Medically reviewed by Raj Dasgupta, MD — By Daniel Yetman on October 22, 2020
Getting a full night’s sleep not only feels good, but it also improves your mental performance and boosts your overall health. Most adults need more than 7 hours per night for optimal well-being. Children and teenagers need even more to support their development.
Teens should sleep 8 to 10 hours per night, grade-schoolers 9 to 12 hours, and preschoolers 10 to 13 hours.
Many people wonder if it’s possible to “hack” their sleep so that they spend fewer hours in bed but still wake up feeling rested and productive. The short answer is yes and no — but mostly no.
The quality of your sleep plays a role in determining how rested you’ll feel when you wake. Improving your sleep quality can reduce the number of hours you need to spend in bed.
However, even if your sleep quality is great, sleeping for fewer hours than what’s recommended is detrimental to your health and mental performance. You may be able to do it for a few days, but eventually, the lack of rest will catch up with you.
Keep reading to find out why it isn’t possible to feel rested after getting only 4 hours of sleep per night over a long period. We’ll also look at why some people seem to be able function off much less sleep than others.
For most people, 4 hours of sleep per night isn’t enough to wake up feeling rested and mentally alert, no matter how well they sleep.
There’s a common myth that you can adapt to chronically restricted sleep, but there’s no evidence that the body functionally adapts to sleep deprivation.
Also, people who exercise regularly often need more than the minimum recommended hours to give their bodies time to regenerate from the additional physical stress.
A 2018 study that examined the sleep habits of more than 10,000 people found that regularly getting 4 hours of sleep per night was the equivalent of adding 8 years of aging to the participants’ brains.
Getting fewer than 7 hours of sleep per night over a long period may increase your risk for developing complications like:
There’s one caveat when it comes to how much sleep you need: Everybody’s body is different, and some people can thrive off fewer hours of sleep than others.
Scientists have found a rare mutation of the ADRB1 gene in people who are able to feel rested with less than 6.5 hours of sleep per night without any apparent health consequences.
If you carry this gene mutation, it’s possible that you may feel rested even if you consistently sleep less than the recommended number of hours.
Polyphasic sleep refers to sleeping multiple times in a 24-hour period instead of once per night.
There are many different polyphasic techniques. One of the most common programs involves taking six 20-minute naps spaced equally throughout the day for a total of 3 hours a day.
Many people claim that polyphasic sleep allows you to sleep more efficiently and achieve the same amount of rest in fewer hours. However, there’s no medical evidence that polyphasic sleep is better than traditional sleep.
Sleep deprivation on polyphasic programs likely has the same negative health consequences as other forms of sleep deprivation. However, there’s limited research on these types of programs, since the vast majority of people who follow polyphasic programs only stick with them for a short time.
Chronically cutting your sleep short isn’t a good idea, but life gets busy and sometimes sleeping adequately isn’t possible for a few nights. The more nights you limit your sleep, the more “sleep debt” you’ll rack up. As with financial debt, the more sleep debt you have, the harder it is to pay it off.
There’s no magic way to increase your energy while cutting your sleep. However, the following techniques may help you get through short-term periods of sleep deprivation.
If you’re experiencing the following side effects, it’s likely a sign that you need to sleep more. It’s a good idea to prioritize rest for the next few nights until you notice your mental function return to normal.
Your body cycles through four stages of sleep throughout the night.
One cycle takes about 90 minutes.
During a typical night’s sleep, you’ll cycle through each stage four to six times. If you’re limiting yourself to 4 hours of sleep, you’ll only have time to cycle through these stages twice.
The sleep stages are:
Most adults need at least 7 hours of sleep per night to wake up feeling rested and mentally fresh.
Limiting your sleep raises your risk for developing many health problems such as diabetes, depression, or cardiovascular disease.
If you have to limit your sleep for a few days, you can potentially increase your energy by spending time in the sunlight, taking short naps throughout the day, and performing light exercise.
For more sleep support, check out our sleep shop.
Last medically reviewed on October 22, 2020
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(2020). Physiology, sleep stages.Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available.
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Oct 22, 2020
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Medically Reviewed By
Raj Dasgupta, M.D.
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Medically reviewed by Raj Dasgupta, MD — By Daniel Yetman on October 22, 2020
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In this day and age of overtasking and multitasking, lots of people wish they could shave some hours off of their nightly need for sleep.
