Maximizing Productivity, Physical & Mental Health with Daily Tools | Huberman Lab Podcast #28
- Welcome to the Huberman Lab Podcast, where we discuss science and science-based tools for everyday life. [upbeat music] I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today, we're going to talk about science-based protocols for sleep, mood, learning, nutrition, exercise of various kinds, strength and endurance, and hypertrophy, and we are going to talk about some protocols that relate to creativity. We're going to talk about behavioral protocols, supplement based protocols, all science backed by quality, peer-reviewed literature. The reason that we're holding this episode now is that in the recent previous episodes, we've covered some pretty intense and in-depth topics.
We've talked about vision and how we see and how to get better at seeing and how to maintain vision. We've talked about hearing and balance. We've talked about chemical sensing. And we had a guest episode that covered a lot of information about new and emerging technologies in neuroscience, as well as mental health. That was the interview episode with Dr. Karl Deisseroth. So given that we've covered so much detailed information in the previous 27 episodes of the Huberman Lab Podcast, I decided that we would hold office hours.
Office hours in the university setting are when students come to the professor's office or you meet outdoors on campus or in the classroom to review the material and questions from lecture in more detail. Now, unfortunately, we don't have the opportunity to meet face to face in real life, but nonetheless, you've been sending your questions, putting them in the comment section on YouTube, et cetera, and I prepared a number of answers to the questions that have shown up most frequently. Now, in order to provide context and structure to the way that we will address these questions, I've arranged the science and science-based protocols that relate to various aspects of life- such as mood, exercise, sleep, waking, anxiety, creativity, et cetera- into the context of a day. Selecting the unit of a day in order to deliver this science information and protocols is not a haphazard decision on my part.
It's actually the case that every cell in our body, every organ in our body, and our brain is modulating or changes across the 24 hour a day in a very regular and predictable rhythm. And it's no coincidence that the Earth spins once on its axis every 24 hours. These two things are coordinated by virtue of genes and different proteins and things that are expressed in every cell of your body. And so selecting the unit of the day is not just a practical one, but it's one that's related to our deeper biology. You may have heard in my interview episode with Dr. Karl Deisseroth that he himself,
in order to juggle a tremendous workload, a full-time clinical practice, a lab of 40 plus people, a family of five children, et cetera, breaks up his life into units of days. And so today we are going to further dissect the day as a unit that one can manage and manage extremely well, and, in fact, can optimize. So we're basically going to talk about how to leverage science-based protocols. And when I say science, I mean, quality, peer-reviewed science published in excellent journals. We're going to talk about how to take that science, convert it into specific protocols that break up along the course of a single day and direct certain types of behaviors in order to optimize the various features of life. I will couch this in the context of what I do across a daily 24-hour rhythm.
That doesn't mean that you have to follow this schedule at all or even in part. It's just by way of example. Any number of the different things that I describe could be applied to any number of different schedules or frameworks. But if there's one truth that applies to all of us, is that we all have to exist within the context of this 24 hour rhythm that we all possess. So that's what we'll focus on. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford.
It is, however, part of my desire and effort to bring zero cost to consumer information about science and science-related tools to the general public. In keeping with that theme, I'd like to thank the sponsors of today's podcast. Our first sponsor is ROKA. ROKA makes eyeglasses and sunglasses that I believe are the very highest quality possible.
Developed by two All-American swimmers from Stanford, ROKA sunglasses and eyeglasses were developed with their intention to create sunglasses and eyeglasses that could be worn anywhere. So while exercising or while working, at home, while driving. The reason I like ROKA glasses so much is that first of all, they're extremely lightweight. The optical clarity of the lenses is excellent, and so I often just forget that I have even have them on. When I'm outside and I'm wearing sunglasses, they have this really terrific feature which is that I can move in and out of shadows or the cloud cover can change and I can see perfectly well the entire time.
You know, many eyeglasses and sunglasses that I've tried, depending on what we call the "ambient lighting conditions," the local lighting conditions outside, I have to take them off or put them back on. It's really annoying for me. But with ROKA glasses, somehow, I'm assuming because they really understand the science of the visual system, the eyeglasses and sunglasses work seamlessly with whatever environment you're in. So that's absolutely terrific. Another thing about ROKA eyeglasses and sunglasses is that their aesthetic is really terrific.
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Again, if you're interested, you can go to helixsleep.com/huberman for up to $200 off and two free pillows. So let's talk about how to apply quality, peer-reviewed science to your day and how to optimize everything from sleep to learning, creativity, meal timing, et cetera.
As I mentioned earlier, I'm going to do this in the context of my day and what I typically do. However, the specific protocols for any number of different things, sleep, relaxation, meal timing, exercise, et cetera, any one or all of those could be rearranged to suit your specific needs. I'm going to tell you what I do from morning until waking and even what I do while I sleep in order to optimize my sleep.
So let's start with getting up in the morning. Now, for me, I tend to wake up sometime around 6:00 AM, 6:30, sometimes as late as 7:00 AM. I don't typically sleep much later than 7:00 AM. The first thing I do after I wake up is I take the pen that's on my nightstand and the pad of paper on my nightstand and I write down the time in which I woke up. Now, I do sleep with my phone in my room. I realized this is considered a sin and has certain hazards associated with it, but I put my phone on airplane mode about an hour before I go to sleep.
And then I set my alarm typically for 6:30 AM. And some days the alarm wakes me up; other days I wake up before the alarm. And yes, some days the alarm goes off and I hit snooze a few times, and then usually by 7:00 AM, I am up and out of bed. The reason for writing down what time I wake up is because I want to know that average wake up time.
That average wake up time informs what's called my "temperature minimum." It tells me when my body temperature was lowest. The temperature minimum is the time in each 24-hour cycle that your body temperature is lowest.
