Huberman Lab - How To Build Endurance In Your Brain & Body

Welcome to the Huberman Lab Podcast,

where we discuss science

and science-based tools for everyday life.

I’m Andrew Huberman,

and I’m a professor of neurobiology and ophthalmology

at Stanford School of Medicine.

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 Athletic Greens.

Athletic Greens is an all-in-one

vitamin mineral probiotic drink.

I’ve been taking Athletic Greens since 2012,

so I’m delighted that they’re sponsoring the podcast.

The reason I started taking Athletic Greens

and the reason I still take Athletic Greens

once or twice a day

is that it helps me cover

all of my basic nutritional needs.

It makes up for any deficiencies that I might have.

In addition, it has probiotics,

which are vital for microbiome health.

I’ve done a couple of episodes now

on the so-called gut microbiome

and the ways in which the microbiome interacts

with your immune system,

with your brain to regulate mood,

and essentially with every biological system

relevant to health throughout your brain and body.

With Athletic Greens, I get the vitamins I need,

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and the probiotics to support my microbiome.

If you’d like to try Athletic Greens,

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There are a ton of data now

showing that vitamin D3 is essential

for various aspects of our brain and body health.

Even if we’re getting a lot of sunshine,

many of us are still deficient in vitamin D3.

And K2 is also important

because it regulates things like cardiovascular function,

calcium in the body, and so on.

Again, go to slash Huberman

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Today’s episode is also brought to us by Element.

Element is an electrolyte drink

that has everything you need and nothing you don’t.

That means the exact ratios of electrolytes are an element,

and those are sodium, magnesium, and potassium,

but it has no sugar.

I’ve talked many times before on this podcast

about the key role of hydration and electrolytes

for nerve cell function, neuron function,

as well as the function of all the cells

and all the tissues and organ systems of the body.

If we have sodium, magnesium, and potassium

present in the proper ratios,

all of those cells function properly,

and all our bodily systems can be optimized.

If the electrolytes are not present,

and if hydration is low,

we simply can’t think as well as we would otherwise,

our mood is off, hormone systems go off,

our ability to get into physical action,

to engage in endurance and strength,

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They’re all delicious.

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Today’s episode is also brought to us by Thesis.

Thesis makes what are called nootropics,

which means smart drugs.

Now, to be honest, I am not a fan of the term nootropics.

I don’t believe in smart drugs in the sense that

I don’t believe that there’s any one substance

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I do believe based on science, however,

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I’m pleased to announce that the Huberman Lab Podcast

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We partnered with Momentus for several important reasons.

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Second of all, and perhaps most important,

the quality of their supplements is second to none,

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There you’ll see those supplements,

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Again, that’s slash Huberman.

For the last month, four episodes to be exact,

we’ve been discussing physical performance

and skill learning.

We’ve talked about how to learn skills faster,

whether or not those are skills for athletic performance,

dance, music, things of that sort.

We’ve also talked about how to gain strength

and how to lose fat faster by leveraging the nervous system,

things like shiver and non-shiver,

non-exercise activity-induced thermogenesis.

We talked about how neurons

can actually trigger accelerated fat loss.

We talked about hypertrophy, also called muscle growth,

and we covered everything from sets and reps, protocols,

how long to stay in a cold ice bath, when to get out,

how to keep shivering.

We’ve covered a lot of tools and a lot of science.

So if you’re interested in those things

and you even perhaps want to learn a little bit

about how we make energy, ATP,

from carbohydrates or from fats,

it’s all covered in the previous four episodes.

This was going to be the time

that we move to a new topic entirely,

but we are going to do one more episode

in this series on physical performance

for the simple reason that you asked many questions

about something that’s vitally important,

both for physical performance

and long-term and short-term health, and that’s endurance.

And so today we are going to talk about endurance.

Now, if you’re a strength athlete

or you’re not interested in endurance,

don’t depart just yet because it turns out

that there are ways to train endurance

that are very different

than I would have previously imagined.

If you only think about long runs, long swims,

marathons, half marathons, 10Ks, 5Ks,

and that sort of thing puts you to sleep,

kind of like Costello is snoring

in the background right now,

he’s not a long distance endurance athlete, that’s for sure.

If you’re interested in those things

or if you are averse to those things,

I encourage you to continue listening

because we are going to talk about a little bit of science

and then some specific protocols

that really define what endurance is,

the four types of endurance,

and ways to train those in concert

with the other things that you might be doing,

like weight training or skill training or yoga.

And if you are an endurance athlete,

we are going to cover a lot of tools and science

that I’m certain will also help enhance your training

and performance in races or even just recreationally.

The topic of endurance, I think,

has been badly misrepresented, frankly, online.

And when you start digging into the science

and you start talking to real experts in this area,

what you discover, what I’ve discovered,

is that it’s an incredibly interesting area

because it teaches us so much

about how our body and our brain use fuels

and how we can control which fuels

are used by our body and brain.

