Why is sleep important?

Why I feel sleepy?

Sleep is a vital part of every person’s overall health and well-being.

Your body has an inner clock determined by your circadian rhythm.
The 2017 Nobel Prize for Physiology and Medicine went to a Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for their research into “how plants, animals and humans adapt their biological rhythm so that it is synchronized with the Earth’s revolutions.” This group of scientists has helped us understand the workings of the body’s internal clock, a 24-hour cycle of bodily changes called the circadian rhythm. Our circadian rhythms are set by internal and external factors.

Internal factors

Your body has a natural cycle of sleep and wakefulness. This cycle is primarily regulated by a nerve cluster in the hypothalamus called the suprachiasmatic nuclei, which sends signals to other parts of the hypothalamus and the pineal gland.
These signals regulate a daily cycle of changes in:

  • Body temperature
  • Hormone levels (including melatonin, which is released during the night and correlates with sleepiness)
  • Metabolism

External factors

The circadian rhythm responds to an organism’s environment. External factors affecting these rhythms include:

  • Light exposure
    Exposure to daylight signals your body to activate molecular processes that make you more wakeful. Once the sun sets, your pineal gland produces the sleep-promoting hormone melatonin, which stays at a high level all night and dissipates in the morning.
  • Temperature
  • Eating and drinking patterns

Typically, these changes make a person:

  • Feel wakeful in the morning.
    As a result, people tend to find it easier to concentrate on work during the morning or in the late afternoon/evening.
  • Experience a significant dip in energy around mid-afternoon.
    The timing of the mid-afternoon dip can vary, but most people experience it between 2 and 3pm. This is generally a good time for taking a break or even a nap.
  • Become sleepy at night.

So your body is biologically adapted to sleeping at night. This is one reason why you don’t want to maintain an overly late sleep schedule. 

Melatonin levels generally rise around 9pm and remain elevated for roughly 12 hours. 

This period is the best time for restful sleep. If you go to bed very late and wake up well after sunrise, you sleep schedule won’t match the period when your melatonin levels are the highest, and it will be less likely you will get a good night’s rest.

It also means that you should avoid bright lights right before bed and sleep in total darkness. Darkness is how your body knows when to produce melatonin. By keeping your sleep environment dark, you optimize your ability to fall and stay asleep.

In short is the combination of your inner rhythm and surrounding environment that determine the optimal sleep schedule for you.

Why do I need a consistent sleep schedule?

You need one to stay healthy and productive.
Getting a good night’s sleep is one of the most important aspects of a healthy and productive life. As such a vital part of your wellbeing, sleep should to be scheduled just like your meals or work time. By keeping a consistent sleep schedule, you can improve your quality of rest and thereby raise your efficiency throughout the day.

An irregular sleep schedule can be as bad as not getting enough sleep. It can lead to:

  •  A worse night’s sleep.
    Researchers analyzed the sleep patterns of 160 Taiwanese students and found that irregular sleep patterns correlated with shorter sleep times. What’s more, even after adjusting for quantity of sleep per night, students with irregular sleep times showed more cognitive impairment the next day.
  • Metabolic disruption.
    ​​​​​​A study among middle-aged women found that an irregular sleep schedule correlated with a greater Body Mass Index and higher diabetes risk.

Not only does it upset your health, but an irregular sleep schedule will hurt your performance and productivity during the day.
Disturbances to one’s sleep schedule are associated with:

  • Worsened attention.
    A Baylor University study focused on interior designers who alternated late work nights with “catch-up days” when they would get more rest. They found that an inconsistent schedule made participants less able to maintain attention.
  • Lower creativity.
    The same study found that irregular sleep patterns made participants less creative.
  • Worse cognitive performance.
    A study among Harvard undergraduates found that students with irregular sleep schedules had lower academic performance, irrespective of sleep duration.

In short, regularly staying up late to do extra work won’t make you more productive, but it will harm your health.

Check out this video to learn more about how lack of sleep impairs productivity.

Should everyone have the same sleep schedule? Am I a night owl or a morning person?

There really are!
Circadian rhythms follow a similar pattern among humans, and they generally follow the natural cycle of daylight. But the precise timing of these cycles can vary across a wide spectrum, based on biological predisposition. At one end are people who wake up early without needing an alarm: “early risers” or “morning larks” in sleep research. At the other end, we have people who feel most energetic at night: “night owls.”

