The Importance of Sleep

Sleep is vital to your health, well being and effectiveness. It's not a badge of honour to get little sleep, it shows how little you respect your health and how little you value your time. Sometimes the best thing you can do to increase your effectiveness is get a good night's sleep.

The Importance of Sleep

Scientists have discovered an amazing new treatment that makes you live longer. It enhances your memory and makes you more creative. It makes you look more attractive. It keeps you slim and lowers food cravings. It protects you from cancer and dementia. It wards off colds and the flu. It lowers your risk of heart attacks and stroke, not to mention diabetes. You’ll even feel happier, less depressed and less anxious. Are you interested?

If this ‘advert’ were for a new drug people wouldn’t believe it or they’d pay large sums of money for it. If it were a drug it would create a multibillion dollar business overnight. But it’s not for a wonder drug, this advert summarises the scientific findings of more than 17,000 well-scrutinised scientific reports of the benefits of a full night’s sleep.

Yet all too often we shun the nightly invitation to get a full night’s sleep - often with terrible consequences. By the end of this video you will understand the important role sleep plays, you will feel more able to take steps to increase the amount of sleep you can get and you will be able to make yourself feel better almost immediately.

How much sleep do you get on an average Monday - Friday? Less than 6 hours 6-7 hours, 7+ hours. How often do you wake, rested, without an alarm clock - midweek and at the weekend?

Most days, Only at the weekend or on holiday, Never ?

How possible do you feel it will be to change things about your life to give yourself the opportunity of a full night’s rest? Impossible? Difficult but doable? Fairly simple?

What are the challenges we face in getting a good night’s rest?

While some of those are more difficult to influence there are many factors that we can alter in order to maximise our chances at getting a good night’s sleep.

Inadequate sleep is related to 2 of our most feared diseases - Alzheimer’s and cancer.

Our Sleep quality reduces as we age, and that can be linked to a decline in memory, but this is much more exaggerated in Alzheimer’s patients. Sleep disturbance precedes the onset of Alzheimer’s by several years so it could be an early warning sign or a contributory factor. Sleep disturbance and Alzheimer’s interact in a self-fulfilling negative spiral that can initiate or accelerate the condition.

In terms of our Heart health - studies of more than half a million people show that progressively shorter sleep is linked with a 45% increased risk of developing and/or dying from coronary heart disease within 7 - 25 years from the start of the study.

In a Japanese study those sleeping 6 hours or less were 400-500% more likely to suffer one or more cardiac arrests than those sleeping more than 6 hours. The link remains strong even after controlling for other risk factors such as smoking, body mass, activity level.

In midlife our health resilience starts its decline in general but the impact of a lack of sleep on the cardiovascular system escalates this. People over 45years who sleep fewer than 6 hours a night are 200% more likely to have a heart attack or stroke during their lifetime, compared with those sleeping 7 or 8 hours. Unfortunately this coincides with the time when many of us are experiencing the most sleep pressure owing to career and family commitments.

It’s to do with blood pressure and it takes just one night sleep deprivation to inflict a measurable impact on your cardiovascular system even in young fit people. Cortisol also increases blood pressure so stress is an issue too. Our stress responses - controlled by your sympathetic nervous system - can operate like a car engine revved to shrieking point for sustained periods and stress leaks out in all manner of health related issues, increasing periods of sustained cardiac beating. So it’s a vicious circle.

Faced with all this evidence we need to find ways of making sure that most of the time we give ourselves an 8 hour sleep opportunity. But what happens in that 8 hours and why is it 8 hours that’s important?

Sleep is not merely an absence of wakefulness. It’s much more than that. It fulfils many different purposes. Numerous functions of the brain are restored by, and depend upon, sleep. No one type of sleep accomplishes everything. Each stage of sleep benefits the brain differently, at different times of the night. So no one type of sleep is more beneficial than another. Losing out on any one type of sleep will cause brain impairment.

The Stages of sleep are - NonREM and REM - play out in a recurring push-pull battle with the brain throughout the night. Each cycle takes roughly 90 minutes, ruled first by NREM sleep and then REM.

The ratio of NREM and REM sleep changes throughout the night. In the first half there’s more NREM, in the 2nd half the amount of REM increases.

We don’t know why this happens, but we know it also happens in all other mammals and birds.

A key function of NREM sleep is to weed out and remove unnecessary neural connections. Whereas REM sleep plays a role in strengthening connections. In this way sleep may manage and solve memory storage issues - our life is ever changing, never complete until it ends, demanding continual renewal and refreshment.