So today we will talk about the four kinds of endurance.

We will also cover the topic of hydration,

which might sound incredibly boring,

like, okay, just drink more water.

But it’s really interesting

because not only is hydration

a limiting factor on performance,

but there is a right way to hydrate

and there is a wrong way to hydrate.

There actually is a formula that I’ll teach you

to know how much water to be drinking,

depending on your activity levels.

And if that sounds like a simple thing,

like, oh, just tap off water until your urine runs clear,

that’s actually the wrong advice.

It turns out that if you don’t hydrate properly,

you can see 20 to 30% reductions in performance,

whether or not that’s strength,

whether or not that’s increasing hypertrophy,

whether or not that’s running, swimming,

even mental performance.

So even if you’re not an athlete

or a recreational athlete at all,

I encourage you to stay tuned for the part about hydration.

So we’re going to cover, as usual, a little bit of science,

and then we’re going to dive right into protocols

that you can apply if you like,

and if you deem those correct and safe for you.

Before we dive into all that,

I want to make an important announcement,

which is all the episodes of the Huberman Lab podcast

are now housed on a single website,

which is

If you go to,

you can find all the episodes in YouTube,

Apple, and Spotify format with links there.

The website is also searchable.

So if you go into the little search function,

which you’ll find very easily,

and you put in, for instance,

creatine or sleep or ice bath or sauna,

it will take you to the specific episodes

that contain that information.

And in addition, if you go to the website,, you have the opportunity to sign up

for what we call the Huberman Lab Neural Network.

The Huberman Lab Neural Network is a zero-cost resource

where once a month, perhaps more often,

you’ll receive a email newsletter,

and that newsletter will contain specific protocols,

announcements, attachments of PDFs,

and things of that sort of protocols, tools,

and science from the podcast.

We will also make any announcements about live lectures,

which at some point I’ll probably start doing

in various cities in the US

and probably around the world as well,

as well as other things that I think

would be really useful to you,

all of course at zero cost.

So that’s

Sign up for the Neural Network newsletter.

You can find that in the menu tab,

or it might pop up when you get there,

and I hope you will join.

And as a final announcement,

if you’re not already following us on Instagram,

you can go to Huberman Lab on Instagram.

And if you do that, I often make announcements

and release protocols and links to protocols

and things there as well.

I briefly want to touch on something

from the previous episode,

which is that if you are somebody

that is trying to increase muscle strength and or size,

or if you’re simply somebody

who doesn’t want to increase muscle strength and size,

you just want to maintain the musculature that you have,

it’s vital that you perform at least five sets

of resistance training per muscle per week.

If we don’t do that, we lose muscle over time.

And that is one reason among many

to have a regular resistance training protocol.

Nobody wants to start resembling a folded over envelope

or a melted candle.

No one wants to have challenges getting up out of a chair

or off the ground.

Maintaining musculature is vital,

not just to our immediate health,

but to our long-term health trajectory.

So I just want to emphasize that point.

If you’re curious about the sets, the reps,

how close to failure to go or not go,

whether or not you should be doing

your cardiovascular training before

or after your weight training,

all of that is in the previous episode,

right down to the details.

And I like to think it made simple for you to understand.

But I do strongly believe that resistance training,

whether or not it’s with body weight or bands or weights

or simply lifting rocks in the yard or logs in the yard,

is vital for our systemic physiology and our overall health.

And that includes our brain health.

And I described the reasons for that

and the mechanisms in the previous episode.

Today, I’d like to talk about endurance

and how to build endurance and how to use endurance

for the health of your entire body.

Endurance, as the name suggests,

is our ability to engage in continuous bouts of exercise

or continuous movement or continuous effort of any kind.

And I do believe that our ability to engage in activities

that we call endurance training

or physical endurance activities

do have carryover to mental performance

of things that require long-term effort.

I’ll touch on that at the end

and why there’s reason to believe

that there’s a biological crossover between those two things.

I don’t think it’s simply the case

that if you train yourself to be a strength

and speed athlete and to do short bouts of exercise

that are very intense,

that you can only do mental work

that’s of short bouts and very intense.

But it is clear that cardiovascular exercise,

exercise where you’re getting your heart rate up

continuously for a period of time,

and endurance exercise,

we will define what that is in a moment,

is vital for tapping into and enhancing various aspects

of our biology in the body and in the brain

such that our brain can perform work

for longer periods of time,

focused work, learning, et cetera.

So I want to dive into the topic of endurance

and I want to just begin by addressing something

that’s vital to any kind of effort,

whether or not it’s mental effort or physical effort.

So as always, a little bit of science

and we’ll get right into protocols.

So the key thing to understand

about energy production in the body,

meaning your ability to think, your ability to talk,

your ability to walk, your ability to run

is this thing that we call ATP.

ATP and mitochondria,

which are just little, what we call organelles within cells,

these little factories that make energy, if you will,

ATP is required for anything that requires energy,

for anything that you do that requires effort.

