Recently I was listening to a podcast in which the host posed a fairly stereotypical question: “If you could choose one exercise to do for the rest of your life, what would you pick?”
The interviewee responded, “SLEEP.”
Strong answer, I couldn’t agree more. Training and nutrition aren’t appealing to everyone even though they are fundamental tenets responsible for health and wellness.
However, regardless of age, gender, or ethnicity, everyone must sleep.
Sleep deprive anyone long enough and literally every physiological characteristic will deteriorate – cognition, rate of force development, circulating hormonal concentrations, insulin sensitivity, etc.
Some recent studies have likened sleep to a “dish washing cycle for the brain” in which toxic metabolites are removed and neural connections are strengthened.1,2
Despite all the current public health efforts to improve sleep education, students are still some of the most sleep deprived individuals walking the planet. Ironically enough, I’m writing this article on 2.5 hours of sleep so I’m well aware of the first-hand effects of sleep deprivation as a student.
Hammer Home The Basics
Sleep is a personal favorite of mine - not just the physical act of sleeping, I also really enjoy learning about the neurophysiology of sleep. As such, I’ve written about the topic extensively and would highly suggest you read all of the following before proceeding:
- Sleep Science: Nature's Most Effective Performance Enhancer
- Sleep Science: Nature's Most Effective Performance Enhancer (Part 2)
- Hacking Your Sleep 101: Nine Tips For Better Gains
However, I understand that most students are extremely busy and would rather fill their free time with Snapchat stories or Twitter beef. So, I’ll include a quick and dirty list for those with exceedingly short attention spans:
- Always get an apartment on the top floor of the building. ALWAYS.
- Sleep with an eye mask or black out curtains to remove any ambient light.
- Turn your phone on Do Not Disturb after 10pm. All those Facebook notifications can wait, trust me.
- Don’t check your phone in the middle of the night. You’re an adult, have self-control.
- Utilize a white noise app on your phone or purchase a high-quality sound machine (here is what I personally use and recommend).
- Get exposed to bright light first thing in the morning to set circadian rhythms.
- Stop sleeping with the TV on. Set a timer or turn it off after 8pm. Stranger things will still be there in the morning.
- Eat a high protein breakfast to enhance conversion of tryptophan to melatonin later in the day.
- Establish a routine sleep cycle in which you wake and sleep at the same time each day.
- Try to go to bed during double digits (e.g. 10pm) and avoid single digit (e.g. 1am) nights whenever possible.
- Tweak the settings on your phone to reduce blue light exposure late at night. Start here:
If you have these variables locked down, then perhaps it’s time to dig a bit deeper…
Find the Beat, Stay in Rhythm
Have you ever wondered why the sun sets each day? Why do we prefer to sleep when it’s cold and dark? Sure, you can sleep during the day and individuals who work night shift are often forced to alter their circadian rhythms due to their careers.
However, if you examine sleep cycles at a physiological level, we typically see certain hormonal swings based upon light or sound exposure and temperature regulation.
During a typical light/dark cycle, melatonin secretion begins between 9-11 pm, reaches a peak between 1-3 am, and falls back to baseline around 7-9 am.4,5 Furthermore, melatonin production is even higher in cooler environments (62-68°C).8 Similarly, the opposite is true, as cortisol concentrations rise in the morning, body temperatures increase to induce wakefulness.8
These hormonal swings are commonly referred as “circadian rhythms” which are ultimately governed by a central modulator in the brain known as the suprachiasmatic nucleus. Over the course of a 24hr day, you will typically see a variety of fluctuations in multiple systems11:
Body Temperature: 96.8°-100.4°
Heart Rate @ Rest: 5-25bpm
Stroke Volume/Cardiac Output: 5-23% of mean
Blood Pressure: 10-20/10 mmHg
Circadian rhythms are typically very tightly regulated provided an individual has a normal daily schedule and goes to bed at roughly the same time. However, there are many different factors which can dysregulate them over time.
1. Be Very Careful With Autonomics
Have you ever noticed that some days you’re exhausted sitting at your desk, willing yourself to keep your eyes open; but as soon as you get into your car and crank up your favorite song, all that lethargy seems to magically disappear?
This is the beauty of autonomics, it’s a double-edged sword. If you understand factors which influence autonomics, you can use them to your advantage. However, if you abuse these systems, you will quickly discover a variety of acute and chronic consequences. In the case of circadian rhythms, 2 of the largest modulating factors are:
These are typically referred to as “Zeitgebers” (aka “time givers”) in the literature. To quote a recent study:
Circadian rhythms persist in the absence of external stimuli, but they may be modulated over time by external cues, or ‘Zeitgebers’ (‘time givers’), the most important of which is light.9 Other ‘Zeitgebers’ capable of resetting the clock include ambient temperature, feeding and social interaction.10”
Most folks neglect this “time giver” by spending the majority of their night looking at a screen. Simplistically speaking, this is the easiest way to shift your circadian rhythm seemingly overnight and alter sleep quality and quantity. This figure should help to explain the physiology in a bit more depth.