“Chronotype” is the word scientists use to describe where someone falls on this scale. At one end, a morning larks may wake up without difficulty at 6 am, feel most alert around noon, and go to bed at 10pm. At the opposite end, a typical night owl might struggle to get out of bed in the morning, feel most alert in the late evening, and go to bed well after midnight.

These chronotypes aren’t just a matter of personal preference. Indeed, they appear to be hard-wired into our brains.

In one study, researchers identified a genetic variation that may be responsible for up to a one-hour difference in the time people tend to fall asleep. Examining the genotypes of a 1,200-person sample, the researchers found a single variation near the PER1 gene that accounted for this difference in participants’ wake-sleep schedules. These cycles also affect the structure of the brain.

In another study, “night owls” showed increases in melatonin levels 2-3 hours later than “morning larks.”

Yet another study found evidence that brains of different chronotypes show actual physical differences. Specifically, the brains of “night owl”-type subjects showed a diminished integrity of white matter in certain areas of the brain, perhaps as a result of chronically needing to wake up early. By understanding your own biological rhythm, you can plan your schedule around your body’s natural cycle of sleep and wakefulness.

So how can you determine your chronotype?

You can get a rough sense by looking at the times when you tend to wake up and go to sleep on days when you don’t have work or other obligations that interfere with your nocturnal schedule. This most likely reflects your natural cycle. Test yourself in the “10-day sleep challenge” program in our app and find out if you’re a night owl or a morning lark.

Can you quickly review the main points we covered?

Of course! Based on scientific studies of circadian rhythm and chronotypes, you should set a nightly sleep schedule that fits the following requirements:

  • Consistency
    Go to bed and wake up at the same time everyday. Make sure your weekend schedule doesn’t vary from your weekday schedule by more than one hour.
  • Matches your chronotype
    Determine your chronotype using the program “10-day sleep challenge” in your Welltory app and fit your work hours to your chronotype as closely as possible.
  • Follows the cycle of natural light
    Because the sun influences your circadian rhythm, you want to have your sleeping hours coincide with night time – i.e., when your melatonin level is highest. Generally, this means that you want to set your bedtime earlier than midnight. You should also lower the lights as you’re preparing for bed and make sure the rooms entirely dark when you go to sleep.

Once you have set a new schedule for yourself, you will want to adjust to it gradually. If you are making a large shift, you should pick some smaller increments along the way.

For instance, let’s say you want to go to bed one hour earlier each night. Don’t try to go to bed an hour earlier immediately. Instead, turn in 15 minutes earlier for a few days. Then, go to bed another 15 minutes earlier for a few more days. And so forth. By moving in these smaller increments, you make your new goal much more attainable.

How sleep schedule doesn’t coincide with my body’s internal rhythm?

Yes. Many sleep problems are actually circadian rhythm disorders. Both the natural cycle of daylight and one’s personal chronotype set a certain pattern for the body’s circadian rhythm. These disorders occur when social and professional pressures prevent a person from maintaining a consistent schedule according to this pattern.

The costs of living out-of-sync with your body clock are serious. According to one very large study, social jet lag is associated with a higher risk of obesity among 65,000 surveyed participants. Another study found that even a small amount of social jet lag could cause a substantial blow to overall health, especially making heart disease more likely. What’s more, these researchers found that “these effects were independent of age, socioeconomic status, how much sleep people got and insomnia symptoms.”

The effects are especially hard on night owls. Research suggests that they are at increased risk for depression, daytime fatigue, and nicotine and alcohol addiction. It is hypothesized that these negative effects result from the disconnect between their natural rhythms and typical work schedules. For this same reason, night owls have a tendency to be less punctual and have more difficulty controlling their emotions.

The best way to fight social jet lag is to keep a stable sleep schedule. Be sure not to sleep in on your days off – at least not by more than one hour.

Work is crazy. What if I can’t keep a regular sleep schedule?

That’s okay. You can at least lessen the effects of having an irregular sleep schedule. For instance, napping has been shown to counteract the effects of sleep deprivation.

One study found that a 60- to 90- minute nap was as effective as a good night’s sleep for improving performance in a perceptual learning task. Another study found that naps made subjects more patient and better able deal with frustration. In other words, a nap can counteract both the cognitive and emotional drain of an irregular sleep schedule.

