Sleep and Success; two words we don’t often see put together yet they essentially complete one another. Sleep promotes memory and cognition, boosts our immune system, improves our physical and mental health, helps us feel more energized, and above all helps us prosper throughout the upcoming day.
In our busy, fast-paced era, sleep tends to be overlooked in relation to all our other responsibilities. Exams coming up? Let’s pull some all-nighters to cram. A big project around the corner? Let’s work non-stop for the next few days. Howbeit, we don’t see how these actions could be detrimental to our performance and overall well-being.
What is sleep?
Sleep is a physiologic state of reduced consciousness, voluntary body movement, and electromyographic activity. It is distinguished from wakefulness and disorders of unconsciousness by reduced responsiveness to external stimuli. Usually, we know a person is asleep by the closure of their eyes, reduced breathing rates, and a somewhat constant or altered body position.
Several neurotransmitters and some hormones such as melatonin function in the hypothalamus to control sleep. The sleep induction zone is located in the anterior hypothalamus and the wake-promoting region is located in the posterior hypothalamus.
Sleep is divided into two types of sleep that are divided into 4 stages. The two types of sleep are non-rapid eye movement sleep (NREMI) and rapid eye movement sleep (REMI). The table below summarizes the key differences and similarities between the two.
Differences and Similarities between non-rapid eye movement sleep and rapid eye movement sleep.
The stages of sleep can be summarized into light and deep sleep. The first two stages are NREM Stage 1 and 2 which involve light sleep, and the later two are NREM Stage 3 and REM sleep which involve deep sleep. Each sleep cycle goes through these four stages and is equal to 90 minutes each. The number of complete sleep cycles is what determines the overall feeling of restfulness when you wake up.
How much sleep is enough?
Everyone requires a different amount of sleep according to their daily energy needs. However, on average, a young-adult optimally requires anywhere from 7 to 9 hours of sleep a day. Take a look at the graph below from the National Sleep Foundation, where they outline the average for each age group.
Sleep Duration Recommendations according to age group
As important as the amount of sleep you get is, the type of sleep you get is much more important. Short sleep that is sound is much more fruitful than longer hours of interrupted sleep. Some highly successful figures have admitted to sleeping somewhere between 5 to 6 hours a night. However, we should assume that these few hours are definitely filled with some intense uninterrupted sleep. Let’s take Elon Musk for example: he stated in an interview that he sleeps about 6 hours a night from 1 am to 7 am. Let’s not confuse this with the ‘Da Vinci Sleep Schedule’ which involves a polyphasic sleep schedule divided throughout his day, totaling to about 5 hours of sleep per 24 hours. That definitely doesn’t sound like everyone’s cup of tea.
Don’t take this to mean that less sleep = more genius powers. That’s far from the point I’m trying to make. Einstein slept 10 hours punctually each night. What you need is to find your sleep sweet spot, whether that be 6 hours like Elon Musk or 10 hours like Einstein.
Although the amount of sleep is important, the quality of sleep is also as important. Good quality sleep is essential to feel rejuvenated the next day. To improve the quality of sleep you should engage in beneficial sleep habits: These include going to bed at a consistent time each day, making sure your environment is conducive to sleep avoiding electronic devices for at least an hour before sleep, and many other sleep habits. For further reading on sleep habits, you can click here to read the CDC guidelines.
But why sleep?
Sleep is crucial for our day-to-day functioning. It allows our bodies to rejuvenate and our minds to reset and prepare for the challenges the next day holds. Overall, sleep plays an important role in behavioral and physiological functions.
Therefore, let’s discuss sleep in each one of these categories :
- Sleep and Energy
- Sleep and Mood
- Sleep and Memory
- Sleep and Performance
- Sleep and Health
Sleep and Energy
Waking up after a good sleep and stretching is one of the best feelings: Feeling every single one of your muscles being pulled taut and released, you get out of bed and your day begins, fueled with energy pumping through your veins, ready to tackle ANYTHING.
Yes, sleep does that. Sleep allows your brain and body to take a well-deserved break to simply reboot. Your body refreshes many systems during those few hours, including hormonal systems, temperature regulating systems, and appetite systems.