And there are different ways to get ATP.

And we have been gifted as a species

with the ability to convert lots of things into ATP.

We can convert carbohydrates,

literally the kinds of carbohydrates.

You eat a bagel, you eat a piece of pizza,

usually is dough and it has cheese and some other things.

Costello hears me talking about pizza.

Costello loves pizza, by the way.

Eating a piece of pizza,

it gets converted into various things,

fatty acids from the fats, glucose from the bread.

And those things get converted into ATP within cells

through things like glycolysis, things like lipolysis.

I talked about this in previous episodes.

So our muscles and our neurons

use different fuel sources to generate ATP.

The ones that are used first

for short bouts of intense activity

are things like phosphocreatine.

If you’ve only heard about creatine as a supplement,

well, phosphocreatine actually exists on our muscles.

And that’s why people take creatine.

You can load your muscles with more creatine.

And though, and excuse me,

phosphocreatine is great for short, intense bouts of effort.

So when you’re really pushing hard on something physical,

let’s say you see a car on the side of the road

and that car is stalled and a person says,

hey, can you help me push my car?

And you start to push,

it’s going to be phosphocreatine

is going to be your main fuel source.

Then you start to tap into things like glucose,

which is literally just carbohydrate.

It’s just sugar that’s in your blood.

And then if you keep pushing on that car,

you keep engaging in a particular effort

or you keep studying or you keep listening to this podcast,

you start to tap into other fuel sources

like glycogen from your liver,

it’s like a little pack,

just like you might’ve packed a sandwich

or something for work.

You have a little pack of glycogen in your liver

that you can rely on.

And you have fats stored in adipose tissue.

Even if you have very, very low body fat percentage,

like you’re one of these people

has like 3% or 5% body fat,

really thin skin, very little body fat.

You can extract lipids, fatty acids from that body fat.

It’s like a storage pack.

It is a storage pack for energy

that can be converted to ATP.

So without going into any more detail,

when I say today energy, or I say ATP,

just remember that regardless of your diet,

regardless of your nutritional plan,

your body has the capacity to use creatine, glucose,

glycogen, lipids.

And if you’re ketogenic, ketones,

we’ll talk about ketosis,

in order to generate fuel, energy.

Now, the other crucial point is that

in order to complete that process of taking these fuels

and converting them into energy,

most of the time you need oxygen.

You need air, basically, in your system.

Now it’s not actual air.

You need oxygen molecules in your system,

comes in through your mouth and your nose,

goes to your lungs and distributes via the bloodstream.

Oxygen is not a fuel,

but like a fire that has no oxygen,

you can’t actually burn the logs.

But when you blow a lot of oxygen onto a fire,

basically onto logs with a flame there,

then basically it will take fire, it will burn, okay?

Oxygen allows you to burn fuel.

So today we are going to ask the critical questions.

What allows us to perform?

What allows us to continue effort for long periods of time?

And that effort could be a run, it could be a swim,

it could be studying,

it could be anything that extends over a long period of time.

Well, you’re going to need energy

and you’re going to need oxygen.

But the way to answer a question,

like what allows us to endure, right?

Endurance, what allows us to keep going?

Well, we think of things like willpower,

but what’s willpower?

Willpower is neurons, it’s neurons in our brain.

We have this thing called the central governor,

which decides whether or not we should or could continue

or whether or not we should stop,

whether or not we should quit, okay?

So whether or not you’re somebody who has a lot

of what we would call resilience and endurance,

or whether or not you’re somebody who taps out early

and quits early or can’t handle frustration,

that has to do with your fuel utilization

in specific neurons.

So we have to ask the question,

what is the limiting factor on performance, right?

So instead of saying what allows us to endure,

we should say, what prevents us from enduring?

What prevents us from moving forward?

What are the factors that say, you know what?

No more, I’m not going to continue this run,

or you know what?

I’ve had a really long, hard day,

or maybe I’ve had an easy day, or I’m feeling lazy.

I just don’t even really feel like getting up and moving.

So what we’re going to talk about today

actually gets right down to the heart

of motivation and fuel use.

Motivation and fuel allocation.

And we are going to talk about specific training protocols

that you can follow that have carry over

between the bodily systems of running, swimming, et cetera,

and the way that your brain works.

So let’s talk about endurance by asking first,

what are the limiting factors on endurance?

What stops us?

Because in addressing that and answering that,

we will understand what allows us to get into effort

and to continue effort.

There are five main categories of things

that allow us to engage in effort.

And they are neurons, nerves, muscle, muscle,

blood, things in our blood, our heart, and our lungs.

Now, I don’t want to completely write off things

like the immune system and other systems of the body,

but nerve, muscle, blood, heart, and lungs

are the five that I want to focus on today,

because that’s where most of the data are.

As we go forward into this,

I want to acknowledge Dr. Andy Galpin,

who as with the last episode,

has been tremendously helpful and informative

in terms of the exercise physiology.

