It's about quality, not quantity
Note: Justin also gave a webinar on this topic for our audience, and you can watch the recording here.
Look, I know you’ve heard it before: good sleep is the missing ingredient for fat loss, muscle gain, improved performance, and world peace. If you’re looking for a cure to just about everything, start by looking at your sleep.
It doesn’t take a deep look at the research to understand this. A study in the Canadian Medical Association Journal took two groups, one sleep-deprived and one non-sleep-deprived. The non-sleep-deprived group lost on average 4 more pounds than the sleep-deprived group.
Another study from the University of Chicago had two groups on a calorically restricted diet. In phase one participants had 5.5 hours of sleep, in phase two, they had 8.5 hours of sleep. This group lost 55% more body fat in phase two than in phase one. And as you know, fat loss normally only gets harder as you make progress.
A UC Berkeley study showed that just one night of sleep deprivation decreased activity in the prefrontal cortex. In fact, there was a 15% decrease in glucose to the prefrontal cortex.
Now, the prefrontal cortex is responsible for higher-level decision-making. So when it’s partially shut down, you make stupid decisions. In fact, the size of our prefrontal cortex is pretty much what separates our brains from other monkeys, so if you’re not using it, you’re basically a monkey.
(As an aside, teenagers have underdeveloped pre-frontal cortices, so if you’re wondering why they make so many stupid decisions, it’s because the human part of their brain is still under construction. Think back to the dumbest decision you made in high school. Shudder at the thought of how stupid you were. Well, you might do something equally stupid if you’re sleep-deprived.)
Another study on college students showed that those who get less than six hours of sleep did worse on tests than binge drinkers and marijuana users and were more likely to drop out. So do drugs, but get some sleep (kidding).
I know, you’ve probably heard all of this. But it’s not the full story. When you take a deeper look at the research, you realize that low-quality sleep is not nearly as valuable as high-quality sleep. Thus, by optimizing quality sleep, you can avoid the pitfalls of sleep-deprivation without devoting your life to sleeping like a koala.
It’s’ the quality of sleep that really matters. You can actually get less sleep, but if that sleep is of higher quality, you feel, perform, and shed fat like somebody who sleeps like it’s their job.
But first, we need to define what we mean when we say higher quality sleep. Because while you’re sleeping you don’t know the difference.
There’s a big difference between being ‘passed out’ (on the overpass, Sunday best and broken glass) and actually getting quality sleep.
Ideally when we sleep, we’re not just laying on the bed passed out and in light sleep (as often happens when you drink too much alcohol), instead we’re going through a few sleep cycles. A full sleep cycle is 90 minutes, and includes the following four stages:
If a significant portion of your sleep isn’t in slow-wave and REM sleep, it doesn’t matter how many hours you’re passed out on the pillow, your body won’t recover and you’ll still feel like shit. In “quality” sleep, you’re effectively going through all the stages of a 90-minute cycle.
(Another aside: In particular, the FIRST 90-minute sleep cycle is most important because this is when your body produces the most growth hormone (GH). GH, which you can read about here, helps with everything, from anti-aging and fat loss to muscle gain. It also helps preserve muscle, making it like a hug around the muscle you already have. Getting to sleep between 10pm and midnight is key because that’s when the most HGH is secreted.)
Okay cool, Justin, but how do we improve our sleep cycles? While there are lots of strategies we’ll get into, the foundation for understanding the different methods begins by understanding the cortisol-melatonin cycle.
Cortisol, which has been bastardized in the last few decades as an evil stress hormone, is not inherently evil. In fact, we need cortisol. It’s one of the main hormones that help us get out of bed in the morning and energize us throughout the day. Cortisol gives us that get-up-and-go energy.
Cortisol is not an evil stress hormone,, it just needs to follow its natural cycle.
When your body (and sleep) is dialed in, your cortisol levels rise highest in the morning, right around when you wake up. As the day progresses, cortisol levels drop, reaching their lowest point when you go to bed. Then throughout the night, cortisol slowly rises, until you have enough of the energy-inducing cortisol flowing through your veins to get your butt out of bed.