Ghrelin and Leptin are two hormones that have been shown to have major effects on energy balance. A study conducted by Spiegel et al showed altered leptin and ghrelin levels after short-term sleep restriction. “They found that average leptin levels measured after 2 nights of 4 h bedtimes were 18% lower and ghrelin 28% higher than after 2 nights of 10 h bedtimes.”
Throw away those energy drinks and hit the sheets!
Sleep and Mood
Depression has been linked to sleep in many ways. Firstly, poor sleep is linked to depression. As many as 90% of depressed individuals complained of trouble falling asleep or staying asleep. Many tend to wake up in the early hours of the day unable to fall back asleep after just a few hours of sleep. Furthermore, those suffering from sleeping disorders such as insomnia and narcolepsy, among others, tend to be depressed.
People who sleep less have a decreased ability to recognize anger and happiness. Therefore, sleep deprivation reduces your ability to interact socially. Simply speaking, when we don’t get enough sleep we tend to be much more irritable and in a bad mood. Take for example, how you felt after only getting two hours of sleep within 24 hours, your tiredness didn’t just make you moody, it made you mentally exhausted, angry, short-tempered, and many more stress-inducing emotions flooded your system. It’s easy to see that getting adequate sleep is necessary to elevate mood and feelings.
Sleep and Memory
As we mentioned before, students tend to pull all-nighters before an important exam or assignment is due, forsaking precious hours of shut-eye. Little do they know that taking as little as a nap can boost their memory exponentially for that exam.
A few hours of sleep can help clear out irrelevant information and solidify relevant information. During NREM sleep, the brain filters the information you learned that day, brooming away all the irrelevant things that happened and sundering them from the important memories.
Not only is sleep important in increasing concentration and focus, which are both essential in learning efficiently, sleep also plays an important role in memory consolidation, which occurs mainly during the sleep cycle we spoke of previously. All that effort put into grilling information into your frontal lobe must be consolidated with a good night’s sleep. Pulling an all-nighter sounds kind of counterproductive now, doesn’t it?
During my time in university, I made sure to get at least one or two sleep cycles in before my exam the next day. Knowing that those few hours of sleep would have let my neurons get to work and construct those nice little neuronal connections that enhance memory.
Sleep and Performance
The four stages of a sleep cycle are what prepare your brain for learning and performing at your ultimate potential. Poor sleep is linked with the inability to stay focused, taking longer to complete tasks and reduced creative potential. In other words, good sleep can improve concentration and productivity.
Not only can sleep increase productivity, but it can also increase athletic performance! Sleep quality in athletes is “associated with improved performance and competitive success”, according to a study conducted by Andrew M Watson on Sleep and Athletic Performance. This is directly owing to the fact that sleep has an unequivocal positive effect on accuracy and reaction time.
Decreased sleep is also associated with diminished motivational drive and a higher risk of getting burnout. To read more on burnout, check out my previous blog dedicated to that very topic.
Sleep and Health
Sleep plays an important role in keeping us in good health throughout all the stages of our life. Yes, less sleep may cause temporary grogginess and fatigue the next day, but there are some long-term effects associated with poor sleep. Sleep can affect the body in the following ways:
- A weaker immune system : Poor sleep has been associated with a weaker immune system, predisposing to more infections and bodily fatigue, such as the common cold. It is also linked to increased inflammation in the body.
- Weight changes and Energy levels : Staying up late and not getting enough sleep has been linked to overall weight gain and decreased energy levels which are required for performance. This can be attributed to the fact that people who stay up late tend to consume more calories than those who sleep earlier. Remember that sudden late night craving for some pizza? Or was it some fries? Ice cream?
- Chronic Illnesses : Poor sleep has also been linked to a greater risk of heart disease, stroke, and an increased risk of developing type 2 diabetes.
Sleep has also been linked to many other bodily dysfunctions, however that’s a conversation for another time. The point is, polishing up our sleep quality is beneficial in improving any health condition and preventing them in the first place.
All in all, sleep is exquisite, beautiful, stunning, and magnificent. Not only does it provide the ultimate form of rest and relaxation, it gives us everything we discussed in this blog. A boost of energy, improved mood, stellar memory and memory retrieval, enhanced performance, and last but not least, a tip-top immune system and overall health.
“A good laugh and a long sleep are the two best cures for anything.”-Irish Proverb
And now, good night!