I don't sleep with a thermometer in my mouth or elsewhere, and I don't think you should either. Instead, I know that the lowest temperature that my body will be at across the 24-hour cycle tends to be two hours before my typical wake up time. And I want to know that number. It's called our "temperature minimum." So if you're somebody that typically wakes up at 8:00 AM, then your temperature minimum is sometime around 6:00 AM. Remember, the temperature minimum is a time in the 24-hour cycle.
I don't care what my actual temperature is; I care when my lowest temperature is. And I know that that lowest temperature is approximately two hours before my average wake-up time. So I highly recommend that you write down when you wake up or track that in some way that works for you and use that as a reference point to determine your temperature minimum. We will return to the temperature minimum and how you can leverage the temperature minimum for several things: shifting your clock, shifting your circadian sleep schedule and wake schedule. Also for shifting your eating schedule, et cetera, We will return to that.
But even if you don't travel, even if you don't care about things like jet lag, even if you sleep fabulously all year round, never have a poor night's sleep, knowing your temperature minimum, that time when your temperature is at its lowest point, is a valuable thing to know. The second thing I do after I wake up is to get into forward ambulation, which is just nerd speak for taking a walk. I have a dog, and as many of you know, he's a bulldog and he doesn't really like to walk, especially not in the morning.
But for humans and for animals, there's a phenomenon whereby when we generate our own forward motion, forward ambulation, visual images pass by us on our eyes, so-called "optic flow." And for those of you that are low vision or no vision, the same phenomenon occurs in the auditory system. Sounds pass by us in so-called "auditory flow." Getting into a mode of forward ambulation, and especially experiencing visual flow, has a powerful effect on the nervous system. The effect it has is essentially to quiet or reduce the amount of neural activity in this brain structure called the "amygdala." Amygdala means "almond," and many of you have probably heard about the amygdala for its role in anxiety and fear and threat detection.
And indeed, the amygdala is part of the network in the brain that generates feelings of fear and threat and anxiety. It does a bunch of other things too, but that's one of its primary functions. There are now at least half a dozen quality papers published in quality, peer-reviewed journals that show that forward ambulation, walking or biking or running, in generating optic flow in particular has this incredible property of lowering activity in the amygdala and thereby reducing levels of anxiety.
There are two papers that I'd like to highlight in particular that relate to this phenomenon. The first one was published in the journal Neuron and the title of this paper is "Whole-Brain Functional Ultrasound Imaging," that just means they have a cool technique to evaluate the activity of structures in the brain across the entire brain, reveals brain modules for visual motor integration. What they found in this study, and I should mention the first author is Mace, this comes from Botond Roska's group, this was work done in mice, but I'll talk about other species in a moment.
What they found was essentially that when these mice walk forward and their eyes move from side to side, which is a natural consequence of moving forward, so-called "optic flow" is flowing past their eyes, many brain areas are activated, increase in their level of firing, but the amygdala in particular reduced its levels of firing. That's a very interesting finding, but it is in mice. However, another paper, "Eye-Movement Intervention Enhances Extinction via Amygdala Deactivation," was published in The Journal of Neuroscience, a strong journal, and shows that, again, these eye movements, these lateral eye movements from side to side reduce activity levels in this fear/threat/anxiety center in the brain, the amygdala. Now, those are eye movements. They didn't specifically look at forward ambulation.
And yet other papers have looked at forward ambulation and we know that forward ambulation, walking forward, generates the sorts of eye movements that cause optic flow and reductions in amygdala activation. So for me, this process of taking a walk each morning isn't about exercise. It's not about burning calories. It's not about any of that. It's really about getting into optic flow and reducing the levels of amygdala activation.
Now, I don't have anxiety, at least I don't have chronic anxiety or generalized anxiety. I tend to have a lot of energy, but at these points in the morning, I'm not very energetic. Sometimes I'm sort of shuffling more than I'm walking in fact. And Costello is almost always shuffling and I'm almost always trying to drag him first thing in the morning. But that walk is a particularly important protocol each day because it really serves to push my neurology in the direction that I'd like it to go, which is alert, but not anxious.
And it's kind of a fine line sometimes, especially as events surface throughout the day, emails come in, text messages come in, get bombarded with a number of things. I want to be alert and responsive. I want to be able to focus, but I don't want to. feel anxious or reactive to these things. So the forward ambulation and this optic flow is the way that I ensure, based on quality, peer-reviewed data, that my amygdala activation is slightly suppressed. Now, at the same time, I also want the alertness.
I want alert and focused. I don't just want to be sleepy or super, super relaxed. I want to have a high degree of focus and alertness because I'm soon going to move into a about of work.
I need to lean into the day. So in order to do that, I make sure that the walking is done outdoors. That might be sort of a duh, but many people get up and start moving around their house, their apartment, and they don't go anywhere. And just walking around inside, it will generate some optic flow, but nothing like the sort of optic flow that you can generate in larger environments like out of doors environments. If you can't get outdoors, doing it indoors is perfectly fine, but it's not going to have the same magnitude of positive effect.
Now, in order to get the alertness, I do it outdoors because I also want sunlight in my eyes. I know many of you have heard me talk about this ad nauseam on various podcasts, in this podcast, but getting sunlight in your eyes first thing in the morning is absolutely vital to mental and physical health. It is perhaps the most important thing that any and all of us can and should do in order to promote metabolic well-being, promote the positive functioning of your hormone system, get your mental health steering in the right direction. There are a number of reasons for this, but before I get into those reasons, let me just emphasize what the protocol is.
The protocol is get outdoors, ideally with no sunglasses if you can do that safely, even if there's cloud cover. More photons, light information are coming through that cloud cover than would be coming from a very bright indoor bulb. So getting outdoors is absolutely key.