The ideal time for napping for most people is in the mid-afternoon (between 2 and 3pm), since this is when we have a natural dip in our energy. The ideal length of a nap depends on how tired you are.
The APA suggests two options:

  • A 20-minute refresher
    This will give you a substantial pick-me-up without further messing up your regular sleep cycle.
  • A 90-minute long nap
    This is the ideal length if you have a lot to accomplish in the evening and are struggling to keep going. In 90 minutes, you can complete one full sleep cycle, which will refresh your energy. But remember: long naps can make it harder to get to sleep at night and further throw off your routine. So only do this when necessary.

There are a couple other ways to make yourself feel more energetic during the day:

  • Simply moving around more 
    It can help you regain focus as your energy wanes.
  • Open the curtains or go outside  
    Sunlight can make you feel more energetic.

More generally, healthy everyday habits — eating well, exercising, staying hydrated — will help your body cope with effects of an irregular sleep schedule.

What if I travel a lot by plane? How can I keep up my routine?

We’ve already touched on jet lag in our discussion of circadian rhythm. Flying across time zones is a quick way to get your schedule out of sync with your body clock. Both the number of time zones you cross and the direction of travel will affect how long it takes your body to adjust to being on a new schedule.

While there is no perfect solution to jet lag, there are a few things you can do to reduce its impact:

  • Melatonin
    This hormone regulates your sleep cycle, and there’s some evidence that taking melatonin at night may help you get back on a normal schedule. You should talk to your doctor, however, if you have epilepsy or take blood thinners.
  • Light exposure
    Several sleep researchers believe that you reduce jet lag by “phase shifting,” that is, controlling your exposure to light and dark before a trip to adjust your body’s circadian rhythms in the direction of your destination time zone. You can use this free online calculator to figure out what hours of light exposure will best prepare you for an upcoming trip.
  • Time your flights
    If you are flying west, choose a flight that leaves in the first half of the day and arrives in the evening. If you are flying east, pick a night flight.
  • Adjust your schedule before leaving
    If you are flying from east to west, you can start going to bed a little earlier several nights before leaving. This will shift your nightly routine in the direction of your destination time and make for a milder adjustment when you arrive. Of course, if you’re flying in the opposite direction, you will want to move your bedtime a little later.
  • Adjust your sleep times upon arriving
    If you’re flying west, don’t sleep until you arrive and go to bed on schedule at your destination time. Don’t get up later than 7am the next morning. If you’re flying east, be sure to sleep on the flight.
  • Caffeine
    couple studies have found slow-release caffeine can help readjust your hormonal rhythms after they have been disturbed by jet lag.
  • Keep hydrated
    Besides the time difference, air traveler often leads to dehydration, which can affect your ability to sleep. Drink plenty of water during your flight. Minimize caffeine and alcohol consumption on your travel day, as both contribute to dehydration.
  • Stay active during layovers
    Get yourself up and moving in the airport. During a very long layover, try to spend half an hour to an hour outside the airport.

Although you might find several other remedies online, most of them are not borne out by scientific research. For instance, according to the CDC, changes to diet and physical activity don’t really help much with jet lag, nor do hypnotic medications.

Overall, the most effective techniques are those that adjust your circadian rhythm to the new time zone.

And what if I’m lying awake in the middle of the night?

Okay, let’s imagine you’re in that situation right now. It’s the middle of the night and for whatever reason you can’t sleep. There are also some things you can do right now to improve your chances of getting to sleep tonight:

  • Take control of your thoughts
    Anxiety is one of the most common reasons why people lie awake at night. Meditation and positive thinking techniques can help you get control of your feelings.
  • Get out of bed
    Experts agree that you shouldn’t lie awake in bed more than 20 minutes. Nothing is worse for insomnia than lying in bed thinking about falling asleep. Get up and try some relaxation techniques, such as meditation, controlled breathing, or progressive muscle relaxation. Return to bed relaxed and try again.
  • Turn your clock around 
    Watching the time will only increase your anxiety.
  • Listen to calming sounds
    You can use an app like Relax Melodies or Sleep sounds.
  • Keep the lights dim
    Bright light will wake you up more.

In the morning, you will want to go over your sleep schedule and evening routine. Maybe it was something simple that kept you up – like an especially stressful day or accidentally ingesting too much caffeine. Or maybe you need to change something in your routine.

How to set a new sleep schedule?