He is a true expert.

He has a laboratory.

He’s a full professor who does work on muscle biopsy,

who understands the science,

but who also works with athletes

and works with recreational athletes,

professional athletes,

really understands at a variety of levels

how all these systems work.

He’s the person I consulted with about today’s episode,

although I did access other literature as well.

And I’m going to mention a key review

for any of you aficionados

who really want to get down into the weeds.

But I encourage you, if you want more detail,

to check out Dr. Andy Galpin’s YouTube page.

I think he’s also on Twitter.

He’s definitely on Instagram.

His content is excellent, and he really understands.

I have learned, and I really believe,

that an intellectual is somebody who understands a topic

at multiple levels of specificity, of detail,

and can communicate that.

And Andy is a true intellectual

of muscle physiology and performance.

And if you hear the word intellectual

and you kind of back up and cringe from that,

understand that he’s also a practitioner.

So thank you, Andrew Galpin, Andy Galpin,

for your support in these episodes.

And we hope to have you as a guest on the podcast soon.

So nerve, muscle, blood, heart, and lungs.

Let’s talk about neurons and how they work, okay?

But I want to tell you about an experiment

that’s going to make it very clear

why quitting is a mental thing, not a physical thing.

So why do we quit?

Well, an experiment was done a couple of years ago

and was published in the journal Cell,

Cell Press Journal, excellent journal,

showing that there’s a class of neurons

in our brainstem, in the back of our brain,

that if they shut off, we quit.

Now, these neurons release epinephrine.

Epinephrine is adrenaline.

And anytime we are engaged in effort of any kind,

we are releasing epinephrine.

Anytime we’re awake, really,

we are releasing epinephrine into our brain.

In fact, this little group of neurons

in the back of our brain,

it’s called the locus coeruleus, if you like,

is churning out epinephrine all the time.

But if something stresses us out, it churns out more,

and then it acts as kind of an alertness signal

for the whole brain.

We also, of course, have adrenaline epinephrine

released in our body, which makes our body ready for things.

So think about epinephrine as a readiness signal.

And when we are engaged in effort,

this readiness signal is being churned into our brain.

When we’re relaxed and we’re falling asleep,

epinephrine levels are low.

Okay, so they did a really interesting experiment

where they had subjects engage in bouts of effort

of trying to move forward toward a goal,

but they manipulated the visual environment

with these stripes,

kind of like fences passing on both sides of them.

And by doing that, they could trick subjects

into thinking that their effort

was either allowing them to move forward, right?

Because these rungs on the fence were moving past,

or that their effort was futile,

that they were no longer moving forward

because they would make the rungs move slowly,

even though the subjects were making a lot of effort

to move forward, okay?

So this is analogous or similar to being on a treadmill,

and you’re trying to walk on this treadmill,

and you just can’t move the conveyor, right?

Or you’re in virtual reality,

and you’re putting a ton of effort,

but it seems like you’re moving excruciatingly slow.

I had this experience recently in real life.

I was doing a swim in the Pacific.

I was trying to go south,

and I was swimming, and I was caught in a current,

not the kind that pulls you out to ocean,

and I kept looking to my left,

and I saw this hotel on the shoreline,

and then I was swimming and swimming

and swimming and swimming,

and 20 minutes later, I looked to my left,

and the hotel is still exactly where it was before,

which meant that I wasn’t moving.

It felt futile.

Eventually, either the current changed or something changed,

and I eventually swam past the hotel,

got back on the beach, and eventually drove home.

That’s essentially what they did in this experiment,

but what they found was these neurons

that release epinephrine,

there’s another cell type called glia,

which actually means glue in Latin,

that is paying attention

to how much epinephrine is being released,

and at some point, the system reaches a threshold.

It reaches this threshold,

and it shuts off the release of more epinephrine.

It’s like, I quit, that’s it, no more effort signal.

If they could extend the time

before those glia said, ah, enough,

if they could release more adrenaline into the system,

then subjects would keep going.

So our desire to continue, or put differently,

our willingness to continue and our desire to quit

is mediated by events between our two ears.

Now, that doesn’t mean that the body’s not involved,

but it means that neurons are critically important.

So we have two categories of neurons that are important,

the ones in our head that tell us,

get up and go out and take that run,

and the ones that allow us,

encourage us to continue that run,

and we have neurons that shut things off,

that say no more.

And we, of course, have the neurons

that connect to our muscles and control our muscles.

But the reason we quit is rarely because our body quits,

our mind quits.

Now, I would never want to encourage people

to drive themselves to the point of injury.

That’s not going to be good for anybody,

but it is good to know that it’s neural.

Our ability to persist is neural.

So when people say, is it,

I hear that, you know, sports or effort or fighting,

or it’s 90% mental, 10% physical,

you know, that whole discussion about how much is mental,

how much is physical is absolutely silly.

It just proves that there’s no knowledge

of the underlying biology behind that statement.

It’s neither mental nor physical.

