Episode Notes:
Chronic sleep deprivation is considered to be a leading cause of almost every mortality cause, linked to many pathologies including cancer, heart disease, neurodegenerative diseases, hypertension, obesity, and many more. Acute sleep-deprivation also has significant health impacts, with just 19 hours of sleep deprivation providing equivalent cognitive impairment to being legally drunk.
In this episode, we’ll explore the dangers of sleep deprivation and provide a review of the circadian clock, sleep pressure, and factors that will influence the quality and quantity of your sleep. I’ll also share all the lifestyle changes I have implemented to optimize my sleep and 10 recommendations for you to immediately begin improving your sleep and optimizing your life.
Topics
[2:29] Sleep’s regulators: Melatonin and adenosine
[3:48] How caffeine affects the sleep/wake cycle
[5:42] Lifestyle influences on sleep: Blue light, daylight saving’s time, genetics, and more
[9:08] How much sleep do you actually need?
[11:20] Which is worse: Sleep deprivation or being drunk?
[12:49] Making sleep a priority: My sleep habits
[18:28] 10 things you can do to improve your sleep
Thank you all for joining me on this journey to lifelong health, happiness, and higher performance. And remember, always be grateful, love yourself, and serve others.
Teaser
In this episode… Amazingly, the brain has been shown to respond to light exposure within seconds, and physiological changes occurring within minutes. In a world dominated by screens and artificial light, we are constantly bombarded with blue light exposure that confuses our internal clock, resulting in sleep, mood, and emotional disorders…
Episode Intro
Learn II Perform: Practical lessons so that you can immediately learn to optimize your health, happiness, and performance.
Gratitude
As always, I like to start off each episode with an expression of gratitude to someone or something that has really improved my life. Today, I would like to give thanks to long time trainer, mentor, and friend, Steve Szilagyi. To me, Steve has always been an incredible resource for advice on everything from human physiological and powerlifting, to business and finance, to lifestyle and mindset. Best of all, he sets the gold standard and epitomizes what it means to be a high performer. In addition to being a major contributor to the development of Learn II Perform, he has really inspired me to take my circadian clock and sleep cycle more seriously. We’ve shared many conversations about life-optimizing habits, and he’s been living this lifestyle much longer than I have. So thank you to Steve for setting the bar high and demanding, inspiring, and empowering greatness with everyone you meet.
Topic Introduction
Alright, so moving onto sleep. Sleep deprivation is a well-documented problem plaguing much of the world’s population, especially among high performers and achievers. Most of my life, I adamantly defended the stance that “Sleep is for the weak,” “Sleep is a necessary sacrifice for success,” or that “if you aren’t willing to sacrifice sleep, you just don’t want it bad enough.” During my college years, I averaged less than six hours of sleep a night and worked relentlessly to fulfil my obligations and ambitions. I ignored the warnings about sleep deprivation and the news articles about how sleep is important. In my mind, people who prioritized sleep over success just didn’t get it. Well, it turns out that the people who prioritize sleep may get the last laugh and experience significantly healthier and longer lives.
So What’s the Bottom Line
No matter how healthy, active, or genetically-gifted a person may be, sleep deprivation can wreak havoc on human optimization. To properly understand what leads to and what constitutes sleep deprivation, we are going to look at three main topics:
1. The Circadian Rhythm and Sleep Pressure
2. Factors influencing the Circadian Rhythm
3. The consequences of Sleep Deprivation
1. The Circadian Rhythm and Sleep Pressure
Most people are aware of their circadian rhythm, the biological clock that governs a large portion of our lives. Physiological processes and mechanisms, including sleep, are largely regulated by hormonal patterns that form our circadian rhythm. In the context of sleep, the most important hormone may be melatonin, often referred to as the “darkness” hormone. In its basic form, Dr. Walker, professor of neuroscience and psychology at University of California, Berkeley, describes melatonin as a chemical messenger released into the bloodstream from the pineal gland to inform the body that it is time to prepare for sleep [1]. In essence, melatonin is about the anticipation and preparation for sleep, rather than the sleep itself [2]. Dr. Walker has a great metaphor for this: consider your sleep to be the Olympic 100m race. Melatonin is nothing more than the voice that says “On your marks, get set, go.” Contrary to popular belief, taking melatonin won’t improve your quality of sleep. But it may help you prepare for sleep as part of the sleep-wake cycle.
