and the formation of “emotional reactivity”-the speed of emotional responses the next day.
In addition to dealing with emotions, REM dreams are also considered to be inner psychotherapists: dreams about a disturbing topic bring us “alive” and find solutions to problems.” Sigmund Freud said, “The more bizarre a dream seems to us, the more profound its meaning.
You yourself may have experienced emotional disturbances due to lack of sleep: irritability, mood swings, increased tension, decreased energy, and confidence. In addition, poor sleep can alter our facial expressions, making them more difficult for others to read and less attractive, which can lead to socialization problems.
In addition to physical health, dreams ensure emotional well-being. Dreams are also used to “live” exciting situations and to find solutions to problems.
I. Sleep and exercise
Sleep, by allowing the body to rest and starve, ensures optimal physical and behavioral recovery processes.
What happens when athletes don’t give enough attention to sleep? Let’s look at the research.
- 30% overall decrease in cycling performance after restricting habitual sleep.
- Increased cycling time, impaired psychomotor alertness, increased perceived stress in athletes and worsened mood after sleepless nights.
- reduced results on a 2 mile (3.2 km) exercise bike ride after an evening workout and 2.5 hours of sleep in the morning.
- Reduced aerobic performance and jump test results and impaired cognitive-mental-function after 4 hours of sleep and sleepless nights.
But these studies were short-term, with 1-4 nights of sleep deprivation. After this, you can quickly recover and get back into exercise.
On the other hand, chronic sleep deprivation can have a more serious impact on exercise performance, especially with prolonged and frequent exercise and equally frequent sleep deprivation.
Sleep deprivation interferes with learning new movements, which makes perfect sense for climbers, namely the perception of pain. It reduces immunity, which is important for recovery from hard training and interferes with the quality and speed of muscle recovery.
Sleep deprivation can also alter the daily cycle of glucose metabolism and hormone production. This can lead to changes in appetite, meal frequency and frequency, protein synthesis, and subcutaneous fat synthesis.
All of these can ultimately have a negative impact on an athlete’s nutritional, metabolic, and hormonal status and therefore may reduce performance.
Therefore, 7-9 hours of sleep should be included in the athletic schedule along with training, stretching, and myofascial release. Getting enough sleep is just as necessary in an athletic schedule as training, stretching, and myofascial release.
How To Improve Sleep?
All aspects that affect your sleep can be divided into several factors.
- Sleep conditions.
- Personal well-being.
- sleep schedule. Always go to bed and get up at the same time, even on weekends.” Catching up on Saturdays and Sundays doesn’t work. It will only disrupt your regime. The biggest change in sleep schedule is 1 hour. This is the most important point of a healthy sleep plan.
- This bed is for sleeping and sex only. Choose another place in the house to watch TV, read, eat and work.
- Regular physical activity. Regular exercise improves sleep quality by reducing the time spent falling asleep and increasing “deep sleep” and sleep in general.
To quote the World Health Organization physical activity guidelines: “Adults should engage in at least 150-300 minutes of moderate-intensity aerobic physical activity per week or at least 75-150 minutes of high-intensity aerobic physical activity per week. This is approximately 25 minutes per day.
But remember, the best time to exercise is in the morning and afternoon. Quiet activities, such as yoga or stretching, are appropriate in the evening. Exercise less than an hour before bedtime can interfere with falling asleep quickly and reduce sleep efficiency.
Complete caffeine intake 8-10 hours before bedtime.
Limit alcohol consumption to no more than 1 drink per day for women and men over 65 years of age and no more than 2 drinks per day for men 65 years of age and younger. Finish drinking 3 hours before bedtime.
Do not use alcohol as a sleeping pill. Wine, beer, or cocktails can help you relax and feel sleepy. But with alcohol, you lose the opportunity to go into deep restorative sleep.
Eat your last full meal 3 hours before bedtime. If you feel hungry later in the evening, you can have a light salad, cottage cheese, fermented dairy products, eggs with salad leaves, or other protein or fermented dairy products in small portions.
However, during the day, stick to a balanced and varied diet with plenty of fresh vegetables, fruits, whole grains, and low-fat sources of protein.
A4. Daytime naps
If you’re not getting good sleep, this can be a great way to get a quick “reset” or rest during the day. But be aware of two conditions.
- Sleep for 15-20 minutes. The longer you sleep, the more likely you are to wake up broken.
- Sleep during the day until 3 pm. Sleeping in the afternoon may prevent you from falling asleep and getting a good night’s sleep.
If you don’t get a good night’s sleep, you can also use a short nap before training.
B. Sleep conditions
The room where you sleep should be as dark as possible: no light sources and no blackout curtains. The slightest glow – computers, phones, light bulbs, night lights – can disrupt melatonin production and worsen sleep quality. This rule also applies when camping: you will sleep better if your tent has a dark awning and stands in the shade. If it is not possible to create a completely dark sleeping space, you can use an eye mask. This can happen in camping in the tundra region in extreme daylight. An eye mask can act as an eye cover.