If that sounds like you, unfortunately, your body and brain may not agree with your wish.
Most adults feel best when they get somewhere between 7 and 9 hours of sleep a night. Less than that, and you could experience negative effects from sleep deprivation, such as irritability, a weakened immune system, and memory loss.
The amount of sleep you need varies and is based on a number of factors, including age and genetics. Some people are genetically predisposed to be short sleepers, and only require 4 or 5 hours of sleep a night. Others are long sleepers, who feel best when they get 9 or more hours of sleep.
The amount of sleep you need, and how you feel upon waking, may also be clues to your overall health. If you’re worried that you’re sleeping too much, can’t seem to fall or stay asleep, or feel tired even after a full night’s sleep, talk to your doctor.
You can’t change your genes and become a short sleeper, but you can optimize your sleep habits and routine.
This isn’t quite the same thing as training your body to need less sleep, but it is an effective way to make the most out of the sleep you get. It will also help you zero in on the exact amount of sleep you need in order to feel your best.
Time spent tossing and turning is wasted time. You can shave off the hours you spend trying to fall asleep through better sleeping and waking habits. Here are some tips to try:
The goal here is to train your body to fall asleep when you’re tired. One way to do that is by giving yourself ample time to relax at night before lights out. Try turning your home, or at least your bedroom, from a brightly lit, daytime environment to a cozy and restful nighttime one.
Around an hour before you want to fall asleep dim the lights, and begin transitioning to your sleep routine. This might include washing your face, brushing your teeth, and getting out of work clothing into pajamas.
Anything with a screen should get shut off during your winding-down time.
This includes:
The short-wave emissions of artificial blue light that are generated by these devices inhibit the release of melatonin, a hormone that induces sleep. One exception to this rule are e-ink e-readers, such as the Kindle Paperwhite.
Alcohol is a sedative that can knock you out cold, or at least help you fall asleep quickly. However, it metabolizes in your system over the course of several hours, resulting in sleep disruption and poor sleep quality. Drinking alcohol can also dehydrate you and cause grogginess or a hangover, which affect your ability to wake up refreshed.
Some people can down an espresso after dinner with no ill effects. Others can’t drink coffee after 3:00 p.m. Caffeine stays in your system from 4 to 6 hours. If you suspect that your late-day cola is keeping you up at night, eliminate all forms of caffeine from your diet at least 6 hours before you want to be asleep.
The temperature of your bed and bedroom can affect the quality of your sleep. Being too warm at night adversely affects REM sleep, the period during which your brain is most active. Try turning the thermostat down to around 60 to 68°F (15 to 20°C), or opening up a window to get a better night’s sleep.
External noise, such as traffic or boisterous neighbors, can keep you awake or jolt you awake. If you live in an area where noise is a problem, reduce it by using ear plugs, a white noise machine, or both.
Dancing till dawn on weekends can be tons of fun on occasion, but maintaining the same sleep and wake times 7 days a week will help you fall asleep faster and wake up feeling more refreshed.
Most people hold onto their pillows far longer than they should. The lifespan of the average pillow is 1 to 2 years. Longer than that and they lose their shape, becoming lumpy and unsupportive of your neck and head.
This can adversely affect sleep.
Plus, they tend to fill with dust mites over time. Another good reason to treat yourself to a new one, especially if you have allergies.
Shop all expert-verified pillows in our sleep shop to work toward your best snooze possible.
If your mattress is uncomfortable, old, or lumpy, your ability to get a good night’s sleep will be compromised. The lifespan of a mattress varies based on quality and other factors. In general, most mattresses should be swapped out for a new one every 7 to 10 years.
Want suggestions? Browse our market, filled with editor-trusted and expert-verified mattress recommendations.
Eating late at night can disrupt your ability to fall asleep, especially if you eat heavy or fatty food, like pizza or cake. If you are hungry or crave a little something, reach for these sleep-inducing foods instead.
A warm soak in the evening helps your muscles relax, letting you rest more effectively and quickly.
Consider soaking about 90 minutes before you hit the sheets.
A gently scented room may help you unwind and fall asleep faster. Try these essential oils, which have been linked to better sleep.
Losing yourself in a good story can help you transition from your day-to-day reality to a restful, slumbering state. Reading helps you reduce stress, letting you fall asleep faster.