Melatonin is the inverse of cortisol in just about every way. It’s the hormone that allows us to relax, go to sleep, and stay asleep. As such, melatonin’s natural rhythm is the complete opposite of cortisol. It’s at its high point right before bed, then as you wake up it trickles back down.
Now this sounds nice and all, but a lot of times our cortisol-melatonin cycle is out of whack. Or, even if it’s slightly off, with just one or two simple changes you can ensure your sleep quality is optimal. There are umpteenth number of factors that can affect melatonin and cortisol that can disrupt this natural pattern.
(Read here how you can get the most out of your wearable device.)
With your wearable device, you can assess the quality and quantity of your sleep on a nightly basis. More importantly, when you make subtle changes to your sleep routine, having your sleep data allows you to assess its effectiveness and perform mini-experiments on your sleep.
A lot of common lifestyle routines cause the cortisol-melatonin cycle to flip. Your cortisol is higher at night than it should be, and your melatonin remains high in the morning. If you’ve ever felt wired before bed, like all of the sudden you could run a marathon, and then so tired in the morning that getting out of bed is a monumental struggle, you’re a victim of an out of whack cortisol-melatonin cycle.
“Tired and wired” is a situation you want to avoid.
In serious, chronic instances (hopefully not you), an out-of-whack sleep hormone cycle causes people to turn to stimulants in the morning to get out of bed, and sedatives to wind down. If you need excessive caffeine to function in the morning and exogenous melatonin to fall asleep, you’re setting yourself to have serious health problems down the road.
When your cortisol is elevated at the wrong time, it leads to an effect known as gluconeogenesis, which is a fancy word to say your body breaks down your muscle tissue for energy. And, when your cortisol is high at night, your body won’t produce as much growth hormone, which helps shed fat and preserve muscle.
Poor sleep also messes with the main hormones responsible for managing hunger: leptin and ghrelin. Leptin is the satiating hormone (and a key factor for why cheat days can work). Ghrelin is the hormone that makes you hungry. One bad night’s sleep will cause ghrelin to increase, and leptin to decrease, and after one night of poor sleep people eat on average 250 more calories the next day.
If you’ve ever been in this insatiable state, you know you probably didn’t go grab the chicken and rice. Instead you ate whatever you could get your hands on: candy, chips, and other junk (or maybe a whole jar of peanut butter). These hormonal factors are why sleep is so important for fat loss.
During our deep, slow-wave sleep, our glymphatic system goes to work. The “G” system is responsible for clearing waste products from the brain (University of Rochester Medical Center), and is ten times more active during deep sleep than during the day. Sleep’s impact on the glymphatic system (which was named in just 2013, so we’re still learning more about it) may be a huge reason why persisted sleep deprivation leads to an increased risk of Alzheimer’s, dementia, and memory loss.
REM sleep, which we also don’t know a ton about, has been shown to play a crucial role in consolidating memories. If you can’t get into REM sleep, you’ll have a hard time remembering the events of the prior day.
Not that you didn’t know this, but hopefully now you have a better understanding of why you need to get quality sleep. But none of this matters unless you actually have new strategies you can use to improve the quality of your sleep without making your sleep schedule control your life. So, here are some simple action steps you can take to improve your sleep.
The problem with caffeine is that a lot of the time you can still fall asleep normally under the influence of caffeine, but it will prevent you from getting into deep sleep and REM sleep.
Caffeine has an average half-life of 5 hours (this can vary for individuals, ranging from 1.5-9 hours). If you remember this from high school chemistry, this means that after five hours, HALF of the caffeine in your body is gone. If you have a cup of coffee with 200mg of caffeine at noon, at 5 o’clock there’s still 100mg active in our body. That’s why we have to have a caffeine cutoff. And it’s probably earlier than you wish it were.
In one study, three groups had caffeine 3 hours before bed, 6 hours before bed, and right before bed. Even in the group that had coffee six hours before bed they still lost about one hour of quality sleep. Even six hours before bed, the study showed that one hour of quality sleep was lost.
Here’s where people mess up their caffeine intake though:
Even if you don’t think your late afternoon caffeine intake is affecting your sleep, it very well might be, and the only way to know for sure would be to track your sleep with your wearable device.