Everything is physical.

Everything is neurons.

Your thinking is the responsibility

of chemicals and electrical signals in your head.

So it’s not 90% mental, 10% physical.

It’s not 50-50.

It’s not 70-30.

It’s 100% nervous system.

It’s neurons, okay?

So when people say mental or physical,

understand it’s 100% neural.

And I’d love for the, how much of it is mental

and how much is physical to just disappear.

That argument means nothing and it’s not actionable.

Now, what do nerves need in order to continue to fire?

What do you need in order to get neurons to say,

I will persist?

Well, they need glucose.

Unless you’re a keto and ketogenic adapted,

you need carbohydrate is glucose.

That’s what neurons run on.

And you need electrolytes.

Neurons have what’s called a sodium potassium pump,

blah, blah, blah.

They generate electricity.

We could go into all this.

I will probably do an entire lecture

about the action potential,

but basically in order to get nerve cells to fire,

to contract muscle, to say, I’m going to continue,

you need sufficient sodium salt

because the action potential,

the actual firing of neurons is driven

by sodium entering the cell, rushing into the cell.

And then there’s a removal of potassium.

And then there’s a kind of resetting of those levels

by something called the sodium potassium pump

and the sodium potassium pump

and sodium and action potentials.

Even if you don’t know anything about that is ATP dependent.

It requires energy.

So you need energy in order to get neurons to fire.

And it is pH dependent.

It depends on the conditions

or the environment within the brain

being of a certain pH or acidity.

pH is about how acid or how basic the environment is.

And we will talk a little bit about pH

in simple terms that you can understand.

So nerves need salt.

They need potassium.

And it turns out they need magnesium

and you need glucose and carbohydrates

in order to power those neurons

unless you are running on ketones.

And to run on ketones,

you have to make sure that you’re fully keto adapted.

I will talk about adding in ketones

on top of carbohydrate at the end of the episode.

Okay, so that’s how nerves work.

You need carbohydrate,

you need sodium, potassium, and magnesium

in order to drive the brain.

Muscle, muscle is going to engage

and generate energy first

by using this phosphocreatine system.

High bouts of effort, really intense effort,

short-lived seconds to minutes,

but probably more like seconds

is going to be this phosphocreatine,

literally a fuel source in the muscle

that you’re going to burn

just like you would logs on a fire.

And glycogen, which is stored carbohydrate in the muscle,

that also can be burned

just like logs on a fire to generate energy.

So let me make this crystal clear.

If you move your wrist towards your shoulder

and contract your bicep really hard,

muscle fibers are burning up their own carbohydrate.

They’re converting that into ATP

in order to generate that energy, okay?

And pH is important and temperature is important.

In the episode on supercharge, your physical performance,

I talked all about how by using cooling

specifically of the palms or the bottoms of the feet

or the cheeks of the face using particular methods,

you can adjust the temperature of the body and of muscle

in a way that allows you to do more work,

to do more reps, to run further,

to keep going and to persist.

And that’s because if temperature is too low or too high,

then ATP is not going to be available

because of this whole thing

called the pyruvate kinase pathway

and the temperature dependence of pyruvate kinase.

Check out that episode

if you want to learn more about that,

but temperature is important and pH is also important.

So we’ve got nerve, muscle,

and then there’s stuff in our blood

that’s available as an energy source.

And in blood, we’ve got glucose,

so literally blood sugar that’s floating around.

So let’s say you have fasted for three days,

your blood glucose is going to be very low,

so that’s not going to be a great fuel source,

but you will start to liberate fats

from your adipose tissue, from your fat.

Fatty acids will start to mobilize into the bloodstream

and you can burn those for energy.

And oxygen in your blood,

when you inhale, you’re bringing oxygen into your blood.

So these are all fuel sources in your neurons,

in your muscle, in your blood,

in your various tissues that are providing the opportunity

to give effort, to induce effort,

whether or not it’s a run or a swim or writing or talking.

Now, there are some other factors that are important

and those are the heart, which is going to move blood.

So the more that the heart can move blood and oxygen,

well, the more fuel that’s going to be available

for you to engage in muscular effort and thinking effort.

So your heart is vitally important

to your muscle’s ability to work

and your brain’s ability to work.

And as I’ve mentioned, oxygen a few times,

it should be obvious then that the lungs are very important.

You need to bring oxygen in

and distribute it to all these tissues

because oxygen is critical

for the conversion of carbohydrates

and the conversion of fats.

And we could get into the discussion

about whether or not oxygen is important

for ketogenic metabolism, but you need oxygen there.

You need to breathe and you need to breathe properly.

So I just covered what would normally be

about four lectures of energy consumption

and energy utilization.

I didn’t go into much detail at all,

but what I want you to imagine

is that you’ve got these different cell types.

You’ve got neurons, you’ve got muscle.

They need to collaborate in order to generate effort

or to make the decision to do something or to think hard

or to run hard or to run far.