If you’re addicted to your snooze button, give up those extra 10 minutes to get into a better routine. This may be especially true if you wake up naturally before your alarm goes off. Your body may be telling you that you don’t need any more sleep. You can reinforce that by getting out of bed and starting your day.
If you awaken in a dark room, open the blinds and let light in. Natural light will help you wake up, and may reduce your need for more sleep.
Establishing a reliable morning pattern of behavior can help you feel and be more productive, making you eager to get out of bed in the morning.
Exercising has been shown to reduce insomnia and improve sleep quality. Exercising early in the day may be more beneficial than exercising at night for many people. Try experimenting with the time of day and type of exercise you do.
A cool shower is invigorating, and can help you wake up energetically. Anecdotally, some people also feel that drinking cold water first thing in the morning helps them wake up more fully. Try having a cold glass of water before you reach for your first cup of coffee and see how you feel.
If you consistently need to sleep more than 8 or 9 hours a night, you may be oversleeping. This can be caused by a number of conditions, including depression, thyroid conditions, and heart disease. Some medications may also cause oversleeping.
Oversleeping is sometimes temporary, and may be your body’s reaction to an oncoming illness.
If you oversleep nightly for a prolonged period of time, it may be time to visit your doctor.
Everyone has a bad night’s sleep every now and then, where you wake up feeling tired or exhausted. If you rarely or never feel rested in the morning, you may be experiencing short periods of wakefulness that you’re not aware of, due to alcohol use, indigestion, or other issues.
You may also have a condition such as restless leg syndrome or sleep apnea. Try improving your nighttime routine and see if it helps you wake up feeling refreshed instead of tired.
If you are unable to change your sleeping habits, and find yourself unable to get out of bed with less than 10 or 12 hours of sleep a night, talk to your doctor.
You should also see your doctor if you always feel tired in the morning, regardless of how much sleep you had.
Chronic insomnia is a medical condition that can be treated.
If lifestyle habits are not enough to improve the quality of your sleep, a doctor may be able to help.
It may not be possible to train your body to need more sleep. However, good sleep hygiene and a proactive morning routine can help you get the most out of sleep, and reduce the amount of time you spend trying to fall asleep.
Denis Volkhonsky, the author of the Above My Head Telegram channel, talks about how to improve my sleep.
329 956 views
I used to sleep nine hours a day and didn't get enough sleep. I went to bed late and got up very late. Life has been a struggle with sleep. I associated it with some disease unknown to modern medicine.
The last couple of years I have greatly improved the quality of my sleep. Now I get up early, sleep about seven hours and feel good. In this article, I want to share methods that have helped me get better sleep and start getting enough sleep.
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Sleep mode
Most articles about sleep begin with a recommendation to get up and go to bed at the same time. The rest of this recommendation ends. For me it doesn't work. I would be glad, but during the week my central nervous system is loaded differently. Different days require different sleep times. After a workout, you want to sleep more. When you are in a calorie deficit, you want to sleep less. Therefore, I do not require constancy from the body.
What really helped me was going to bed and getting up earlier. Once upon a time I fell asleep between one in the morning and four in the morning, and woke up no one knows when. I was one of those people who at the mention of the first couple at the university spoiled the mood. nine0003
Now I wake up between five and seven in the morning and go to bed before midnight. This mode is more natural for the body. I feel much better about it.
One day is enough to change the regime. No matter what time you go to bed, wake up the next day at six in the morning.
In the evening of the same day you will be very sleepy - go to bed. Congratulations, you are a lark. Don't forget to set your alarm for 6 a.m. the next day.
Food
nine0013Nutrition is a powerful tool that can be manipulated to influence sleep. Consider two extreme states: "hunger" and "I overeat."
Our body is designed for survival. Hunger is stressful for him. In order to survive, you need to eat. The brain for this activates your search activity. You become more energetic. To sleep less, you need to eat less.
On the contrary, if you are in a state of "I overeat", then it will be easier for you to fall asleep: from the point of view of evolution, you should be put into energy-saving mode. Part of the energy is now directed to the digestion of food. Overeating at night - got a quick fall asleep in exchange for guilt. Everything is fair. nine0003
Caffeine and alcohol
I avoid anything that contains caffeine a few hours before bed.
Coffee, tea, Coca-Cola, chocolate, energy drinks, pre-workout complexes - all this is desirable to exclude after three in the afternoon.