Now, for a lesser known influence on sleep, Dr. Walker describes sleep pressure as a continuous tracker for how long you have been awake. As you are awake, a neurochemical called adenosine continuously builds up throughout the day. As you remain awake longer, more adenosine builds up, resulting in a greater desire to sleep – that’s your sleep pressure. Conversely, when you sleep, adenosine decreases and the sleep pressure subsides [3].
This force can be combatted though, by the use of a widely popular and addictive drug, caffeine. The effects of sleep pressure are essentially muted by caffeine as it binds to adenosine receptors in the brain, preventing the brain from recognizing the buildup of adenosine. What’s amazing, is that caffeine has a metabolic half-life of about five hours, meaning it often takes five hours for the body to remove just half of the caffeine intake [4]. So after a late night of caffeine-fueled work, when the liver finally removes caffeine from your system, all the built-up adenosine molecules will immediately bind to receptors, running you into a brick wall of fatigue known as the “caffeine crash” [1].
So we’ve covered the two main forces of sleep – the circadian clock and sleep pressure. It is important to know that these work independently. The release of melatonin to signal sleep won’t happen during normal waking hours, even if you pulled an all-nighter. This explains the peculiar energy burst you may experience during the day after a sleep-deprived night. In the morning, you have the forces of melatonin and sleep pressure working against you, but in the afternoon, melatonin subsides and it is only sleep pressure you feel. However, when melatonin is secreted that night and your sleep pressure has elevated further, you are likely to then experience a significantly stronger urge to sleep.
To demonstrate the power of the circadian clock, consider this. A 2017 study published in Nature, the gold standard for scientific research, found a direct association between college GPAs and sleep/wake timing [5]. But here is the real kicker – the total amount of sleep wasn’t indicative of academic performance, but rather, it was the consistency of sleep timing that mattered. To follow this up, WHOOP conducted a study using data from 20,000 people, totaling about three million sleeps [6]. They also found that sleep consistency correlated with higher performance data, and postulated that it was a result of an observed increase in deep sleep, REM sleep, heart rate variabilities, and decreasing resting heart rates. This leads to the idea that following a consistent routine may be the critical link to improving sleep and optimizing performance.
2. Factors influencing the Circadian Rhythm
There are many factors that influence your natural circadian clock, let’s talk about some key ones. The one that really stands out: blue light. Our retinas are housed with light receptors that can detect blue light wavelengths that synchronize our biological clock to the solar day [7, 8]. This actually happens because daylight has a percentage of blue light, meanwhile the light rays at sunrise and sunset have lower frequencies of blue light. For this reason, exposure to sunrise and sunset can help prime the body to wake up in the morning and naturally prepare for sleep at night [9]. Amazingly, the brain has been shown to respond to light exposure within seconds, and physiological changes occurring within minutes [10]. In a world dominated by screens and artificial light, we are constantly bombarded with blue light exposure that confuses our internal clock, resulting in sleep, mood, and emotional disorders [11].
Another important factor comes down to eating habits, considering both meal contents and meal timing. A 2017 study attempted to determine if meal timing had an impact on the circadian rhythm and what they found was that meal timing promotes notable changes in glucose homeostasis [12]. While clock-driven hormones such as melatonin were not altered, they concluded that human physiological rhythms may be impacted by variable meal timing. A separate 2016 study came to the conclusion that “what, how, and when we eat” may influence gene expression and potentially serve as both a cause and solution of chrono disruption, which is the alteration of a normal circadian rhythm [13]. It is also a possibility that eating influences the biological clock through the vagus nerve, which is known as a key part of the gut-brain connection. A 2013 mice study observed that vagal mechanoreceptors influenced the biological clock, but not food intake itself [14]. Given that conclusion, it is still unknown the full impact of food intake on circadian biology.
Moving on, shift work and jetlag are two other factors that can create a misalignment with your circadian rhythm. Influenced by environmental changes during flight and adaptation to a new time zone and geographical location, there is a required adjustment that results in temporary disruption to sleep and biological patterns [15]. This serves as an easy explanation for the symptoms of fatigue, stress, and poor sleep associated with air travel. Interestingly, daylight savings time has a similar effect, with significant increases in heart attacks being reported following the daylight savings time transitions [16, 17].