How long should you do this? It's going to depend on the brightness of the environment. It's going to depend on a number of different factors. Two minutes would be a minimum, 10 minutes would be even better, and if you can, 30 minutes would be fantastic.
Now, it's a very bright day or, you know, you live in a place where there's bright sunlight, clear day on a snowfield, you would only need something like 60 seconds. But most people aren't living in those sorts of conditions. So getting outside for a 10-minute walk or a 15-minute walk will basically ensure that you're getting adequate stimulation of these neurons in the eye that are called the "melanopsin," intrinsically photosensitive ganglion cells. I know that's a mouthful.
These are neurons that don't care about shapes of objects or the motion of objects. These are neurons that convey to the brain that it's daytime and it's time to be alert. And it sets in motion a huge number of biological cascades within every cell and organ of your body from your liver to your gut, to your heart, to your brain. It really sets things down the right path.
Early in the day, we experience a natural and healthy bump in a hormone called "cortisol." Cortisol comes from the amygdala. That cortisol, as I mentioned, is healthy and normal and promotes wakefulness.
It actually promotes a healthy immune system. So I know you've heard that stress and cortisol disrupt the immune system, but not the short little pulse of cortisol that you get each morning. It's very important that that pulse of cortisol arrive early in the day. I want to emphasize this again.
It's very important that that pulse of cortisol arrive early in the day And that pulse of cortisol is going to happen once every 24 hours no matter what. It's going to happen and you get to time it. How do you time it? Primarily by when you view bright sunlight or bright light of another kind, and we'll talk about that in a moment. So you want that cortisol pushed early. If you wake up before the sun comes out, it's fine to turn on artificial lights, but then you would want to get outside as soon as you can to get this, excuse me, natural light stimulation of your eyes. And it does have to be to your eyes.
Just to really drill down into the details for a moment, you don't want to stare directly at the sun or any light that's so bright that it feels painful. If you feel like you have to close your eyes or blink, please do. You don't want to damage your retinas.
The point here is to get the sunlight indirectly. It's going to essentially be scattered everywhere through the cloud cover, but you know from looking at us at a flashlight directly into that flashlight versus looking at the beam that flashlight generates on the ground that if you're standing in the shade, you're going to. get less of that sunlight than you are if you're out in an open field. So this is why the time outside, it's going to need to vary depending on your particular environment. But do your best to do this every day. If you miss a day, no big deal, but try not to miss more than one day.
Otherwise your mental and physical health will start to suffer. And doing this each day costs nothing. It's just time You can combine it with the forward ambulation with the walk and the optic flow that I talked about before. And that's what I do each morning to generate a sense of alertness in my body and brain to generate a sense of calm, yet alert.
And that's also what I do with Costello, with my bulldog. People have asked me, do the same mechanisms apply to animals? Well, the reality is many of these mechanisms were actually discovered in animals, and then were tested in humans and verified that they also exist in humans. Not always.
Sometimes it was the reverse, where they were tested first in humans, and then brought to animals. But indeed, your dog, your horse, you know, I don't know what other animals are out there, they need this. Now, if you have a hamster or a nocturnal animal, the reason why they like to run on their wheels at night is because they're nocturnal. They don't like being in the light. Light actually causes them to freeze, right? Actually, if you are into aquaria, you like fish, they always say, "Don't overfeed your fish.
You'll kill the fish." That's true, but guess what the fastest way to kill a fish is? To keep the lights on 24 hours a day They also need circadian rhythms, these 24-hour rhythms. So we'll do an entire month at some point about pet health, but meanwhile, get that morning sunlight. So now we have a first protocol, which is to write down the time of day that you wake up, the second protocol is to take a walk first thing in the morning, and the third protocol is woven in with that walk, at least for me, which is to get that sunlight exposure.
Now, if you can't get sunlight exposure, you absolutely can't, I don't necessarily recommend buying one of these dawn alarm lights. And I'm sorry to say this, but they're just vastly overpriced relative to what they are. They're basically a bright LED. I instead use, I have a pad that's a 930-lux LightPad. I think it was designed for drawing.
Those are available at a fraction of the cost that a morning light simulator would provide, and yet it's really bright enough, at least for me. I tend to put it on my desk while I work each morning. So here's a principle that you can leverage.
If you want to be alert, view bright lights and make those lights above you or in front of you. If you want to go to sleep soon or you don't want to be awake for whatever reason, try and eliminate your exposure to light. And this, again, is not about exposure of the skin to light; this is about exposure of your eyes, of your neural retinas to light. For those of you that are concerned about blue light, I want to that blue light is precisely the wavelength of light that is optimal for stimulating these neurons in your eye, which set your circadian rhythms properly.
So you don't want to shield yourself from blue light early in the day or throughout the day or anytime you want to be awake. In fact, that could have a number of detrimental consequences. Fortunately, all those consequences are going to be reversible after a short period of time of making sure that you don't wear your blue blockers during the day, please. The time to wear blue blockers, if you do, is at night and in the evening when you're headed towards sleep. My colleague Samer Hattar, who is head of the chronobiology unit at the National Institute of Mental Health, has spoken about this before on my Instagram. We held an Instagram Live and I said, "Samer, what do you think about blue blockers?" And he said, "I don't think that's a good idea at all, unless it's really late at night and you're in a bright environment and you're trying to limit the amount of bright light that impacts the eyes."
Eliminating specific wavelengths of light, in Samer's opinion and also in my opinion, is not a natural thing for the visual system and the brain to experience. Some people get headaches while they work on the computer all day or staring at screens, and so they get blue blockers thinking that's going to protect them from their headaches. However, any protection that you get from headaches from blue blockers is going to be minimal in comparison to what's really going on there, which is that people are viewing devices and screens up close for too many hours throughout the 24-hour cycle.