Sleep also improves out Memory. Sleep before learning refreshes our ability to make new memories. The hippocampus is key here, acting as a temporary store, but its capacity is limited and then we experience the overwriting of one memory with another and consequential forgetting.

Research supports the theory of memory transference. In tests 2 groups were divided into nap and no-nap groups, given taxing learning to do then allowed to nap or given menial activities to do. Those who didn’t nap became progressively worse at learning throughout the day, those who napped improved their Capacity to memorise facts - by 20%!

Research has shown that this type of refreshment of our ability to learn is associated with the lighter stage 2 of NREM sleep. During this stage it appears facts are shifted from the hippocampus to the cortex - long term storage function. The hippocampus is then cleansed and ready for the next day’s learning.

This process is specifically associated with sleep spindles which are more easily generated by the young than old and are more frequent in the late morning hours, sandwiched between longer periods of REM sleep. Sleep 6 hours or less and you are short changing your brain of all these learning restoration benefits.

Sleep after learning effectively clicks the ‘save’ button. It protects our memories. Research shows a lack of sleep leads to accelerated forgetting, with a memory retention benefit of between 20 - 40% being offered by sleep. This is not a trivial amount whether you’re revising for an exam or remembering details of client relationships.

The stage when this function is performed is the early night sleep, rich in deep NREM.

If this stage is interrupted at all, not even by waking, but just by infrequent sounds, keeping the brain in shallow sleep, then brain function is deficient and learning is impaired. Sleep deprivation also makes forgetting things a lot easier - things you might actually want to remember.

Though Forgetting is just as important as remembering. If you remembered where you parked your car every single day of your life then it would be more difficult to find it today. Sleep boosts our ability to remember important facts and forget unnecessary ones - again it’s NREM that’s responsible for this.

What I want you to think about now is what do you achieve in the hours between when you should go to bed to get an 8 hour sleep opportunity and when you actually do go to bed. So, if you get up at 6am, what do you achieve between 10pm and whenever you go to bed? Pause the video and think for a couple of minutes.

When I ask most people this question they say they just watch TV or are on their phone, or are faffing about. We’ve got to ask ourselves if what we achieve in that time is more valuable than our cardiovascular system, protecting ourselves from cancer and Alzheimer’s or even just making the most of the following day, being our best the following day.

Because Sleep also plays an important role in motor skill memory, such as riding a bike, playing the piano, doing a dead lift. The routine we go through as we execute these activities is the memory programme. Research shows that sleeping in-between learning a new skill and practising it again provides real gains, about - 35% greater accuracy. As soon as you sleep after learning a new motor skill then you get this gain, it doesn’t have to be immediately afterwards. So your brain continues to improve your skill even without any more practice. Check in with the Visualisation video in Resilience for more proof of this.

We’re back to stage 2 NREM sleep for this skill development, especially in the last 2 hours of an 8 hour sleep e.g. 5-7am if you’ve fallen asleep at 11pm.

The problem though is that Those last 2 hours are precisely those that many people feel are okay to miss out on Monday to Friday.

Sleep also creates an opportunity for your brain to link non-obvious associations in a way your waking brain would never attempt. When you’re awake and task focused your brain doesn’t get the same time to meander off. The sleeping brain fuses together disparate knowledge sets that foster impressive problem solving abilities. This generally Happens during REM stage - the dreaming stage.

So, those of you who said you regularly got less than 8 hours sleep, listen up at this point.

Sleep deprivation is catastrophic - in performance terms and in life expectancy. Concentration buckles almost immediately with only relatively minor sleep deprivation. Every single hour someone dies in the US in a traffic accident related to fatigue.

After 1 night total sleep deprivation - missed responses in research studies increased by over 400% - caused by microsleeps. Subsequent night’s sleep deprivation increased the error rates exponentially. No surprise really - sleep loss has been used as torture.

Partial sleep deprivation produces alarming research too. After 4 hours sleep for 6 nights participants performance was just as bad as those who had stayed awake for a full 24 hours - 400+% micro sleeps. By 11 nights their performance matched those who had pulled 2 all nighters back to back.

One group obtained 6 hours sleep a night - a period familiar with many of you, I’m sure. 10 days of 6 hours sleep was all it took to become as impaired in performance as going without sleep for 24 hours straight. And like the no-sleep group, that impairment didn’t level out, so if you carry on with only 6 hour sleeps then you just get worse and worse.

And another thing...you don’t know how sleep deprived you are when you’re sleep deprived. The participants consistently underestimated how sleep deprived they were, like drunkenness. People acclimatise to their impaired performance - low alertness, reduced energy - it becomes the accepted norm and people rarely link their sleep with how they are feeling over time. So many people spend their lives in a state of sub-optimal psychological and physiological functioning.