Start with your bedroom. Here’s how you can make it an ideal sleep environment:

  • Limit your bedroom time
    Experts recommend that you should only use your bed for sleep and sex. In other words, don’t work or watch TV in bed. Maintaining a separation between your sleeping and living spaces will reinforce the mental association between lying in bed and sleep.
  • Block out light
    We’ve already touched on the fact that light makes you feel more wakeful. So, the next thing to do is to make sure that your room is nice and dark. If your window lets in sunlight before your designated wake-up time, consider buying blackout curtains. You may also want to try dimming the lights within an hour of going to sleep.
  • Get the right mattress
    If you wake up in the mornings with lower back pain, this might be a sign that you need to switch mattresses. You want to find the firmness level and mattress type that feel best for you. Here’s a WebMD overview of the factors to consider.
  • Keep the bedroom cool
    Experts say that a cool room (about 65 degrees) makes for the best sleep.
  • Choose a relaxing color scheme and use scented items
  • Buy candles with fragrances you find relaxing.

By making your bedroom an ideal sleep environment, you set the foundation for a good night’s sleep.

What to do before in the evening to sleep better?

Absolutely. You can start preparing yourself for bed as soon as you get home in the evening. It takes a while for your mind and body to relax after a stressful day of work. Many people find themselves unable to stop thinking about work, and these racing thoughts often lead to insomnia.

Happily, there are several tried and true ways to calm your nerves after a long stressful day.
Here are some daily habits that can help you:

  • Make a purposeful division between work and home
    Even if you work from home, business psychologist Peter Shallard recommends making transition rituals to mark off your work hours from your family or leisure time. Always do some specific activity — cooking, going for a run, etc. — to mark that the part of the day when you’re not thinking about work has begun. He also recommends not talking about work during the designated relaxation periods.
  • Take an evening stroll
    According to WebMD, you should try to walk 30 minutes a day several times a week for cardio benefits. If possible, go out to a park or forest. Recent research suggests that being in nature can reduce one’s stress levels (123).
  • Get a workout
     Exercise anytime during the day will help you reduce stress and sleep better at night. Working out in the late afternoon or early evening is a great way to mark the division between your “work” and “home” time.
  • Have an evening relaxation ritual
    This could involve meditating, reading, drinking tea, or taking a bath. You can see our previous lecture “How Should I Relax” for more options.

If you make a habit of doing one or two things, you will find it much easier to unwind in the evenings. This will result in a better night’s sleep.

Eating before sleep

Yes, it absolutely matters. In general, the things you consume during the day affect your sleep pattern. Obviously, you don’t want to have coffee or a strong tea right before bed, since caffeine blocks the neurotransmitter adenosine, which makes you tired. You should also be careful consuming it in the later afternoon or evening since caffeine stays in the body for several hours – though its effects will depend on your tolerance.

Some people think that a glass of wine is the best way to unwind and get some sleep. But this is only half true. Alcohol only helps you get to sleep, but not stay asleep. The problem is the so-called “rebound effect.” Although alcohol does make you tired right after being consumed, it will have the reverse effect on your body a few hours later, when the alcohol metabolizes. This will disturb your sleep cycle and make you feel less rested in the morning.

Food too can affect your sleep patterns. Here’s what to avoid before bed:

  • Chocolate: Contains caffeine and theobromine, stimulant that can increase heart rate
  • Acidic foods: Tomatoes, tomato-based products, citrus
  • Aged or fermented foods: smoked fish, cured meat, aged cheese
  • Burgers and bacon: Stratospheric fat produces acid in the stomach and causes heartburn
  • Soda drinks: Caffeine together with sodium benzoate that aggravates the gastrointestinal tract and promotes acid reflux.

And here are some foods that can help you sleep:

  • Milk: Contains amino acid tryptophan, a precursor to the brain chemical serotonin
  • Tart cherries: Cherries are a natural source of melatonin, and tart cherry juice has been found to improve sleep quality.
  • Complex carbs: Shredded wheat, barley, and buckwheat help digestion and produce melatonin
  • Jasmine Rice: Ranks high on the glycemic index
  • Herbal tea: chamomile, mint, ginger, etc. (but not black or green tea because these have caffeine!)
  • Turkey: Low in fat and contains tryptophan and serotonin.
  • Bananas: Contain the natural muscle-relaxants magnesium, potassium, and serotonin that boosts your mood

If you follow these guidelines for your dinner and evening snacks, you will find it much easier to get to sleep at the correct time.