If I really want to go to bed, I drink herbal tea. For example, Ivan-tea or wild rose. They are tasty and do not contain caffeine. And rosehip also improves immunity.
From left to right: Ivan tea, Armenian herbs, wild rose
I don't drink alcohol: it doesn't let my body get enough sleep. You can fall asleep from it quickly, but do not rely on deep sleep. The body will remove alcohol from the body, there is no time for sleep.
Training
Any training is stressful. You have arrived at the gym. Lie down under a heavy barbell. The body thinks you will die soon. To cope with difficulties, it releases stress hormones. In addition, it activates the work of the central nervous system. Naturally, in this state, you will not immediately fall asleep. Therefore, you should not exercise before bed.
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I exercise in the morning: it invigorates me. In addition, the body is restored during the day. If you train at night, then you will recover in a dream and wake up dead. If you wake up, and yesterday the training was in the morning, then you feel much better. And you need less time to sleep.
Cold shower
Cold showers produce a hormonal response similar to exercise. For the body, cold is a stress in which you need to survive. He can't sleep again. If you want to cheer up - douse yourself with cold water. nine0003
But don't take a cold shower after a workout: your immune system is temporarily lowered. You can get sick very easily, and a second dose of stress will help.
Bedroom
The bedroom should be cold, dark and fresh. During sleep, body temperature drops slightly. It is logical that it should not be increased at night. And given how badly batteries work in the post-Soviet space in winter, you always have to sleep with the window open.
The window in my bedroom is always open. The reason is carbon dioxide, which accumulates in the room. After two hours in a room without ventilation, carbon dioxide becomes so much that it becomes stuffy. This is called carbon dioxide poisoning. Sleeping in such conditions is much more difficult. nine0003
Sleep in the dark. To do this, I completely curtain the windows in autumn, winter and spring. In the summer, I sacrifice darkness in favor of nature's best wake-up call: the sun shining on your face at five in the morning. Summer is the best time to get up not under the nasty melody from the iPhone, but under the rays of the sun.
Alarm clock
Our sleep consists of cycles: several phases replace each other in turn. The only thing we need to know from this is that REM sleep is the easiest time to wake up. In it, the body practically does not sleep, but is in a state of dormancy. In this phase, you toss and turn the most. nine0003
I use the Sleep Cycle app to determine REM sleep.
I set a 30-minute wake-up time (say, 6:00 am to 6:30 am). My phone lies next to my pillow all night. The microphone picks up all sounds. When it's time to wake up, he waits until I start tossing and turning. For him, this will be a sign of REM sleep. At this moment, he will wake me up.
Screenshot from Sleep Cycle
Feelings indescribable. Waking up in REM sleep is much easier. nine0003
In winter, when daylight hours are late, I use an artificial sun. My alarm clock half an hour before getting up, the warm light in the room starts to turn on smoothly. By the time of awakening, this sun is already shining in full and the birds begin to sing.
Instead of the sun
Smartphone and computer screen
30 minutes before bedtime, I try not to use my computer or smartphone. Their screens emit blue light. And it reduces the production of melatonin, a hormone that is released in the dark and helps to fall asleep.
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I have f.lux on my computer, which makes the color of the monitor warmer in the evening. The tablet automatically turns on the Night Shift mode, which does about the same thing.
Screenshot of f.lux
I start my morning from the smartphone screen. I go to Instagram. The light entering the eyes after waking up is a good alarm clock. And a dose of dopamine helps to get rid of the typical "well, another ten minutes."
Walking before going to bed has had a very positive effect on me. Often my wife and I spend 30-60 minutes on this. The benefit is huge.
After such a walk, falling asleep is much easier, and sleep is of better quality.
nine0003
Daytime sleep
Often at lunchtime there is a decline in strength, energy and mood. The body increases the blood supply to the digestive organs. Therefore, the blood supply to the brain is slightly reduced - because of this, you tend to sleep.
From an evolutionary point of view, you must be active until you catch a mammoth and eat it. This will ensure your survival. At the same time, after eating, you don’t need strength, it’s time to turn on the energy-saving mode.
There are two ways to deal with this. The first is to reduce your lunch. But life didn’t prepare us for this, right? The second is to sleep for 20-30 minutes after dinner (this is what is called nap in English). nine0003
I often sleep during the day at work. In any case, I try. If it works out - cheers, I got two working days in one day. If not, I'll be tired for the rest of the day.
