The Science of Sleep: How to Sleep Well
The argument about the quantity and quality of sleep for adults is never-ending. Should you go to bed before dark? Does a mid-day nap has a positive or negative effect on your personal effectiveness? Why you can feel tired even after eight-hour sleep? Let’s dig into the question of what is quality sleep and how to get it.
REM vs. Non-REM sleep: Why Sleep Stages Are Important
A grown-up adult needs from 7 to 9 hours of sleep per day. There are two main types of sleep: Rapid Eye Movement, aka REM sleep and Non-Rapid Eye Movement sleep or NREM. It is crucial that you have enough of both for a full recovery. The NREM sleep takes 75-80% of all sleep time, and this period is the most useful for the human body. During this time, the muscles get blood flow, the tissues regenerate, and useful hormones (for example, testosterone) replenish. The brain lymphatic system flushes out beta-amyloid metabolites, which accumulate in case of deficiency in NREM sleep and can lead to dementia or Alzheimer’s disease. During this stage of sleep, our brain sorts our memories and transfers then from short-term into long-term memory.
In the second stage, the brain generates dreams. While we watch the dreams, the brain structures our emotional memories and helps to memorize various skills from switching on the coffee machine to driving a car.
What Keeps Us from Having a Good Sleep
Apnea or stopping breathing while asleep can break the deep sleep and all important recovery processes related to it. The recurrent waking up and falling asleep during the night, caused by apnea, break the structure of sleep, which makes us feel tired even after sleeping full 7-8 hours.
Temporary deprivation can be another cause for breaking deep sleep, for example, if during several weeks you slept less than usual. In the short run, it can lead to decreased performance, cause mid-day slumps, irritability, and anxiety. In the long term, it can lead to not only psychological but also physical problems: obesity, development of type 2 diabetes, hypertension, and cardiovascular diseases.
Your sleep can be influenced even by temperature in your bedroom, which is often overlooked. The lower is the temperature around us, the easier it is to fall asleep and to shift from light sleep to deep sleep stage. The sleep psychologists consider 16-18 degrees Centigrade as an optimal temperature for sleep.
What is Good Sleep Hygiene Practices
The problems with sleep don’t pop up from nowhere, and it’s advisable to take preventive measures to avoid them.
– Make a schedule and go to bed at the same time. It is boring, but it can help to avoid situations when you went to bed two hours earlier but couldn’t fall asleep.
– Don’t drink alcohol 4 hours and coffee 6 hours before sleep. Besides, tea and chocolate include caffeine, so you should be careful with them as well.
– If you feel tired or can’t sleep enough at night, have a mid-day nap. But take it for no longer than 20-40 minutes. Waking up after a short sleep will be easy, and you will be more productive and alert, as proven by the research of NASA pilots and astronauts.
– Keep a sleep diary — it will help you to understand which habits prevent you from falling asleep. This diary can also be of help to a sleep disorder consultant to research the problem, if necessary.
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