Takeaway: Be aware of bright light exposure, especially late in the day (library, gym, etc.) Seek to reduce ambient light exposure later in the day and be careful with high intensity activities which overload the somatosensory system (weight lifting, loud music, contact sports, etc.) and may delay sleep.
2. Stop Relying on Supplements
Americans love a “silver bullet” mentality. Why change your lifestyle if you can just take a pill which solves all your issues, right?
Make no mistake, specific supplements CAN help. But, you must be very (and I mean VERY) careful where you source those products from. All supplement companies are not created equal. As one recent study noted when looking at the difference in melatonin content amongst 30 commercial supplements:
“Melatonin content was found to range from −83% to +478% of the labelled content. Additionally, lot-to-lot variable within a particular product varied by as much as 465%. This variability did not appear to be correlated with manufacturer or product type.
Furthermore, serotonin (5-hydroxytryptamine), a related indoleamine and controlled substance used in the treatment of several neurological disorders, was identified in eight of the supplements at levels of 1 to 75 μg. Melatonin content did not meet label within a 10% margin of the label claim in more than 71% of supplements and an additional 26% were found to contain serotonin.”
I use and recommend melatonin because it can be very useful to shift circadian rhythms if they get jacked up. However, you must realize that it is a hormone and as such, you need to be careful in how and when you consume it.
Don't assume you can out supplement a lifestyle issue - if you toss back 5g of melatonin but you're still blasting your retinas with Instagram and Game of Thrones after 8pm, you're shooting yourself in the foot.
Also, here's something else to consider: roughly eighty percent (EIGHTY, as in 8-0) of your melatonin production occurs within the gut.6,7
You see, approximately 90% of your body's serotonin is located inside the enterochromaffin cells in the GI tract. However, as I discussed in a prior article, serotonin is later converted into melatonin via specific biochemical pathways. Thus, GI integrity is more important than ever if you want to ensure adequate endogenous melatonin production.
Still think you can pound pizza rolls, eggo waffles, and zebra cakes? Yeah, you can and your body composition may (key word: MAY) improve provided you understand other aspects of health and wellness.
However, keep in mind that everything you eat alters the composition of your gut microbiome – if you eat crap long enough, you shouldn't be surprised when your crap changes (literally).
If you neglect gut health, don’t be surprised if you see other physiological tenets drop off – Are you able to sleep through the night? Do you find you’re easily stressed or your mood is altered? Do you wake more than once to urinate? Do you typically dream? Has your stool frequency or consistency changed? How about GI motility?
Remember, body composition is only one piece of the puzzle. Just because your abs look good on Instagram doesn’t mean that you’re actually healthy.
“Abs don’t equate to health. Trust me.
Couple years back, I was 220lbs with abs and 10% body fat. AND pre-diabetic.
Often abs are a mere illusion of health. A mirage of chiseled granite built upon a foundation of dust.
Just because you CAN eat like an idiot and be/get lean, doesn’t mean you SHOULD. Nature always wins and the resiliency of youth that it has blessed you with will eventually fade.
Eat real food and pursue health over abs. Let the vanity and aesthetics come as a nice by-product. The fundamentals will dial everything else in.
Health is a long-term game. Play it accordingly.” – Andrew Ferreira
Takeaway: Fix your lifestyle, don't let your environment dictate your physiology. On the contrary, understand physiology to better adapt to your environment and enhance adaptation.
Sleep and nutrition are innately tied - don't think you can eat like a child and expect to sleep like an adult.
Awareness precedes change, now you know.
- Sleep drives metabolite clearance from the adult brain.
- Sleep facilitates clearance of metabolites from the brain: glymphatic function in aging and neurodegenerative diseases.
- Melatonin Natural Health Products and Supplements: Presence of Serotonin and Significant Variability of Melatonin Content
- Melatonin: both master clock output and internal time-giver in the circadian clocks network.
- Melatonin in humans.
- Gastrointestinal melatonin: localization, function, and clinical relevance.
- Localization, physiological significance and possible clinical implication of gastrointestinal melatonin.
- Effects of thermal environment on sleep and circadian rhythm
- The human circadian clock entrains to sun time.
- Non-photic signaling in the suprachiasmatic nucleus.
- The significance of circadian rhythms and dysrhythmias in critical illness