A client of ours came on one of our courses and told me that there was no way she would be able to get 8 hours sleep a night as she had too much to do. We looked at what she was doing between 10pm and 1am when she used to go to bed. It was general life admin and what she termed ‘faffing about’ - much of it to do with getting her children’s stuff ready for school. We spoke about how she could explain to her children how important it was to be responsible for getting their own things ready the night before, and then she started just going to bed at 10pm. She couldn’t believe the difference it made to her experience of life, she was glowing, delighted, full of energy, she said, ‘wow, life is so much easier’. It was great to see. When she feels her life getting a bit out of control now, it’s usually because she has slipped back into her habit of faffing at night and not getting to be on time to fit in the 8 hour sleep opportunity.

60 years of sleep research prevents Matthew Walker, author of Why We Sleep and a sleep scientist, from accepting anyone who tells him that they ‘can get by on just 5 or 6 hours a night just fine’.

You can’t redress the balance at the weekend - your performance does not return to that observed at the original baseline level.

An Australian experiment compared sleep deprivation with drunkenness. One night’s sleep deprivation impaired performance to the level of the drink drive limit (0.08% blood alcohol - same as UK). This is the factor that really hit home with our client we talked about earlier. Every day she was driving her children back and forth to school at the equivalent level of sleep deprivation with the drink drive limit. She couldn’t believe it.

Most people would also take a bit of weight loss if it was offered without oo much effort too. Listen up, those of you who would like to be a few pounds lighter. The less you sleep the more you are likely to eat and your body is less able to manage those calories effectively, especially the concentration of sugar in the blood.

Studies show that sleep deprived individuals are 40% less effective at absorbing glucose - a result that would make a GP immediately classify you as pre-diabetic, starting a rapid intervention programme to prevent the onset of type 2 diabetes.

It happens in 2 ways:

But mostly the latter. After a week of restricted sleep body cells start repelling rather than absorbing insulin, leading to a rising tide of glucose in the blood and a pre-diabetic state.

Weight gain in sleep deprived individuals is also to do with hormones. Inadequate sleep increases the levels of ghrelin, a hormone that instigates hunger, and decreases the levels of leptin a satiety- indicting hormone.

Participants who were sleep deprived in the study also ate 300 more calories per day. Scale that up to a year (even including a month’s sleep abundant holiday) and you get an extra 70,000 calories consumed - causing 10-15lbs of weight gain.

Sleep deprived individuals also eat more snacks. Sleep loss increases levels of a hormone specifically linked to your desire to snack.

It’s not that we eat more because we burn more calories just by being awake. There’s no real difference. A person who is deprived of sleep for an entire 24 hour period only burns 147 more calories than a person sleeping a full 8 hours.

Sleep and your immune system are linked too. That’s why your body will try and ‘sleep itself well’. Reduce sleep even for one night and your resilience is reduced. In a study in which people were deliberately infected with the flu virus, those who had a full night’s sleep the week before were far less likely to develop the flu. In those sleeping 5 hours or less the infection rate was almost 50%, those sleeping 7+ hours only 18%. Even if the individual is allowed to get full night’s sleeps for up to 3 weeks the immune system doesn’t get over a week of short sleep and return to full function quickly - a diminution of certain immune cells could still be seen a year later.

Which leads onto Cancer...

It doesn’t require many nights of short sleep before your body is rendered immunologically weak. Natural killer cells are your body’s secret service. If you are a threat to the body, they will hunt you, they will find you and they will kill you - including malignant cancer cells. You don’t want a shortage of these cells, but that’s what happens when you sleep too little.

People sleeping a single night of 4 hours reduced their killer cell count by 70%. One night! Let alone weeks, months, years. Faced with the massive scientific evidence in this regard Denmark has been the first country to pay damages to shift workers who have developed breast cancer.

Regularly sleeping 6 hours or less is associated with a 40% increased risk of developing cancer.

It’s to do with the sympathetic nervous system again and its ramped up response provoking long term inflammation. Cancer cells use this to their advantage, luring the inflammatory factors into the cancer mass to feed it. It can also cause the cancer to shear itself off and spread. Sleep deprived mice suffered a 200% increase in the speed and size of cancer growth - including an increase in metastasis - and it’s when cancer metastasises that modern medicine often becomes helpless.

So sleep deprivation actively helps cancer grow and diminishes our own body’s ability to fight it. It’s such a clear link that the WHO has now classified night time shift work as a ‘probable carcinogen’.

Are you converted yet? I’m sure you are but let’s hear more.