I’m still can’t fall asleep on time

Don’t worry! There are a few other common habits that sometimes get in the way of a good night’s sleep. Here are some additional behaviors that  you want to avoid:

  • Taking long naps
    While short naps won’t interfere with your sleep schedule, a long nap can make it hard to get to sleep later. The Mayo Clinic suggests limiting your naps to 30 minutes or less. They also suggest that the ideal napping time is between 2pm and 3pm – i.e., when most people’s circadian rhythms make them feel sleepy anyway.
  • Using devices at bedtime
    A recent meta-analysis confirms that there is far-reaching evidence that using media devices at bedtime leads to poorer sleep quality. One reason for this is that the light from a screen can interfere with a person’s circadian rhythm. This is especially true of blue light, which suppresses melatonin. You can reduce this effect by downloading an app, such as F.lux, that adjusts the color layout of your screen to reduce blue light.
  • Working out at night
    Overall, exercise helps you sleep, and if late night exercise is your only option, you can keep doing it. That said, exercise raises adrenaline levels, which can make it harder to go to sleep. So if it’s possible, move your workout to earlier in the day.

By following these guidelines, you will put  your mind and body in ideal shape for a good night’s sleep. If you have been following these recommendations and continue to have difficulty sleeping for several weeks, you should visit a medical professional.

How can I feel more wide-awake in the morning?

Once again, your sleep schedule is fundamental here. If you keep a consistent schedule that matches your body’s internal rhythm, you will feel better in the morning.

Be sure not to sleep in on your days off — a misalignment between your workday and weekend schedules will only worsen the effects of social jet lag. You should try to keep your work and weekend schedules within one hour of each other.

There are also a couple external factors that can help:

  • Daylight
    Open the curtains and let the sunlight wake your body up physically. And don’t despair if it’s overcast out: you can buy an artificial daylight lamp to boost your energy!
  • Get moving
    It’s always tempting to lounge around in bed a little longer. But the sooner you get your body up and moving, the quicker your mind and body will wake up.
  • Contrast shower
    This means alternating between hot and icy cold water as you shower. This technique wakes you up by dilating your blood vessels.
  • Motivation
    As soon as you wake up, remind yourself of your goals for the day. What are you looking forward to?
  • Breakfast
    A healthy, delicious breakfast will give you energy for the day ahead. Looking forward to one might also help you find motivation 🙂

Just make these easy adjustments, and your day will be off to a great start!
And don’t forget to measure your energy levels with Welltory every morning! Taking these measurements every day will help you keep an optimal nightly schedule.

How will I know if my schedule is working?

Data! The more sleep data you track, the better you will be able to manage your sleep schedule. Once you’ve made a plan for yourself, you should be sure to mark down the times when you actually do fall asleep and wake up each day to see how well you are following this schedule. The activity of tracking your hours of sleep each night will serve as a reminder you to keep your schedule.

Of course, you can also track your morning energy levels right in Welltory. This will help you gauge how well your sleep routine is working for you. Welltory is also compatible with several apps and fitness trackers that focus on sleep.

The apps Sleep Cycle (IOS) and Sleep As Android (Android) analyze your breathing patterns to assess sleep quality and duration. Sleep As Android has a built-in feature to help you understand your chronotype. The most popular fitness trackers are Fitbit and Jawbone. Other options are BedditAuraSense,  WMe2Mio FuseHealbe GoBe, and Polar .

Track your sleep, use the data to modify your schedule, and get better rest!

Georgiaphilli
11 Sep. 2019
I have ME/CFS and I find pacing really hard. Welltory helps me know my limits and helps prevent over excretion. I listen to the advice it gives me based on my measurements and stay rested when it recommends and go for a couple minutes walk or gentle stretching when it advices me that my body is strong enough and definitely knows my body better than I do. By preventing crash’s I have more energy to play about with and less suffering. When I first started I was always on red and ‘really bad’ results due to over exertion and the damage to my body it causes but with welltory and it’s help with pacing I now am sometimes on ‘ok’ which is a massive improvement for me and It’s only been a month.
Andrea Miklos
10 Jun. 2019
The app makes me focused on the signs my body gives, and translates well what I should do to improve. It's very useful to see how my body reacts to external factors, such as a walk, workout, meditation. It's great that I can also add the blood pressure measurements, and it's comforting to see that the 2 tools measure almost the same heartbeats. It would be even better if I could add a note of each day, not just tags but longer information.