And then you’ve got fuel sources,

both in the neurons, in the muscle, in your blood.

And then the heart and lungs

are going to help distribute the oxygen and those fuels.

And of course you have that little energy pack

that we call the liver that will allow you

to pull out a little more carbohydrate

if you need it for work.

Okay, so that’s as much as I want to cover

about energy consumption because that’s a lot.

But what it tells you is that when you eat

and you use food as a fuel source,

that food can be broken down

and you can immediately burn the glucose

that’s in your bloodstream,

or you can rely on some of the stored fuel in your liver,

or you can rely on stored fuel in the muscle,

so-called glycogen.

And there are a lot of different ways

that we can generate ATP.

So when we ask the question,

what’s limiting for performance?

What is going to allow us to endure,

to engage in effort and endure long bouts of effort,

or even moderately long bouts of effort?

We need to ask which of those things,

nerve, muscle, blood, heart, and lungs is limiting.

Or put differently,

we ask what should we be doing with our neurons?

What should we be doing with our muscles?

What should we be doing with our blood?

What should we be doing with our heart?

And what should we be doing with our lungs

that’s going to allow us to build endurance

for mental and physical work

and to be able to go longer, further with more intensity?

That’s the real question.

How can we do more work?

And the way we do that is with energy.

And the way to get energy to it is by those five things.

And so now we’re going to talk about

how you can actually build different types of endurance

and what that does at the level of your blood,

your heart, your muscles, and your neurons.

So we’re going to skip back and forth

between protocols, tools, and the underlying science.

So rather than heavy stack the science at the front end

and then just give you all the tools at the end,

we’re going to talk about the protocols,

the four kinds of endurance and how to achieve them.

And we are going to talk about the underlying science

as we move through that.

If you would like a lot of detailed science,

I encourage you to check out a review

that we’ve linked in the show notes.

And the review is called

Adaptations to Endurance and Strength Training.

This is a review article with many excellent citations.

It’s from Cold Spring Harbor Perspectives in Medicine.

The Cold Spring Harbor Press

is an excellent scientific press.

It’s been the last 21 years,

doing summers at Cold Spring Harbor, teaching neuroscience.

But Cold Spring Harbor is involved

in all sorts of themes and topics

related to neuroscience and medicine.

This review by Hughes Eliphason,

Eliphason, that’s the name, Eliphason and Barr, B-A-A-R,

Adaptations to Endurance and Strength Training,

is rich with citations.

It can be downloaded as a complete PDF.

There’s no paywall and we will link to it.

And it gets really deep into all the signaling cascades,

the genetic changes within muscle

with high intensity interval training,

short-term super high intensity training, weight training.

So if you’re a real nerd for this stuff

and you want to get right down into how PGC-1-alpha,

P53 and PH20 change the adaptation features

of muscle and gene regulation,

that is definitely the review for you.

If you’re like most people

and you’re not really interested in that level of detail,

no reason to pick up the review

unless you just want to check out

some of the figures and pictures.

But I do want to offer that as a resource.

It’s been, in addition to discussions with Dr. Andy Galpin,

it’s been a primary resource

for the content of this episode.

So let’s talk about the four kinds of endurance

and how to achieve those.

I do believe that everybody should have

some sort of endurance practice,

regular endurance practice.

It’s clear that it’s vital for the functioning of the body

and the mind, and there are clear longevity benefits.

There are a lot of reasons why that’s true,

but the main one is that

if we have good energy utilization in our musculature

and in our blood, in our vascular system,

and in our oxygenating system, our lungs,

the so-called cardiovascular system,

respiratory system, and musculature,

the body and brain function much better.

There are so many papers now, so much data to support that.

So I do believe everyone should either try

to maintain the muscle that they have,

provided they’ve already gone through puberty

and development, and they should be engaged

in regular endurance exercise.

Now, for many people, they think endurance exercise,

that means what, an hour-long run,

or I got to get on the Stairmaster,

or I have to treadmill for hours on end each week.

It turns out that’s not the case.

There are four kinds of endurance,

and you can train specifically for any one of those,

and you can vary your training.

So let’s talk about those four kinds of endurance,

because they’re very interesting,

and they each have very different protocols

that you use in order to build and maximize them,

and now you’ll understand what fuel sources they use

in order to build that thing we call endurance.

So first of all, we have muscular endurance.

Muscular endurance is the ability for our muscles

to perform work over time,

and our failure to continue to be able to perform that work

is going to be due to muscular fatigue,

not to cardiovascular fatigue.

So not because we’re breathing too hard,

or we can’t get enough blood to the muscles,

or because we quit mentally,

but because the muscles themselves give out, okay?

One good example of this would be

if you had to pick up a stone in the yard,

and that stone is not extremely heavy for you,

and you needed to do that anywhere from 50 to 100 times,

and you were picking it up and putting it down,

and picking it up and putting it down,

and picking up and putting it down,

at some point, your muscles will fatigue,

they will fail to endure.