A better remedy would be to step away from that computer from time to time, and to make sure that you can look far off into the distance. Ideally, a distance longer than 20 feet like view a horizon, go out on a balcony, things of that sort. Take a walk around, get into optic flow So if you're into blue blockers, make sure you're only wearing them in the late evening and at night.
I personally don't wear blue blockers at all. I prefer to just control my light viewing behavior by doing this, I do the other form of circadian control, which is to dim the lights. And I do that because dimming the lights and setting them lower in the environment sets up the brain and body for sleep much better than simply just wearing some blue light blue blockers, excuse me. And please know if you do wear blue blockers that if the light in your environment is bright enough, it doesn't matter if you're blocking out the blues. The cells in the eye will respond to other wavelengths of light.
So I have no vendetta against the blue blockers, and, you know, I fully expect the blue block-anistas to come after me with, I guess, blue blockers, but as you do that, please understand that the biology points in the direction of get a lot of bright light throughout the day, including blue light, and at night, just limit the total amount of overall light that you're exposed to, including from screens. So then Costello and I get back from our walk. Sometimes that walk was 10 minutes, sometimes it was 60 minutes, depending on how slowly Costello is walking that day. Indeed, many mornings I'm the guy carrying his bulldog back up the hill. My neighbors know me so well, they know Costello so well that they've since stopped pulling over and asking if the dog is okay.
Sometimes they'll ask if I'm okay. Nonetheless, we get back, I give him his food, I give him his water, and I give me my water. I'm a big believer, based on quality, peer-reviewed data, that hydration is essential for mental performance. Now, I confess I don't really like drinking big glasses or big jugs of water first thing in the morning.
I don't know why, but my thirst doesn't tend to kick in first thing. You may be different. Either way, I force myself, essentially, to drink at least 16 and, most days, 32 ounces of water. I also put a little bit of sea salt in the water.
As many of you know, neurons require ionic flow. What that means is neurons need sodium, they need magnesium, and they need potassium in order to function. We do tend to get dehydrated at night. Even if the day is not very hot, I try and top off or I try and make sure that I'm hydrated early in the day before I begin any work.
So I make myself drink this water with a little bit of sea salt. How much sea salt? If you really want to get detailed, I suppose it's about half a teaspoon. It's not much, That's what I do. And I drink that more or less room temperature.
I find that drinking really cold water first thing in the day kind of like cramps up my insides, so I don't do that. At that point, I start thinking about and fantasizing about and craving caffeine, but I don't drink that caffeine yet. I purposely delay my caffeine intake to 90 minutes to 120 minutes after I wake up. Of course, I know when I wake up 'cause I wrote it down, although it's pretty easy to commit to memory.
The reason I delay caffeine is because one of the factors that induces a sense of sleepiness is the buildup of adenosine or, as some people call it, adenosine in our system. The buildup of adenosine accumulates the longer we are awake. So when I wake up in the morning, when you wake up in the morning, your adenosine levels are likely to be very low. However, caffeine is an adenosine blocker.
It's actually a competitive antagonist for you aficionados. It sort of parks in the receptor that adenosine normally would park at and prevents adenosine from acting on that receptor. That's why you feel more alert, because it's essentially blocking the effect of this sleepiness factor that we all create called the "adenosine." The reason for delaying caffeine intake 90 minutes to two hours after waking is I want to make sure that I don't have a late afternoon or even early afternoon crash from caffeine. One of the best ways to ensure a caffeine crash is to drink a bunch of caffeine, block all those adenosine receptors, and then by early or late afternoon, when that caffeine starts to wear off and gets dislodged from the receptors, a lower level of adenosine is able to create a greater level of sleepiness.
It took me years to figure this out. I used to wake up and I'd think, "Oh, I don't want to drink caffeine too close to bedtime, so I'm going to start drinking my caffeine really early." I let my cortisol naturally come up in the morning. I avoid drinking caffeine until about 90 minutes or two hours after waking.
And when I do that, I find that I don't experience the afternoon crash. At least I don't experience that crash unless I do something foolish, like ingest far too much food at lunch or I stay up all night the night before. But provided I don't do anything foolish like that, delaying caffeine to 90 minutes to two hours optimizes this relationship between adenosine and wakefulness and sleepiness in a way that really provides a nice, consistent arc of energy throughout the day and brings energy down as I'm headed toward sleep and falling asleep. My primary objective early in the day is to get into a mode of being focused, yet alert so that I can get work done.
I found that the best way for me to achieve that state is through fasting. So I don't eat anything until about 11:00 AM or 12:00 noon. I'm not absolutely religious about it. There are days when I'll have a few Brazil nuts or a spoonful or three of almond butter, for instance, but most days I'm not doing that. I'm just not eating anything.
I'm drinking some caffeine caffeine source for me is yerba mate, guayusa tea. Those are my preferred sources I tend to avoid coffee these days. Occasionally I'll have a cup, but most often I stick to the teas. I drink water as much as I feel I need to and want to.
And I also drink my athletic greens, which is compatible at least for me with fasting. Let's talk about why fasting works to create this heightened state of alertness, yet calm brain state. Fasting increases levels of adrenaline, also called "epinephrin" in the brain and body. And when our levels of epinephrin and adrenaline are increased, we learn better, we can focus better.
There's terrific data supporting that. You don't want epinephrine, aka adrenaline, too high. That feels like stress and panic. You get jittery, you can't focus. But in its optimal range, adrenaline really provides a heightened sense of focus and the ability to encode, meaning bring in, and retain, remember information.