Sleep, or rather dreaming in REM sleep takes the sting out of emotional, difficult or traumatic events that have taken place, offering resolution in the morning. REM sleep is the only time in your 24 hour period when your anxiety producing molecule is shut off. So the emotional reactivation that takes place in dreams happens in a non-anxious brain.

Sleep increases the emotional processing in our memories and the inclusion of the rational part of our brain in processing those memories when awake. Remember we have different amounts of REM sleep throughout the night so we need to make sure we get a full night’s sleep to get the benefit of this processing.

Only those dreaming of the traumatic incidents get the benefit of this processing, it doesn’t happen during waking hours - or, unfortunately for people with PTSD, where anxiety producing molecule doesn’t switch off.

Sleep acts like a fine tuner, readjusting the brain’s instrumentation at night. Specifically in reference to facial expression - a sleep deprived brain cannot decode facial expressions with the same accuracy as a rested brain. But it’s worse, because those who are sleep deprived develop a fear bias believing gentle, even friendly faces are menacing. Think of the occupations of those who are generally sleep deprived: nurses, police, military, new parents, leaders... but if you’re part of a team and you’re sleep deprived you might be casting aspersions on people who are well meaning. And this might carry through to how you interpret emails or comments and we’re back in the personality refraction cycle where a single thought creates a mood, a mood creates a temperament which can create a personality. We need to carefully protect our sleep to stop this happening, and/or be super self aware so we know we’re doing it, or likely to do it, and take corrective action.

Sleep also increases the brain’s Creativity

During sleep the brain makes links that a waking brain wouldn’t think of. A dreaming brain is adept at getting ‘the gist’ of things, getting a big picture overview. When participants in a test were woken from REM sleep they were able to perform the tests seamlessly, their problem solving abilities increased 15-35% based on waking performance. Think of the age old wisdom, ‘sleep on it’. REM sleep is light sleep. When you nap, as an adult you tend to nap in REM sleep so if you’re tired and struggling to find a solution for a problem you might benefit from a light nap.

If you google how to get better sleep you’ll no doubt read about less alcohol, tech and caffeine. So What are the affects of alcohol, caffeine and tech on our sleep? Using tech for 2 hours prior to bedtime blocks the rise of Melatonin by 23%. It affects sleep quality with participants losing significant amounts of REM sleep and feeling less rested during the day. It creates a melatonin lag whereby it affects the rise of melatonin for days afterwards.

Alcohol is a sedative. It reduces activity in our pre-frontal cortex, the area which inhibits our behaviour. Alcohol sedates you out of wakefulness but it does not induce natural sleep, it is akin to a light form of anaesthesia - it fragments sleep, disrupting REM sleep and increasing tiredness.

Caffeine clearly inhibits sleep. Ensure you’re not having too much during the day and try not to have any after 2pm if you have trouble sleeping.

Waking from sleep is another factor that affects our health. How we wake is important which is why some apps have a ‘light sleep detector’ that wakes during light rather than heavy sleep and will wake you more gently.

When you are wrenched from sleep artificially by an alarm your blood pressure and heart rate spike. If you repeat this by using the snooze button then the effects are magnified. If you can get into a habit of going to bed at the same time and waking up at the same time every day, including weekends, then it’s a great habit to have as your body and brain will adjust and you will soon find yourself waking up around the time of your alarm and perhaps even being able to dispense with it.

A final thing we need to understand about sleep is that Nine hours a night is too much

The positive benefits of sleep are not linear. Once past 8 hours the benefits reduce again and those sleeping 9 hours a night are more likely to die from cancer and cardiovascular incidents than those sleeping 8 hours.

Lack of sleep is often lauded in the workplace, heralded as a sign of superhuman performance. It should not be. A study by the RAND Corporation showed that sleep deprived individuals cost their companies a staggering amount of money. $40bn in the UK per year, almost 2% of our GDP. KPIs often require traits that include: motivation, creativity, intelligence, emotional stability, teamwork - all things that are affected by a loss of sleep. Underslept employees are not going to drive your business forward - nor are you.

So, as we end this video carry out these actions:

Ask yourself - do I get an 8 hour sleep opportunity most nights?

If yes, well done, carry on. If no, ask yourself what you’re achieving between when you should go to bed and when you do go to bed?

Is what you’re achieving more important than all that we have spoken about just now. I doubt it.

Now ask yourself what do I need to do to promote higher sleep quality?

Is it to do with fresh air, alcohol reduction, no tech in the evening?

Now take action. Generally it is within our control to improve our sleep quality and quantity, it’s just that we don’t address it. Address it and your quality of life will improve.

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