B2. Room temperature
During sleep, our body temperature drops. A cooler room will help this process, while a room that is too hot will hinder this process and thus reduce the quality of your sleep. The optimal temperature inside the room or sleeping bag is 59-68 °F (15-20°C).
This is a normal urban problem – road-noise, noise from neighbors, noise from the street. Or your sleep patterns don’t match those of your roommate or tenant. A good solution is earplugs, micro earplugs or “white noise” – a mix of sounds that have the same intensity at all frequencies.” White noise can be found in all music apps, and in nature, it is the sound of a river or the wind.
We spend a third of our lives in bed. A good reason to give this place the attention it deserves. Choose high-quality and comfortable mattresses, pillows, blankets, and sheets. So you can lie in bed and enjoy a restful, restorative sleep. In camping conditions, a comfortable rug and a warm sleeping bag will do the trick. If you can’t sleep peacefully without a pillow, you won’t have any extra pillows on your trip – feel free to bring them along, a good compact and lightweight model shouldn’t pull away many shoulders. We describe how to choose one here.
If you can’t sleep comfortably without a pillow, feel free to take one with you on your camping trip. It’s better to carry an extra 200 grams in your backpack than to not have enough sleep.
C. Personal well-being
C1. a diary
Keep a notebook by your bed. If you can’t sleep because of a worry, then write it down and put it off until tomorrow. This will help you calm down and get to sleep.
Or you can use it as a gratitude journal. Write down all the good things that happened to you during the day and who you are grateful for. This practice helps keep you in a positive mood, soothes your emotions, and helps you fall asleep faster and more peacefully.
C2. Screen time
Put away your phone and get up from behind your computer 1-2 hours before bedtime. The blue light from your device’s screen prevents your brain from releasing melatonin, the hormone that makes you feel sleepy. This can prevent you from falling asleep quickly. When camping, bright light is usually not a problem, but it’s better to use dim lights or red LEDs if you have such lights installed in your lantern before sleeping in your tent.
C3. 20-minute rule
If you can’t fall asleep after 20 minutes in bed, get up and do something relaxing. For example, read a book, listen to relaxing music, do breathing exercises or meditate until you feel sleepy. The main condition is that you have to leave your bed, or better yet, move out of your bedroom and into another room. This way you won’t associate your bed with a tired attempt to fall asleep.
If you can’t fall asleep after strenuous exercise, a long walk or habilitation, remember the 20-minute rule. Instead of lying in bed in pain trying to fall asleep, get out of bed in the cabin or get out of the tent, look at the stars, breathe, and do some stretching exercises.
Spend an hour before bedtime engaging in a quiet, enjoyable activity. This can be reading, light stretching or yoga, breathing exercises, gratitude journaling, aromatherapy, or any other ritual. If you can’t fall asleep within 20 minutes, get out of bed and do any of the above until you feel sleepy.
How Do I Track My Sleep?
This is a sleep study that measures brain activity – EEG, eye movement – EEG, muscle activity – EMG, and heart activity – ECG. Polysomnography provides information about the stages of sleep and is considered the gold standard for assessing the quality and quantity of sleep. In addition, total sleep duration, sleep onset latency, number of awakenings after sleep onset, sleep efficiency, sleep fragmentation index, duration of each sleep stage, and percentage of sleep stages are determined. Polysomnography can be expensive and time-consuming and is primarily used to assess clinical sleep disorders in the hospital setting.
Polysomnography involves measuring brain activity – EEG, eye movement – EEG, muscle activity – EMG, and heart activity – ECG. It is the “gold standard” for measuring sleep. Polysomnography is performed in a hospital setting.
B. Medical studies
This is a sleep study using an activity recorder, which is a device worn like a watch. The kinetograph continuously records body movements with a built-in accelerometer, and the data is usually stored at 1-minute intervals. A diary was also collected in which participants recorded the start and end dates and times of all sleep events – night and day. Behavioral mapping is useful for understanding sleep patterns: total sleep duration, delay in sleep onset, awakenings after sleep onset, and sleep efficiency. Unlike polysomnography, it is much easier to perform. Activity loggers make it relatively easy to collect data over a fairly long period of time – for example, two weeks.
Actigraphy is performed using a wristwatch-like device. An internal accelerometer records body movements.
C. Self-observation of sleep
Analysis in the form of a diary can be very helpful in improving sleep. Write down the following points on a piece of paper for two weeks.
- the time you go to bed.
- the time you actually fall asleep.
- how many times do you wake up during the night.
- how often – each time – do you fall back asleep.
- the time you wake up in the morning.
- how many times have you slept during the day and for how long.
- the medications you have taken.
- how much caffeine or alcohol you drank.
A self-examination of this information may reveal some unexpected sleep disorders.