And so since my job is mainly a cerebral one where I'm writing grants and working on papers, et cetera, I fast in the early part of the day. I mentioned ingesting things like guayusa or yerba mate or, in my case, athletic greens. Many people ask, in fact there's a whole community and discussion boards, et cetera, and YouTube comments on the internet, about what breaks a fast and what doesn't.
The fact of the matter is that's going to be highly individual because it's going to depend on how sensitive your blood sugar. And more accurately, it's going to depend on things like your insulin sensitivity. So for instance, if you're somebody who gets up in the morning, hydrates, and goes out for a six-mile run, you could probably eat a jar of almond butter and still be what's called fat-fasted. Your insulin levels will still be very low because even though that is a large volume of almond butter, even to me and Costello, that large number of calories comes from a source that doesn't increase blood sugar very much and insulin very much. Now, I'm not suggesting you do that, but what I just described as a vastly different situation than somebody that ate their last meal at 2:00 AM, and that meal was essentially a feast.
And for that person, fasting until 10:00 or 11:00 AM, their blood sugar might still actually be pretty high or even lowish such that they might eat one almond and it would bump them out of fasting. So you get the idea. It's going to depend on your recent eating history, your blood sugar history, your glycogen stores, et cetera. So if anyone tells you that breaks a fast or that doesn't, that's kind of silly.
Would one grain of sugar break your fast? No. Would an entire tablespoon of sugar break your fast? Yes. You'll get a big blip in blood sugar and insulin from that. However, how long that lasts, how long it breaks your fast will depend on how glycogen-depleted you are and a number of other factors.
So for me, I just keep it fairly simple: I ingest water, caffeine from your yerba mate and guayusa, and I drink my athletic greens with some lemon juice in it. That constitutes my fasting. And there are days when I do all those things.
There are days when I do none of those things. Although most days, I would say about 355 days out of the year, I'm ingesting water, caffeine, and athletic greens during this period of fasting early in the day, and that's the period of time when I do my work. One interesting fact about yerba mate and guayusa teas is that they increase release of something called "GLP-1." GLP-1 is related to glucagon. Glucagon is a hormone that you can sort of think about as opposite to insulin and blood sugar.
It's more complex than that, but GLP-1 has a couple of positive properties. One is it increases lipolysis and mobilization of body fat stores, so burning of fat. In fact, there are now a number of clinical trials that are achieving good success and there are drugs out there only available by prescription which mimic GLP-1 and are being used to treat, quite successfully, certain types of diabetes and obesity.
Now, I'm not diabetic, nor am I trying to shed a ton of body fat, but I figure as long as I'm fasting and as long as I like yerba mate and guayusa, which I do, they're delicious, I'll tell you which type I use in a moment, I might as well increase my GLP-1 because it's probably not as good as getting out and doing some cardio work. But nonetheless, if I'm fasted, increasing GLP-1 in my system, I'm going to be alert from the caffeine, the adrenaline, et cetera, and I'm going to burning body fat while I'm doing my work. So for me, it's just an efficient, biochemically rational, or I should say grounded in quality biochemistry sort of approach.
Yerba mate comes in a lot of different forms. There are a lot of different brands out there, et cetera. I don't have any relationship whatsoever in a business sense to any of these brands. Some of them are very smoky. I, just because of something in my genetic makeup, or I don't know, maybe it was some sort of Y chromosome-associated lesion early in life, but I don't like smoky flavors.
So I'm not a Gouda cheese guy. I don't like smoky stuff. You may love it, but I tend to avoid smoky-tasting mates.
Instead, there's a particular brand that I just found on the internet called Anna Park. I don't know Anna, I don't know if she has a park, and I certainly don't know what Anna Park is, but for me, that's the best-tasting yerba mate. Again, I don't have any relationship to them, but it's affordable in the context of yerba mate and it's the one that I use. And I should mention along the lines of affordability and GLP-1 is there's a nice feature of yerba mate which is if you put it in a filter or a metal strainer and you pour hot water over it, and then drink it, keep the leaves. The yerba mate leaves can be used over and over again.
It seems that the GLP-1 stimulating aspects of yerba mate actually are enhanced with subsequent pour overs. So there's something interesting about these teas that my tea aficionado friends tell me allows the tea to release more of some of the beneficial compounds by reusing the tea leaves. Now, eventually it'll grow mold and other sorts of disgusting things. You don't really want to run that experiment. I would say you can use it for a day or two before it starts to go bad, but that's a feature that will extend the life of whatever yerba mate you happen to use if you decide to use it, and that's certainly what I do. Next, I want to talk about what I'm doing while I'm drinking all this yerba mate.
'Cause I'm not just sitting there thinking about all the GLP-1 circulating in my system. I'm working. A couple of things for optimizing workspace that are grounded in neuroscience and physiology. I've talked before about the fact that when our eyes are directed upward, literally when our eyelids are open, no surprise there, and when our eyes are directed upward, it creates a state of heightened alertness.
And this has a relationship to the brainstem neurons that create alertness and their control over the muscles of the eye and, believe it or not, the eyelids. Now, it's not the case that if you are absolutely exhausted and you need to feel more alert that looking upward is going to make you feel wide awake, although it will help support your levels of alertness. The point here is that you can optimize your workstation in a physical way that leverages this aspect of the visual system and your level of alertness. Since most of us want to be awake while we're working, try and position your screen or your tablet, whatever device you happen to be working on, at least at eye level and ideally slightly higher. Now, if you think about it, most people are not doing this.