I have worked out certain rules for daytime sleep for myself:
You can negotiate with any adequate boss, explain how this positively affects health. And any inadequate can be replaced. What methods do not work
I have shared with you methods that work for me. But there is one thing that didn't work for me. A negative experience is also an experience. nine0003
As I wrote at the beginning, I absolutely cannot get up, much less fall asleep at the same time.
However, I managed to reduce the variation in the rise time, which is already progress.
Morning rituals from productivity books don't work for me. Meditation, jogging, "eating a frog" - no, I'm sorry, but I will not do this. It doesn't give me pleasure.
So, when I will give it up is a matter of time. It gives me pleasure to wake up and go to Instagram for ten minutes - so be it. nine0003
We are human beings and our circumstances can be different every day. Sometimes we are full of energy, sometimes we wake up with the desire to destroy humanity. What the hell is meditation here, I want to sleep.
If the question: "Do you get enough sleep?" If you answer: “Where?”, then here are some tips on how to organize a good night's rest and make up for chronic sleep deprivation. Agree, it is impossible to effectively cope with work when the strength is at the limit and there is only one thought: to sleep.
The good news is that you can learn how to get enough sleep and overcome fatigue! We tell you how. nine0161
If someone suddenly forgot, let us remind you: healthy sleep is the key to the successful functioning of the whole organism, including the fruitful work of the brain. A few good habits will add vigor and improve well-being. Isn't this what teachers, parents, and schoolchildren need so much? And to everyone who lives in this world.
Organize the right place to sleep
The bedroom is the basis of rest, so it should be free from everything that can interfere with a restful and healthy sleep. Maintain order and get rid of unnecessary things and garbage. nine0003
Monitor temperature. Ideal for the bedroom - 18-22 degrees Celsius.
Get as dark as possible. Turn off all electronic devices before going to bed. You can use special sleep masks, for greater effect, you can put a couple of drops of lavender essential oil on your wrists, pillowcase or pajamas.
Don't skimp on a comfortable bed and mattress. Buy bedding made from lightweight, breathable fabrics and wash it at least every two weeks.
Don't skimp on sleep
The best way to prevent excessive fatigue and lack of sleep is to get seven to nine hours of sleep a day. We already foresee sad comments: “But notebooks won’t check themselves!”. They will not check, you are right, but your health is the most important thing that you have, and at the same time your loved ones and, by the way, students.
Keep in mind that it takes between ten and thirty minutes for a person to fall asleep, so set aside at least eight hours of your time for proper rest. nine0003
Review your diet
Include foods rich in minerals and vitamins in your diet: carrots, mushrooms, tomatoes, seafood. Some foods will need to be reduced, especially a few hours before bedtime: avoid high-fat foods, avoid coffee and alcoholic beverages.
A balanced diet with enough protein and complex carbohydrates will not only improve sleep, but also give energy to the body throughout the day.
And remember about water - you need to drink at least two liters a day! nine0003
Learn to fall asleep faster
Count how many hours of precious sleep you lose while lying in bed with a smartphone in your hands. Here are some tips to help you fall asleep faster:
This will make it easier to prepare the body for sleep, and will also help to maintain sleep and wakefulness.
Think about what brings you pleasure, makes you calm and relaxed? A warm bath, a good book, art, yoga, meditation will all lift your spirits and make you feel better. Introduce such leisure into your evening, create your own ritual, and this will help you go to bed in a more calm and relaxed state.
Don't sleep too much
We all understand that lack of sleep leads to fatigue and irritability. But did you know that sleep can be too much?
An adult needs seven to nine hours of sleep, and if you sleep more than nine hours, this may indicate some health problems.
Too much sleep increases the risk of diabetes, obesity, headaches and even depression.
To understand how much time you need to sleep, try organizing yourself a “sleep vacation” (remote work, which some organizations are now switching to, helps us): go to bed at the same time, but get up on your own without an alarm clock. nine0003
After a couple of days, the regime will normalize, and you will be able to understand how much sleep you need in order to feel better.
Sleep during the day
If you are tired, there is nothing wrong with taking a nap during the day. Taking a nap at lunchtime will save you evening hours that you can devote to your hobby.