Muscular endurance is incredibly useful

for a variety of physical pursuits,

and we will talk about the mental pursuits

that it supports as well.

In terms of physical pursuits,

the ability for a given muscle to perform repeated work

is going to improve your golf swing,

it’s going to improve your tennis swing,

it’s going to improve your posture, your ability to dance,

your ability to repeatedly engage in an activity

that requires effort in a way that’s very different

from the kind of endurance that you will build

simply by increasing your cardiovascular fitness,

your ability to generate kind of easy repetition.

So let’s talk about muscular endurance and what it is.

Muscular endurance is going to be something

that you can perform for anywhere from 12 to 25,

or even up to 100 repetitions,

and that’s actually how, if you like,

you would train muscular endurance,

and I will give the specific protocol in a few moments.

So a good example is pushups, right?

If you were to get on the floor and start doing pushups,

even if you’re somebody who has to do knees down pushups,

and you’re doing your pushups,

eventually you won’t be able to do any more pushups,

and that’s not going to be

because you couldn’t get enough oxygen into your system

or your heart wasn’t pumping enough blood,

it’s going to be because the muscles fail, that’s why.

So if you want to be able to do more pushups

or even more pull-ups,

muscular endurance is really what it’s about.

It’s actually no coincidence

that a lot of military bootcamp style training

is not done with weights,

it’s done with things like pushups, pull-ups,

sit-ups, and running,

because what they’re really building is muscular endurance,

the ability to perform work repeatedly over time

for a given set of muscles and neurons.

So what’s a good protocol to build muscular endurance?

Let’s just give that to you now

and explain some of the underlying science as it follows.

So a really good muscular endurance training protocol,

according to the scientific literature,

would be three to five sets

of anywhere from 12 to 100 repetitions.

That’s a huge range.

Now, 12 to 25 repetitions

is going to be more reasonable for most people.

And the rest periods are going to be

anywhere from 30 to 180 seconds of rest.

So anywhere from half a minute to three minutes of rest.

So this might be five sets of pushups,

done getting your maximum pushups,

so for some people that might be zero

and you have to do it knees down.

For some people it might be 10 pushups,

for some people it might be 25,

but you could go all the way up to 100,

rest anywhere from 30 to 180 seconds,

and then do your next set for a total of three to five sets.

So it doesn’t actually sound like a ton of work.

The other thing you could do is something like a plank.

A plank position is actually a way

to build muscular endurance, not strength, okay?

I’m sure it could be used to develop strength,

but it’s really about muscular endurance.

So you would do three to five sets of planks.

Those planks would probably,

even because you’re not doing repetitions,

it’s an isometric hold, as we say,

it’s kind of static hold,

or a wall sit would be another example.

And you would do that probably for a minute or two minutes,

take some rest of anywhere from 30 to 60 or 180 seconds,

and then repeat.

So things like pushing a sled, pushups, isometric planks,

even pull-ups, those will all work.

And as with other forms of training,

you would want to do this until you approach failure

or actually fail,

and where you’re unable to perform another repetition,

that would mark the end of a set.

The one critical feature of building muscular endurance

is that it has no major eccentric loading component.

Now, I haven’t talked much about eccentric

and concentric loading,

but concentric loading

is when you are shortening the muscle, typically,

or lifting a weight,

and eccentric movements

are when you are lengthening a muscle, typically,

or lowering a weight.

So if you do a pull-up

and you get your chin over the bar or a chin-up,

that’s the concentric portion of the effort.

And then as you lower yourself,

that’s the eccentric portion.

Eccentric portion of resistance training of any kind,

whether or not it’s for endurance or for strength,

is one of the major causes of soreness.

Some people will be more susceptible to this, excuse me,

than others,

but it does create more damage in muscle fibers.

Muscular endurance and building muscular endurance

should not include any movements

that include major eccentric loads.

So if you’re going to do push-ups,

it doesn’t mean that you want to drop,

you know, smash your chest into the floor.

And by the way,

your chest should touch the ground on every push-up.

That’s a real push-up, okay?

It’s not about breaking 90 with the elbows.

It’s about pushing down till your chest touch the floor

and straightening out.

That’s a proper push-up.

And a pull-up is where you pull your chin above the bar.

Neither of those should include a slow eccentric

or lowering component.

If you are using those to train muscular endurance,

the three to five sets of 12 to 25,

and maybe even up to a hundred repetitions

with 30 to 180 seconds of rest in between.

That means that jumping also is going to be a very poor tool

for building muscular endurance

because jumping has a slowing down component as you land.

So things like plyometrics or agility work

where you’re moving from side to side

and you’re decelerating,

you’re slowing yourself down a lot,

not going to be good for muscular endurance.

Terrific for cardiovascular training

and conditioning of other kinds

and skill training and agility and all that.

But if you want to build muscular endurance,

you want to make your muscles able

to do more work for longer,

it’s going to be this three to five sets

of 12 to a hundred reps,

30 to 180 seconds of mainly concentric movement, okay?