Most people are looking down at their computer or tablet or are angling their eyes at their screen at about 30 degrees. That is not going to support heightened states of alertness and optimal attention. In fact, the opposite relationship between eye position and alertness is also true. When we look down, when our eyelids are slightly closed, it tends to decrease our levels of alertness and increase our levels of sleepiness. I really want to emphasize this, that there's a bi-directional or reciprocal relationship between the brainstem areas that control alertness and the eyes, meaning how alert you are controls how open or closed your eyes are, no surprise there, but also the how open and upward directed your eyes are will increase your levels of alertness And if your eyes are pointed downward and your eyelids are hooded, like they're slowly closing, like Costello's are always are, you'll feel more sleepy, especially if you're somebody who tends to have that mid-morning sleepiness or mid-morning crash. So what I do is I have a standing desk, but I also prop the computer up such that it's at least at eye level.
And I haven't figured out yet how to develop a workstation where the computer is above me. I think the only way to really do that is actually to tilt one's body back, but actually that's not a good idea either. They have done studies recording from areas of the brain associated with alertness. Areas like locus coeruleus in the so-called reticular activating system. What they found is that depending on how reclined you are or upright you are, you will decrease with reclining and increase with sitting forward your levels of alertness. So body posture and whether or not your upright or reclining will impact your levels of alertness in the predictable ways.
And where you position your eyes, whether or not your eyes are upright, so to speak, looking up or directly forward or looking down, will dictate whether or not you are feeling more alert or more sleepy, respectively. So try and arrange a workstation or a position of your body in your chair or your standing desk, whatever it is, that allows you to work with a heightened state of alertness. This is really, really key for me because I found that when I would sit down, not only would my hip flexors start to get sore, I feel tight in the back, et cetera, but if I was staring down at my screen all day or even for short periods of the day, I would start to feel sleepy and I couldn't figure out what was going on. I also thought maybe I needed glasses.
I do wear readers at night, but it was really a problem. And simply by getting the screen directly in front of me at eye level, it's been completely transformative. So we're now at the description of my day in these protocols in which I would do a 90-minute about of work. Now, why 90 minutes? Well, the brain is going through these 90 minutes so-called "ultradian cycles" throughout the entire day and night. Every 90 minutes, we shift over from being very alert to being less alert, and then back to alert again.
Here's how it works. At the start of one of these 90 minute ultradian cycles, my brain is not quite engaged in whatever it is I'm trying to do. Oftentimes I have things jumping into my mind, I've got distractions, et cetera. I'll talk about how to deal with those distractions in a moment. But I set a timer for 90 minutes and I try and get a strong about of work done inside of that 90 minutes with the full understanding that the entire 90 minutes is not going to be uniform in terms of my ability to focus. There will be kind of peaks and valleys within that, but that 90 minutes is about what the brain can handle in terms of a dedicated effort for high degree of focus.
Some people can push out a little bit further, some people can't handle more than 10 minutes, but that's what I'm striving toward. You'd be amazed how much you can get done in 90 minutes if you are focused. So how do you increase that focus and how do you use the timer feature? Well, you can combine those. I use a program called Freedom. It shuts me out of the internet completely. So that means no checking the markets, no checking social media, no checking, you know, the news, no checking email, none of that.
I get a dedicated about of work done. I confess, I don't allow myself to go to the restroom in that period of time. Here's an interesting little tip that's grounded in physiology.
You have a direct neural connection from your bladder to your brainstem areas that increase alertness. This is why when you have to go to the bathroom, when you have to urinate, it is extremely agitating, right? It can be very, very agitating. I'm not encouraging you to get so agitated by filling your bladder so much and resisting going to the bathroom that you are uncomfortable and can't focus, but I generally will just drink liquids and work away and work away, and I won't walk away to go use the bathroom unless I absolutely have to. Sort of odd that we're talking about this, but this is one way in which I've learned to funnel my attention into whatever it is I'm doing.
Because as you all know, the moment you sit down to do some serious work and you flip off the internet, all of a sudden it's as if the phone has a voice, it starts calling you.. It's almost as if the restroom has a voice. But we all are familiar with the fact that if we are focused on something that all that just kind of melts away. So the goal is to get into what I call the tunnel, to really get into a tunnel of quality work. The brain loves that state, but it's very hard for many of us to access.
My phone is absolutely off. It's not on airplane mode. It's absolutely off during this time. If I've been struggling with that and, I confess, you know, there are times when, for whatever reason, something going on in life, it's been harder to put away the phone. I will sometimes put it in my car. I used to joke that I used to throw it up on the roof or something like that.
Look, I've done and I suggest people do whatever they need to in order to self-regulate that activity. And if you're somebody that feels that you absolutely need to be on your phone and on the computer for this work about or the work that you do, well, that's a different matter altogether. This is just simply how I work. So I will do 90 minutes and I do set a timer and I turn on the program, Freedom locks me out of the internet.
If someone rings the doorbell, I will often shout, "Not coming to the doorbell. Leave it there." I mean, unless there's a real emergency, I'm not going to step away from that work. I learned how to do this when I was a graduate student under different conditions where I used to slice brains on what's called a microtome. So I used to spend time, just cutting very thin slices, it's like a deli slicer, but for a brain, of various types of brains. And I've sectioned through a lot of brains. And we had a rule, which is that when the blade hits the brain, you don't stop pulling, even though it's very, very slow even if a nuclear bomb goes off, even if a fire alarm goes off.
Now, I don't want anyone, you know, burning to a crisp because they didn't step away from their workflow. That would be foolish, but that's the mentality that I've embedded in myself, that there's nothing more important than what I'm doing in that 90-minute block. And that's what works for me.
You can try various other things. That's what works for me. In addition, I use low level white noise.
This is something that is supported by quality, peer-reviewed data. We covered this on the episode on hearing and balance, but it turns out that white noise, which is essentially all frequencies of sound, or all frequencies of sound that we can perceive, mixed up kind of randomly, there's no structure to it, turned on at a low volume, not with headphones most of the time, puts the brain into a state that's optimal for learning and workflow. And I covered two papers during that episode.