Shift work is similar in the sense that it imposes a shift in circadian biology, forcing the body to adapt to a new timeline [18]. In overnight work, the misalignment between the biological clock and light exposure from the solar day can contribute to significant challenges for the body, potentially leading to disrupted sleep, among other health consequences.
And to close out this section, it is important to note that through biochemical individuality and unique genetic profiles, we all have slightly different dispositions to specific circadian rhythms. What works for one person may not work for someone else, so it is important to realize genetic influence on your biological clock. Dr. Breus, known as the Sleep Doctor, proposes in his book The Power of When, that there are four primary chronotypes that dictate the optimal biological timing for your life [19]. For your curiosity, he has even produced a short quiz online that tells you your type, at thepowerofwhenquiz.com [20]. Although the subjectivity of online questionnaires leads to skepticism, a 2019 review of almost 2,000 participants found that chronotypes reported through questionnaires produce equivalent results to those found in actual studies [21], so there may be some real value in taking a quiz to better understand your personal biological clock.
3. The Consequences of Sleep Deprivation
Before exploring evidence of the dangers of sleep deprivation, let’s establish an understanding of what constitutes sleep deprivation. The National Sleep Foundation recommends that adults get between 7-9 hours of sleep per 24 hours period [22]. However, this is different for everyone, and those with higher activity levels will require longer periods of sleep. It has widely been reported that the likes of LeBron James and Roger Federer get up to 12 hours of sleep per night, while Usain Bolt and Venus Williams report an average of ten hours per night [23].
Obviously, these are some exceptions of high performance athletes that require more sleep. But the general consensus is that about seven hours of sleep is required each night. And in most studies on sleep deprivation, six hours is typically used as the cutoff, with anything less being considered sleep deprived. So, now that we have kind of talked a little bit about what constitutes sleep deprivation, let’s look into the real dangers of sleep deprivation.
In Why We Sleep, Dr. Walker references a study conducted by Dr. David Dinges of the University of Pennsylvania [1]. In the study, subjects were required to respond to irregular light flashes over a ten minute period by pressing a button, in the Psychomotor Vigilance Test [24]. Prior to commencing the study, all participants completed the test after eight hours of sleep to establish a baseline. In the 14-day study, there were four groups of participants, one who slept eight hours each night for 14 days, one with six hours of sleep a night, a group with four hours of sleep a night, and finally a group that was subjected to 72 hours of sleep deprivation. The results are staggering.
While the 8-hour group maintained nearly perfect scores for the entire two weeks, the 72-hour deprivation noted a 400% increase in concentration lapses after only 24 hours of sleep deprivation, a drastic trend that continued for the following 48 hours. Meanwhile, the equivalent of 24 hours of sleep deprivation was observed after six days for the 4-hour group and ten days for the 6-hour group. In other words, it takes less than two weeks for just an hour of sleep debt per night to result in the equivalent cognitive lapses of a full 24 hour period without sleep. In addition, Dr. Dinges also reported observing microsleeps, moments of complete lack of awareness, as participants would completely fail to recognize some of the light flashes. This study demonstrates how quickly sleep deprivation can begin to impair concentration and other cognitive functions.
Another study referenced by Dr. Walker found that drivers are just as likely to experience off-road deviations after four hours of sleep as people that slept 8 hours but are at the legal alcohol limit [1]. In this study, just one night of sleep deprivation may impair you as much as being legally drunk. Meanwhile, a similar study conducted by an Australian research team concluded that 19 hours of sleep deprivation results in the same cognitive impairment of being legally drunk [25].
If that hasn’t scared you yet, let’s look at mortality causes. A 2011 study tracked nearly 500,000 people of varying demographics over a period of between 7 and 25 years [26]. Amazingly, they found that individuals with reduced sleep were associated with a 45% increase in developing or dying from coronary heart disease. Or how about this, a Japanese study of about 4,000 factory workers found that individuals sleeping less than six hours a night were between 350 and 500% more likely to suffer a cardiac arrest than those sleeping at least six hours every night [27].
