After a nightcap, you called it a day. You tucked yourself in the blanket, lied down on your cushy body pillow, turned the lights off, and took your phone to set an alarm for the next day’s work or perhaps leave it without the snooze buttons because you don’t mind sleeping late in the morning. That’s it. You can luxuriate in a good night sleep and the cycle goes on and on.
Perhaps you have gone through the same routine each night before you prep for bed. Then, the next day you wake up feeling normal, revitalized, and ready to accomplish another pile of work for the whole day. Unbeknownst to many, certain processes take place in our bodies every time we sleep and though we think our bodies and brains shut down and go offline, they do not.
Your head’s probably brimming with diverse thoughts and wondering what actually happens in your body when you are sleeping. It seems unfathomable but the scientific world unravels some of the interesting details that might conclude this phenomenal mystery.
The Stage of Sleep
As every fascinating occurrence and function inside our body come up in a particular phase of sleep, determining these stages truly is significant. Every stage somehow defines the inexplicable events that we encounter and the body reactions and movements that we act out while we are sleeping.
You probably have felt like you haven’t slept at all. This first stage of sleep is not where you get into the deepest phase where vivid dreams and nightmares pop out. Like if you lie down for a bit and the TV or radio turns on with the piercing sounds, you can easily wake up. Sometimes, even the slightest scratch might wake you.
In this phase, as your muscles relax and head your way to sleeping, you might also experience twitching known as hypnic jerks. No, you are not possessed by a troubled spirit or something. These hypnic jerks do come every now and then while you are sleeping but do know that these are perfectly normal. These occurrences might be triggered by loud noises, bright lights, a sensation of falling, and hallucinations.
The assistant professor of psychiatry at the University of Pennsylvania, Philip Gehrman, called this stage as the average sleep. As the term itself explains, you don’t go to the phase where you indulge in a deep sleep though this takes an immense part of your night, approximately half of it. The National Sleep Foundation states that, in this stage, your temperature drops and your heart rate slows down and functions properly. So does your blood pressure.
A lot of events occur in this stage of sleep and finally, where you get the deepest sleep for the night. Your body and brain function to repair tissue and reinvigorate the energy you’ve lost after an exhausting day. Also known as the restorative stage, growth hormones are released which are responsible for building muscles and further development in your body.
If ever you’ve heard your mom, dad, or sister telling you that you had ever been talking, walking, or even eating while asleep, you were probably in the third phase of sleep. And since you are getting the deepest sleep at this phase, it may also be difficult for someone to wake you up.
Rapid Eye Movement or REM Sleep
Where do those unexplainable, vivid, and sometimes strange dreams occur? Though you do experience dreams in all other stages of sleep, the ones that leave realistic fragments of stories in your head, happen during REM sleep. REM sleep or Rapid Eye Movement evidently imply the movement of your eyes that move rapidly back and forth while in this phase of sleep. As you go through REM sleep, your brain functions almost the same as it does when you are awake which explains why you sometimes feel like you were actually there in your dream.
Sleep paralysis also takes place during REM sleep. This is when the person goes through the stage of wakefulness and sleep which result in the inability to move but still conscious. It seems so real as if the things that the person may hear, see, or feel are present. Episodes of sleep paralysis are usually triggered by stress, depression, anxiety, sleep deprivation, and abnormal sleep cycles.
What Your Body Really Does When You are Asleep
As what has been discussed, your body goes through different stages of sleep and does a lot of things that you are unaware of. Here are some of the things that your body does when you are asleep:
1. Your brain works overtime.
Your brain functions like a hardworking employee and works overtime to accomplish a ton of tasks and duties. Just as when you are sleeping, your brain doesn’t go offline but rather open up departments in your brain that gather and consolidate memories whether they are old and new.
Because your brain is as active as when you are awake, it incredibly processes information and experiences that we have acquired all throughout the day to help you make practical decisions when you awake. Your brain also conducts a general cleaning while you are sleeping. It enables your body to flush out the toxins and leave only the essentials.
2. Your body temperature drops.
Have you ever experienced waking up all wet and sweaty? Well, that’s because the body temperature drops when you are sleeping although it starts to rise again when you’re about to wake up in the morning. Sigrid C. Veasey, a neuroscientist and professor of medicine at the University of Pennsylvania for Sleep and Circadian Neurobiology, stated that the body’s capacity for thermoregulation loses and why it happens is still unexplainable.
3. Irregular and regular heart rate and breathing.
The heart rate and breathing vary every time you are sleeping. During the first stage of sleeping, the heart rate and breathing become irregular. But as you go through the second stage, they slow down and regulate as well as the other parts of your body. According to Sigrid Veasey, “the intestines quiet down in the nighttime, and the liver goes from trying to detoxify during wakefulness to trying to build and synthesize when you’re sleeping.”
4. Your muscles become paralyzed.
This usually happens during REM sleep. As what was mentioned, vivid dreams take place at this phase of sleep and as you unravel those scenes and fragments of stories in your head, your muscles become paralyzed to control your body so you’ll refrain from acting out your dreams. This is obviously temporary so you won’t have to worry.
5. The tissue repairs and grows.
Growth hormones are released when you are sleeping. As you go through the third stage of sleep or the deepest sleep of the night, your body releases growth hormones to work on your body’s development. Muscle cells start to build, healing incessantly process, and the other parts of your body keep on developing.
6. Your muscles relax.
As your body enters the second stage of sleep, your organs and other parts of the body all chill out and so do your muscles. When you lie down on your cozy memory foam mattress topper at night for a sleep, your muscles just keep all calm and relax in order to give you the rest you need after a long tiring day. No wonder you feel rejuvenated with much lesser pain when you wake up in the morning.
7. Your blood pressure drops.
One of the ways to avert the risk of high blood pressure is a good night sleep. Not only is it a way to give yourself the much-needed rest but because as soon as you’ve fallen asleep, your blood pressure drops. It is commonly known as dipping or nocturnal dipping which is also probably related to cardiovascular function.
8. Your body releases appetite hormones.
Did you ever find yourself in the middle of the night rushing to your fridge craving for food? As you get into a deep sleep, your body releases ghrelin or hunger hormones and leptin, hormones that control the appetite. When your body receives a full night sleep, it helps regulate the appetite hormones. So if you lack sleep or you stay up too late, your body will not be able to regulate the hormones properly leaving you hungry and craving for something to eat. Much worse, it will result in weight gain.
9. You may experience parasomnia.
One of the strange but fascinating things that occur while you are sleeping is parasomnia. It includes abnormal movements, unusual behaviors, emotions, and reactions where a person tends to sleep, walk, talk, or even eat while sleeping. Some experience even much stranger than these. This usually occurs in deep sleep or the third stage of sleep. According to the National Sleep Foundation, parasomnia is due to the side effects of medications and lack of sleep.
It seems that every aspect is a complex matter and beyond our knowledge, but learning more about what happens to our bodies while we are sleeping is surprisingly enthralling. Though the scientific world has laid out researches and studies about our bodies’ activities while sleeping, there is still much more to know, learn, and understand. Inevitably, what really happens in our bodies when we aren’t awake truly is still a mystery.
The studies and researches mentioned above may be true to you or to some people. But the results still vary from one person to another depending on the age, sleep routine, health condition, and many other factors. If the pattern of your sleep or the activities your body does when you are sleeping seem unusual, don’t hesitate to consult your doctor for professional advice.