One that showed that, indeed, brain areas involved in attention, brain areas involved in focus and cognition and memory, those are engaged to a greater degree when there is low levels of white noise playing in the background. The other paper that's really interesting did brain imaging and showed the areas of the brain that are associated with dopamine release are increased by low levels of white noise. Dopamine release is associated not just with pleasure, but with motivation and craving. So everything about this 90-minute block from the low levels of white noise to the position of my computer, how I'm standing, where my eyes are positioned, is geared towards putting me in this tunnel of work.
And I have to say that while it can be a challenge to try and achieve this state in this tunnel of work some days, you start to get kind of addicted to it. It feels really good. It's like a workout for the mind. And it is something that as you exit that 90 minutes, you really feel like you've accomplished a lot because often you have, and it just feels deeply satisfying. And I'm convinced that that's because of the release of neuromodulators like dopamine and the norepinephrine that's circulating in your system. And I want to be clear that I'm not perfect about this 90 minutes.
Occasionally I get drawn away. Occasionally something will happen or I'll go use the restroom or Costello will have a need or somebody will have a need that I will have to respond to, but I really try and achieve this most, if not every day that I'm alive because for me, that work session is kind of holy. It's where I set up a relationship, not just between me and the work that I'm doing, but between me and my ability to control my own state of mind using these various supports of the white noise, et cetera. But really those supports are peripheral to the fact that I'm creating this space.
I'm funneling my brain into a state rather than allowing whatever events and contexts on social media and elsewhere might be occurring in the world that would yank me out of what for me is my purpose and my mission in life, which is to do the sorts of work that I do. There's a powerful way in which you can place the timing of this 90-minute work about in an optimal way. You have access to a very important piece of data that dictates when this about should start more or less and when it should end. That piece of data is your temperature minimum.
If you're somebody who wakes up on average at 7:00 AM, well, then your temperature minimum is 5:00 AM. And you can be reasonably sure, I want to underscore reasonably, but you can be reasonably sure that your best work is going to be done anywhere from four to six hours after your temperature minimum. So for me, I tend to wake up around 6:30 AM, that means my temperature minimum is at 4:30 AM. You can add five hours to that. So that means that a 90 minute work about could fall at 9:30 AM and it would be fairly optimized. Or I could do it at 10:30 AM, or I could do it at 8:30 AM.
Somewhere in there, all right? That we can't say that it's exactly six hours after your temperature minimum. You will find it, however. There is a precise and best time for you to do this 90-minute work about. Whether or not it's five or six hours after your temperature minimum is going to vary from person to person. How do I know this? How do I know this relationship between temperature minimum and focus cognition? Well, temperature minimum defines the trough, the nadir, as they say, of your temperature across the 24-hour cycle.
And immediately after that, your temperature will start to rise. That temperature rise is actually what triggers the initial cortisol release that you experience and wakes you up further. And then, of course, that sunlight that you're getting is going to further enhance that healthy release of cortisol. That cortisol will then provide fuel, if you will, for that increase in temperature. And your body will continue to increase in temperature throughout the day toward the afternoon.
What you're trying to do in this idea of optimizing this 90-minute work about to a particular time of day is catch the portion of the steepest slope of that temperature rise. Now, again, you're not walking around with a thermocouple or a thermometer in some orifice of your body. So you don't have accurate information about temperature, but you can make very good guesses about when your body temperature is rising fastest by virtue of that temperature minimum. So again, just to be clear, it's a 90-minute work about. That's about what the brain can handle for a very intense work about.
Do you understand, again, that they're going to be portions of that 90 minute that your brain is flickering in and out of focus, other portions, where you're going to be entirely focused. That's entirely normal. But when to place that 90-minute work about, when to start it, and when to end it will depend on that temperature minimum. So if you're somebody who wakes up at 8:00 AM each morning, your temperature minimum is 6:00 AM, chances are you're going to want to start this work about somewhere around 10:00 AM or 11:00 AM. Now, some people wake up and feel very alert first thing in the morning. They can really do their best work first thing in the morning.
Please, if that's you continue to do that. Leverage that time. Use that time. But if you're somebody who struggles to find focus, definitely let your physiology and this rise in your body temperature support your efforts to focus rather than trying to do your best work at times of day when your physiology is actually directing your body and your brain toward de-focus and towards being more lethargic. It just is setting yourself up for success when you try and capture this rising phase of your temperature. So up until now, we've been emphasizing practices that allow you to optimize your level of alertness and your levels of mental focus.
Data going back to the 1990s supports the idea that physical movement of particular kinds can support brain health and brain function both in the immediate term and in the long term. Now, this is has had a profound impact on the field of neuroscience, but frankly, it's also had a profound impact on how I structure my day. So after I've finished a about of work, this 90-minute about of work, I force myself some days, other days I want to, but I force myself to do some sort of physical exercise that is going to be supportive of my brain health and brain function and organ health and bodily function in general.
So I just briefly want to touch on what the structure of that exercise looks like, how it's structured within the day and how it's structured across the weeks in fact, based on the scientific data and what the scientific data say is best or optimal in order to promote longevity of the brain, ability to focus, as well as cardiovascular health and all the other things that we know exercise supports. Now, there are various forms of physical activity or what we call exercise, but those can generally be batched into two categories. First is strength and hypertrophy work.
So physical movements that are designed to make you stronger and/or make your muscles larger. There's also endurance work. Physical exercise and movements that are designed to allow you to do more work over time or to extend the amount of time that you can do work of any kind, both physical and mental.
And we did two full podcast episodes on the details and the science and the protocols related to these topics. We did an episode on the science of strength and hypertrophy, of building strength and muscle building. And that included a lot of protocols.
