Brain Science: How Sleep Improves Performance

Brain Science: How Sleep Improves Performance

Sleep is often one of the most neglected aspects of our health. You might not even be fully aware of how much sleep you are getting or how effective your sleep is. But how is a lack of quality sleep affecting your performance and happiness? Sleep, more than anything, is an exercise for our brain and helps us be at our best in life’s challenging, Last 8% moments.

Sleep is one of the most mis-judged aspects of our lives. We often see it as an enemy to our tasks or as indulgence. It gets in the way of the things we want to do – stay up, keep reading a book, watch a movie or the next episode of a TV show. All of those things seem more appealing than just going to bed.  Sleep procrastination can show up as a FOMO – fear of missing out on other things. It’s not that we don’t want to sleep, but that we aren’t willing to quit any of the other activities. 

For some people, sleep also doesn’t appear to be a “productive time”.  We aren’t getting things done while we sleep, we aren’t achieving anything, we don’t see it as “helpful” in the pursuit of our goals.

If you aren’t committing to sleep, it’s important to look at it in a different way: not as something we have to do, but we get to do. Sleep is similar to exercise – it improves our health, the quality of our lives and our performance. Interestingly enough, sleep can be viewed as an exercise itself, because while we sleep, our brain is engaged in various activities – even more than when we are awake.

Two of the major brain processes during sleep are memory consolidation and creating critical neural linkages. What we learned during the day gets consolidated into our longer term memory. Different parts of our brain become stronger in their linkages and that wiring has many positive effects.

 

Benefits of sufficient, high quality sleep

Enough sleep quantity and quality turns our brain into a “conditioned athlete”:

  • We are more creative - 3 x more creative in fact, with an increased ability to find novel solutions to the same problem, compared to someone who’ brain is not as highly conditioned.

  • We are less impulsive. When our brain is highly conditioned, we are less likely to react and more likely to respond. We are able to stay calm when conversations get heated, when we are under pressure or we face last 8% moments. We aren’t as likely to run and avoid these situations or fight and make a mess of them.

  • We have better judgement. We are able to think things through more effectively in critical moments and make better decisions.

  • Finally, because we consolidated our experiences and learning into deeper parts of our brain, we are able to retain, and thus can retrieve more memory files. This is critical as we age. If you are finding that you can’t always find a word or remember an idea, sleep is one way to exercise your brain to get better at this.

What decrease sleep quality?

  • Alcohol: We might fall asleep a bit easier, but it is like exercising while drunk – we don’t get much done. Our critical neural activity goes down and our brain can’t achieve as much while we are asleep.

  • Shift work: Our body never really adjusts to working at night. People who are on shift work experience life as permanently jet lagged. Investigations of both The Space Shuttle challenger explosion as well as the Chernobyl disaster revealed they were associated with poor judgement due to sleep issues.

  • Caffeine: If you consume caffeine after 12 pm, your sleep quality will be negatively impacted regardless of whether you feel it. It’s best to avoid drinking coffee or energy drinks later in the day!

  • Sustained stress: Stress messes up our neural chemistry and has negative impact on cortisol, a stimulating, alerting hormone. Cortisol is highest in the morning where it helps to get us up and going, but should decrease throughout the day. If we are not managing stress effectively, cortisol levels can affect the quality and quantity of sleep.

How much sleep do we need?

Whilst there are various arguments in the literature,  generally between 7.5 and 8 hours are sufficient. However, the suggestion that we need less sleep as we age is a myth.

“It is a common experience that a problem difficult at night is resolved in the morning after the committee of sleep has worked on it.”
~ John Steinbeck

 


How can we  improve sleep quality?

  • Get data: Buy a Fitbit or some other tracking device and see for yourself what your sleep score is. This will be a wakeup call to the quality and quantity of sleep you are currently getting. There are two types of sleep - REM and Non-REM sleep, which is broken into light sleep and deep sleep : Light sleep is experienced during transition phases to deep sleep. Deep sleep is what makes us feel refreshed in the morning.  It occurs in longer periods during the first half of the night.  Your heartbeat and breathing slow to their lowest levels during deep sleep. REM occurs about 90 minutes after falling asleep.  Your eyes move rapidly from side to side behind closed eyelids. This is when we dream. 
  • Make it cool: A cool environment matters for sleep quality. Evolutionary speaking, we have been trained over millennia to sleep when the temperature goes down as the day turns to night. To this day, a decrease in temperature is a signal for our body to go to sleep. To prepare your body and brain for sleep, it’s advisable to turn the temperature down 30 minutes prior to going to bed. 
  • Make it dark: Throughout the evolution of the human species, our brains have also been trained to go to bed when it gets dark. On the flip-side, when it’s bright outside, parts of our brain get activated, releasing chemicals that make it harder for us to fall asleep and have high quality sleep. This of course includes our phones. Not shutting off our phones in time before bed has been proven to be one of the biggest contributing factors to poor sleep quality for most people.
  • Turn your bedroom into a sanctuary. As hard as it is, especially when we have been spending so much time at home during the pandemic: the bed should only be used for sleep, not activities such as work or watching television. This way we create the right associations for our brain to know what it needs to be doing.
  • Commit to a mindfulness practice: Research shows multiple benefits of mindfulness and its effect on sleep. If we are able to react in a wiser, more self-aware manner to events in our lives, we are able to manage stress and therefore our cortisol levels better. It becomes easier for us to calm down. One of the biggest culprits to poor sleep is overthinking and ruminating. Check some of our other blogs, podcast episodes or our Last 8% Academy for effective ways to build mindfulness.

  • Move more! There is plenty of evidence that exercise not only helps you fall asleep quicker but also improves sleep quality. Moderate aerobic exercise, for example walking for 15-20 minutes with our podcast, promotes deep sleep, which specifically helps our brain do its own exercise and rejuvenate our system. Exercise can also help stabilize our mood and decompress our mind. It’s important though not to exercise too close before bedtime, as it raises your core temperature – a signal for your body to wake up. You should finish exercising one to two hours, better yet at least three hours before going to sleep.

 

“In the end, winning is sleeping better.”
~ Jodie Foster