This section could go on forever – sleep deprivation affects every aspect of your life. Without going into further detail, sleep has also be correlated to the silent killer, hypertension [28, 29], inflammation [30], neurodegeneration [31], increase hunger via increased leptin and decreased ghrelin levels [32], reduced immune system capabilities [33], increased stress via increasing cortisol levels [34], poor decision making [35], decreased strength and endurance [36], and other health issues including diabetes, obesity, and microbiome issues [1]. I realize that it is a long list, so for more information and supporting links, check out the show notes on the website.
Personal Experience
So, to tie this back in with my own life, as I mentioned at the start of this episode, I used to take sleep for granted, prioritizing literally everything else – homework, workouts, eating, relationships, and worst of all, getting caught up on social media. Without question, I underestimated the value of sleep when I was younger. As I advanced through college, I became increasingly aware of its importance, but I was so overloaded with academics, athletics, and extra-curriculars that I willingly chose to sacrifice sleep in order of doing everything I wanted to do. Now, I don’t regret it, but I certainly don’t miss those days of perpetual exhaustion, taking advantage of every 20 min opening in my schedule to catch a little shut-eye.
Later, after graduating and beginning my pro hockey career, I was finally able to adapt to a schedule built around performance. Hockey, training, sleep, and nutrition were my focus areas, and everything else, including my master’s degree, became secondary. While playing pro, I typically averaged between 7-8 hours of actual sleep per 24-hour period, meaning I was often in bed for 8-9 hours a day, sometimes longer. Now, since retiring from hockey, my daily sleep has reduced to between six and 6.5 hours a sleep per day, with 7-7.5 hours of time in bed. However, this drop off is expected, given the decreased sleep need with significantly less intense physical exertion.
Fast forward to the pandemic, I began to really take my sleep more seriously and make deliberate lifestyle changes to try and optimize this absolutely crucial aspect of health, happiness, and performance. My sleep hygiene comes down to one guiding principle: Sleep is a non-negotiable priority.
Rather than sacrifice sleep to work harder, I prioritize sleep to work more efficiently. It has been a complete shift in my approach. And now I am going to share with you all the things I do to try and optimize my sleep.
With sleep consistency as a top priority, I wake up at 5am every single day, no matter what. Even if I am exhausted, I will get up, begin my day, and then take an afternoon nap if necessary. Consistency as night is a bit tougher, but I try to be lights out by 9:30pm. I find that this timing works for me, but obviously that bed time is impacted by life from time to time. And in case anyone is wondering, in taking Dr. Breus’ chronotype quiz, I did in fact discover that I am a lion. Pretty cool, right?
Moving on, another important note about sleep timing, I deliberately schedule 12 days to adjust to daylight savings time, altering my sleep/wake cycle by just five minutes at a time. Starting November 1st, 2020, I woke up at 4:05am, which my body would have understood as being 5:05am previously. I also aimed for an 8:30pm bed time, rather than 9:30pm. For each successive day and to the best of my ability, I pushed these times back by 5 mins until I was back to a 5am and 9:30pm routine.
Next, my pre-bed routine – a series of habits that help me unwind and signal to my body that it’s time to prepare for sleep. Once preparing for bed, the first step is to turn off all devices and put my phone on airplane mode so that I have no disturbances throughout the night. Next, I turn on my essential oils diffuser for some supplemental relaxation and sleep triggers (my favorite pre-bed oils are lavender and sweet orange) [37]. Then, I like to play the guitar for about 10-15 minutes, which is a wonderful way to relieve stress and relax. Afterwards, I will do some form of breathing exercises and/or meditation, read for about ten minutes, and then write in my gratitude journal. Overall, this process usually takes around 30-45 minutes and has been super helpful at priming myself for sleep.
Here’s another important one: Since blue light has such a large influence on our biological clocks, I try to reduce blue light exposure as much as possible. All my devices are permanently set to night-time mode to reduce blue light exposure and I wear blue-light blocking glasses always while working on devices. I wear a pair by KLIM Optics that filters out 92% of light at 400nm and was purchased on amazon – I’ll share the link in the show notes [38]. I also have pre-sets on my phone an iPad that completely turn off blue light, what I call red mode, with a triple click of the home button. Within an hour of bed time, I will ensure this mode is on for any device use. As for the computer, I try to avoid use for at least an hour before bed and I watch almost no TV.