And we did an episode on endurance. How to build any one or all of the four types of endurance, which are muscular endurance, anaerobic, aerobic, long-distance endurance, et cetera. So if you're interested in the specifics of those protocols, please see those episodes. However, right now I just want to emphasize how the data impact my day and how I structure my day in a way that I can incorporate physical movement in a way that supports my brain and health.
Basically, after I finished that cognitive work about, that 90-minute work about, I do some form of physical exercise for about an hour. The data all point to the fact that working out hard for longer than an hour can actually be detrimental because of the way that it raises cortisol. And cortisol can be a good thing if it's appropriately timed and in the appropriate low levels, but you don't want to have your cortisol levels up throughout the day or have big spikes of cortisol repeatedly. So keeping workouts relatively short can definitely help with that And certainly if you're training hard, 60 minutes or less should be more than sufficient. And for many people, including myself, 45 minutes or 50 minutes is probably even more optimal. The basic design of this physical exercise is that it be approximately 60 minutes.
So maybe 60 plus or minus 15 minutes should be well within the margins of keeping hormonal health proper and not going too long nor making the workout so short that it's not beneficial. And essentially what the data tell us is that in order to optimize cardiovascular and brain health and other systems of the body, we want to exercise at least five days per week. I know that seems like a lot.
It certainly is a lot for certain people. Some of you, you compulsive exercisers, might gasp at the idea of taking two days off. I personally find that taking two full days off per week is actually both beneficial to my exercise training performance, as well as pleasant. I like those rest days. But essentially the structure of the exercise regimen that works for sake of supporting health is going to be one in which there's a 3:2 ratio.
Where for a 12-week period or so, maybe 10 to 12 weeks, three of those five workouts per week emphasize strength and hypertrophy and the other two emphasize endurance. Then, after 10 or 12 weeks, one over to a 10- or 12-week regimen of doing a 3:2 ratio where you're prioritizing endurance work. So primarily the sorts of workouts that are described in the endurance episode and those protocols. And the other two days, you're focusing on strength and hypertrophy work merely to maintain strength and hypertrophy, to not lose the strength and hypertrophy that you've created. And there a lot of data now supporting the fact that maintaining muscular health and bone health is supported by resistance training, weight training of various kinds.
It can also be done with body weight if you don't have access to equipment. And, of course, that doing cardiovascular endurance work is very beneficial both to the muscles of the body, the organs of the body, but also to the brain. Many of you have probably heard that doing physical exercise of various kinds can support the production of new neurons in the brain.
Frankly, those data are specific to research animals. As far as we know, increases in neuron number are not supported by exercise in humans. There is a little bit of data that supports that maybe a few neurons might get created by running or weightlifting or things of that sort in human beings, but there's still a host of other reasons to have this hour or so per day where one is doing physical exercise. And those include increased blood flow to the brain. Remember, the brain is an organ too. It's the most metabolically demanding organ in your body and it's receiving those metabolic factors, it's receiving its fuels by way of vasculature, of blood vessels and capillaries and veins and things of that sort.
So movement is very crucial to get your brain to function properly. Movement of various kinds is very important to get your brain to function properly. Resistance training turns out to be as important as endurance training because of the way that it stimulates the release of particular hormones actually from bones, things like osteocalcin, which can positively impact brain function and can support the health of existing neurons as opposed to increasing the number of neurons. It turns out increasing the number of neurons may not actually be as beneficial as we think. It all sounds great. More neurons, more neurons.
Certainly more neurons is better than fewer neurons and losing neurons, but incorporating new neurons into existing brain circuitry is actually very challenging for the brain to do. I make sure that after that workout, I get this one hour or so of exercise five days per week because of the ways that it supports my general health. And there are now hundreds of studies supporting the fact that both endurance work and strength training or hypertrophy training done in combination, meaning not necessarily in the same workout, but done across the week is immensely beneficial for the production of things like brain-derived neurotrophic factor, for limiting inflammatory cytokines like IL-6, for promoting anti-inflammatory cytokines like IL-10, provided that exercise is of the proper duration and that it's not so intense that you're actually creating damage to the various systems of the body. Now, where is the threshold between optimal, sub-threshold and detrimental? This is a complicated theme if we don't put some structure around it.
So let's put a little bit of structure around it. We already said that about 60 minutes, so 60 minutes plus or minus 15 minutes, is going to be optimal for all these health benefits. What about the structure of the actual workouts? Well, we need to address this issue of intensity.
A good rule of thumb based on the literature, and I discussed this with Dr. Andy Galpin prior to this strength and hypertrophy and endurance episodes, and the literature that's published in quality, peer-reviewed journals really points to the fact that approximately 80% of the resistance training you do should be resistance training that doesn't go to what they call failure, where you can't actually move the resistance anymore. The other 20% can be of the higher intensity to failure type training.
Now, with respect to endurance work, one can build up endurance without having to log long, long mileage or extensive mileage in the pool or by running. And that's because there are these other forms of endurance that can build up, for instance, the capillary beds within the muscles. Building up the capillary beds within the muscles will allow more oxygen utilization within the muscles, and thereby will increase your endurance both of the muscles, but also will improve brain metabolism and the way that the heart functions, so cardiovascular function.
That 80/20 rule of less than failure and work to failure in the resistance exercise regime can be transported or translated to the endurance exercise portion by focusing on that thing that we're familiar with, which is the burn when we're running hard or cycling hard, we'll experience a kind of burning of the muscles that's associated with the lactate system. During the episode on endurance, I pointed out that that burn is not lactic acid. Contrary to common belief, it is not lactic acid.
It's associated with lactate metabolism. And again, about 80% of the endurance work should not incorporate that so-called "burn," but if 20% of that work or so, I should say approximately 20% of that work, does include the so-called "bu