For most of us, our caffeine curfew should be around noon. This can vary depending on when you go to bed and how well your body metabolizes caffeine, but the only way to play around with this is to run self-experiments and look closely at your sleep data with your wearable device. But noon is a good default starting point.
If we use caffeine first thing in the morning it can become a cycle where we need caffeine to get us up and keep us going, leading to chronic negative sleep effects.
Often caffeine usage is a part of the vicious cycle. You use it to get your day started, to keep your day going, and to not crash at night. Then, it keeps you awake so you may need a sedative to wind down. However, caffeine can be used to improve our sleep rhythm.
Caffeine increases your cortisol levels, which means if you want caffeine to work for you, it’s okay to have some in the morning when we want our cortisol levels to be high. Or, you can have some before you train (ideally in the morning also) because cortisol can increase your performance. However, the more often you have caffeine, the more these potential benefits get dulled. So, caffeine from time to time can increase cortisol and help reset your cortisol-melatonin cycle.
Another valid strategy is to cycle your caffeine usage. You can use caffeine for a few days in a row, but then take about 3 days off. When you take time off of caffeine, your body’s caffeine receptors downregulate, Then, just a little bit of caffeine can give you the jolt of energy you need, when you need it.
Before there was artificial light, our species evolved to wake and sleep based on how much natural light was around us, and in what colors. Blue light, like the sky, tells our body that it’s the daytime, whereas red light, like a natural fire, along with darkness tells our body that it’s nighttime. Our body will secrete hormones depending on what time of the day it thinks it is.
In one study, for every hour of use on our devices after the sun went down, it led to 30 minutes of suppressed melatonin. So if you watch 3 hours of tv before bed, that’s 90 minutes of melatonin suppression, a whole cycle of quality sleep. And this is the first cycle, the one crucial for growth hormone secretion.
Blue light during the day when cortisol should be high is a positive, but it will keep your cortisol elevated and suppress melatonin secretion at night. The next step is to find simple strategies to mimic what our light exposure naturally would be.
In an ideal world you shouldn’t use screens at night. However, I know that pretty much all of us use screens at night. I think it’s a modest request to ask you to put your screens away around one hour before bed. Pick up a book. Talk to your loved one. Have sex. All of these things are much better than watching TV or scrolling with TikTok anyway, and they have the added bonus of aiding your sleep rather than harming it. The one-hour rule is arbitrary here, as the literature says you should be off screens for much longer. But talking practically, one hour is a good place to start, and then you can use your sleep data to experiment further.
From the time the sun goes down until the hour before bed (or if you have to work into the night, which happens) then you can set your screens to emit much less blue light. The first step is to turn on night mode on your devices. You can take this even a step further. Both on your Mac or iPhone (I assume your PC and Android can do this too if you’re one of those weirdos), you can make night mode, even more like nighttime. You’ll want to adjust your night mode settings to be as red as possible, therefore emitting more red/orange light and less blue light.
You can also set the screen to Grayscale and lower the overall brightness. Both of these will continue to lower the amount of blue light. As a bonus tip on the Iphone, you can set the “triple-click” feature on your home button to move to grayscale. That way you can easily change back and forth between color and no color. The grayscale feature has also been shown to make your phone less addicting, which is not only just a benefit for your life and productivity, but it will make it easier for you to get off your phone when it’s time to put it away.
If you’re placing the settings on your phone and computer correctly, and getting off your screen an hour before bed, the occasional late-night use of a device won’t kill you. However, if you regularly work at night, then it’s worth looking into blue light glasses.
The problem with most blue-light-blocking glasses is they don’t look cool. And that’s a problem. However, if you’re regularly working on your computer at night, they’re key and will be just another layer of protection against blue light.
(Note: Don’t use blue light blocking glasses during the day, because that’s when you want blue light.)
You can do some research to find different ones. In general, the better looking they are, the less effective they’ll be. Which is obviously not the combo we want. One great option that look awesome and are quite effective are the Bucci-Klassy blue light blocking glasses (yes, we’re biased in this recommendation because Amanda Bucci is the best).