The other biggest influence on sleep has been meal timing. I feel that my sleep is significantly improved with early meals. So in addition to eating in a restricted window, I try to ensure that my last meal is completed by 4pm, with 6pm being the latest acceptable time. Unfortunately, life doesn’t always accommodate. On days where I am forced to eat later, I have observed a decrease in sleep performance and recovery with my WHOOP data.
Other aspects of my sleep hygiene include keeping my room colder than the rest of the house, ensuring it is dark in my room, sleeping with ear plugs if necessary, getting as much natural sun exposure as possible during the day (especially sunrise and sunset), and I take naps as necessary (ideally late morning or early afternoon). As life interferes with my sleep routine, I often am unable to be lights out by 9:30pm, often pushing 10:30/11:00pm. This is why naps become so important, because I refuse to let myself sleep in past 5am and I don’t want to have to try and overcompensate with an early bed time. So when my sleep is less than necessary, I schedule in naps to prevent sleep debt from accumulating.
So while it may sound like I am pretty anal about my sleep, I must admit that I am not perfect. I definitely have my fair share of bad nights of sleep and my routine isn’t always perfect. But after making these changes, I have become highly cognizant of how I feel when I sleep poorly and when I sleep well.
For example, when beginning the production of Learn II Perform, I was extremely excited, overwhelmed, and experienced entrepreneur insomnia for the first few weeks. I was up late into the nights working, so I started sleeping in to accommodate, and all my lifestyle habits fell apart. My focus and motivation dwindled in the afternoons, I spent way more time on social media, my workouts suffered, and despite being uber focused on this project, I was far less productive. I had a hard time getting out of bed, experienced the return of brain fog and just wasn’t myself. After a few weeks, I set the alarm for 5am again and made sleep consistency my top focus. Since then, I have felt way better, have higher levels of energy, am far more efficient and productive despite spending more time in bed, and have become a true believer in the value of sleep.
So What Can You Do
It is clear that sleep deprivation has dangerous consequences, not just by preventing human optimization, but by threatening your life. A huge part of healthy sleep corresponds with your biological clock, so I am going to share my best tips to optimize your circadian rhythm, improve your sleep, and optimize your life. Here are ten things you can begin doing right away.
1. Reduce blue light exposure
• Avoid screen usage before bed
• Reduce blue light exposure
• Adjust settings on your devices to reduce blue light, and
• Wear blue-light blocking glasses when exposed
2. Get exposure to natural sunlight
• Sunlight can significantly help align your biological clock
• Also, sunrise can help to give you energy and sunset can help you prepare for bed
3. Wake up and go to bed at consistent times
• To the best of your ability, aim for the same time EVERY DAY (including weekends)
• Your body will thank you
4. Sleep in a cool, dark room
5. Eliminate distractions at night
• Turn off devices and notifications
• And although you may find it easier to fall asleep to Netflix, the lights and sounds are a source of stimulation that disrupt your natural rhythm, even with your eyes closed
6. Develop an evening routine to unwind
• Reading, journaling, stretching, meditating and breathing routines are excellent practices before bed
7. If sleep deprived, try to incorporate a nap to make up for sleep debt
8. Avoid caffeine within six hours of going to bed
9. Eat your final meal earlier in the day, at least 2-3 hours before going to bed
10. Test out your chronotype at thepowerofwhenquiz.com
If you guys have any other sleep tips, please let me know or feel free to share them with others! Getting quality sleep shouldn’t be complicated, but unfortunately our high-paced, tech-driven world has made it far more difficult to get quality sleep.
Finally, if you’re wondering if you are sleep deprived, Dr. Walker has a few questions to guide you [1]:
• First, after waking up, could you fall asleep by 10 or 11am?
• Secondly, do you need caffeine to function optimally before noon?
• And finally, would you sleep way past your alarm in the morning?
If the answer to any of those is yes, it could indicate sleep deprivation and the need to prioritize sleep in your life.
So with that, let’s close this chapter with a friendly reminder from Arianna Huffington, as she says “Everything you do, you’ll do better with a good night’s sleep” [39].
Episode Outro
To discover more, the full transcript of this episode with all citations is available on the website and you can also contact me on social media with any questions or comments. If you found this episode useful or think that it may help someone else, I encourage you to pass it along.
Thank you all for joining me on this journey to lifelong health, happiness, and higher performance. And remember, always be grateful, love yourself, and serve others.
References
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