I like simple. If routines are complex, people don’t follow them. So here’s what I recommend to my clients in their nighttime routine: Three hours before bed should be your last heavy meal (snacking is okay). Two hours before bed you should stop all work. One hour before bed you should turn off all screens and aim to eliminate blue light.
A study done at Appalachian State split people into three groups. The groups exercised at 7 am , 1pm, and 7 pm respectively. The morning exercisers had more time in the productive stages of sleep (REM and deep). The logic is simple: training in the morning increases your cortisol in the morning, thus setting up your cortisol-melatonin cycle for success.
If you still want to do your afternoon workout, that’s totally fine, but add some type of movement to the start of your day. If you can make 5-10 minutes of movement as part of your morning routine, you’ll be supporting that cycle and improve your sleep in the long-term. As a bare minimum, just do 20 reps of something. 20 push-ups. 20 squat jumps. 20 of anything to get your body moving and cortisol pumping. (Morning sex, anyone?)
Another study showed that if you worked out within 4 hours before trying to go to sleep, you had an increase in body temperature, cortisol, blood pressure, and therefore a decrease in melatonin and sleep quality. If possible, you’ll want to have a cutoff for your workouts around 4 hours before you go to bed.
Another way to level up here is to try to get sunlight first thing in the morning as well. That again will send the signal to your circadian rhythm to increase cortisol in the morning and then drop it off later in the day.
The American Association of Sleep Medicine found that a group of insomniacs that had to meditate in the middle of the day (10am-2pm) for 8 weeks were no longer sleep deprived by the end (American Academy of Sleep Medicine).
I’m surprised we’ve made it this far without getting into a discussion of brain waves, but effective meditation slows our brain waves down. Our brain waves range from the following categories, listened from the shortest and fastest to the slowest and longest:
GAMA – while we’re in “high-performance” mode and thinking deeply
BETA – our everyday waking and thinking brain wave
ALPHA – more of a resting state, but easily obtained during meditation
THETA – we mostly only get here during sleep, but in some deep meditation we can get here
DELTA – deep sleep
In deep sleep, our brain gets into “delta” brain waves, which is why it’s also called slow-wave sleep. While we meditate we can slow our brain waves and enter ALPHA and even THETA waves.
Meditation also has tons of other benefits which in turn improve sleep, such as reducing stress, helping us stay in the present moment, and activating our parasympathetic nervous system.
A discussion on improving your sleep wouldn’t be complete without talking about how our nutrition also impacts us. Talking about the gut is kind of a new-age thing that everybody is talking about these days. And the jury is still out in so many areas with regards to how our gut microbiome affects us. That said, there seem to be a few nutritional areas that in particular help with sleep.
We’ve learned that melatonin is highly abundant in our gut, which suggests that a healthy gut means we’ll produce more melatonin at night time. To my estimates, we don’t fully understand these mechanisms yet, but it can’t hurt to eat to support your gut health. That means including prebiotic foods like onion, garlic, honey, apples, bananas, to name a few prebiotic options.
Magnesium is responsible for 300 processes that go on in the body. And, around 68% of us are deficient. It plays a critical role in sleep and recovery, and it’s not so easy to get from whole foods. So, consider adding a magnesium supplement. Potassium is equally important for the sleep processes, in particular for helping you stay asleep through the night.
I’ve just thrown a lot of variables at you. It may be tempting now to try to completely re-engineer your nighttime routine to start sleeping like a hibernating bear tomorrow. But, I would actually advise you against this. Changing a ton right away will cause a few problems. First of all, it will be too much of a shift all your habits at once. When you do this, it’s more likely that none of it will stick. Secondly, you won’t know what’s actually helping your sleep because you’re not isolating variables.
From all of these possible options, choose one that you feel you can implement without disrupting your routine too much. Hell, just turn on grayscale if you want. Then, look more closely at the sleep data on your wearable device to assess its improvement on your sleep quality.
Slowly over time, you can integrate one habit at all time, until eventually you’re sleeping like a pro. Notice, I didn’t say anything in this article about the need to sleep 8 hours. Yes, I don’t want to deny that sleep quantity to an extent is important, but if you can take the quantity you’re getting right now, and just improve the quality, your performance, muscles, mindset, brain, everything in life will improve.