Not a slow lowering phase or a heavy lowering phase.

So that might be kettlebell swings

and things of that sort.

Isometrics, as I mentioned,

things like plank and wall sits will work.

Now, what’s interesting about this

is that it doesn’t seem at all

like what people normally think of as endurance.

And yet it’s been shown

in nice quality peer reviewed studies,

several of which are cited in the review

I mentioned earlier,

that muscular endurance can improve our ability

to engage in long bouts of what we call long duration,

low intensity endurance work.

So this can support long runs,

it can support long swims,

and it can build also,

it can build postural strength

and endurance simultaneously.

And that’s mainly accomplished through isometric hold.

So things like planks are actually quite good

for building endurance of the spinal erector muscles

that provide posture of the abdominal muscles

that are helpful for posture,

for being upright,

for the upper neck muscles and things of that sort.

These days, everyone seems to have text neck.

Everyone’s basically staring at their toes all the time.

It has a default towards their toes.

So isometric holds can be very good

for building muscular endurance.

You can spot people, including yourself,

perhaps with poor muscular endurance

in the postural muscles,

because anytime they stop moving,

they have to lean against a wall

or their hip will move to one side

or they’re always lean to one side.

I am guilty of this too.

Some of you have actually pointed out,

I like to think out of concern

that I often am rubbing my lower back.

And indeed I have some asymmetries in my postural muscles,

some of which are probably genetic

and some of which are probably just from excessive work

or something of that sort

that have my right shoulder sit lower than my left

and things of that sort.

If I wanted to improve those,

I could improve those by really focusing on symmetry

and isometric symmetry,

meaning holding my hands at equivalent positions in planks

and doing isometric holds

for building muscular endurance of the postural muscles.

But this can also be done with, as I mentioned,

kettlebell swings for the lower back and legs

and posterior chain.

So there are a number of different exercise

you could do this with,

but it should be compound exercises mainly.

It’s rare for people to do

this kind of muscular endurance work

specifically for things like bicep curls or triceps.

And there aren’t many activities

that really rely on isolation of those muscles repeatedly.

I’m sure there are some out there,

but it’s kind of hard to imagine.

So you can do this with isometrics,

you can do this with more standard

non-isometric type movements,

but make sure there isn’t a strong eccentric load.

So now let’s talk about the science briefly

of why this works.

Well, that takes us back to this issue of fuel utilization

and what fails.

So if we were to say, okay, let’s say you do a plank

and you’re planking for, you know,

maybe you’re able to plank for a minute or two minutes

or three minutes, at some point you will fail.

You’re not going to fail because the heart gives out.

You’re not going to fail

because you can’t get enough oxygen

because you can breathe while you’re doing that.

You’re going to fail because of local muscular failure,

which means that as you do,

if you choose to do this protocol of three to five sets,

et cetera, et cetera, to build muscular endurance,

mainly what you are going to be building

is you’re going to be building the ability

of your mitochondria to use oxygen

to generate energy locally.

And that it’s something called mitochondrial respiration,

because of the involvement of oxygen.

And it’s also going to be increasing the extent

to which the neurons control the muscles

and provide a stimulus for the muscles to contract.

But this is independent of power and strength, okay?

So even though the low sets, like three to five sets,

and the fact that you’re doing repetitions

and you’re going to failure,

even though it seems to resemble power and strength

and hypertrophy type training,

it is distinctly different.

It’s not going to generate strength, hypertrophy, and power.

It’s going to mainly create this ability to endure,

to continually contract muscles

or repeatedly contract muscles, okay?

Continually, if you’re using isometric holds,

repeatedly, excuse me,

if you’re using repetition type exercise,

where there’s a contraction and an extension of the muscle,

essentially concentric and an eccentric portion.

But remember that you want the eccentric portion

to be light and relatively fast,

not so fast that you injure yourself,

but certainly not deliberately slowed down.

It was recommended, I should say, by Andy Galpin

that you not use Olympic lifts for this,

because once you get past eight or 12 or 25 repetitions,

especially form on those Olympic lifts

is key for not getting injured.

And while some people can perform those sorts of lifts,

like snatches and deadlifts and cleans and jerks

and overhead presses, probably not a great idea

if the goal is to push the body to points of fatigue,

because you do open yourself up to injury,

unless you’re very skilled at doing that,

or you have a really good coach

who can help you guide through those lifts.

So that’s one form of endurance,

which is muscular endurance,

and it’s mainly going to rely on neural energy,

so nerves and muscle.

And it’s not going to rely quite so much

on what’s available in your blood,

your heart, or your lungs.

So now let’s talk about the other extreme of endurance,

which is long duration endurance.

This is the type that people typically think about

when they think about endurance.

You’re talking about a long run, a long swim,

a long bike ride.

Well, how long?

Well, anywhere from 12 minutes to several hours,

or maybe even an entire day,

maybe eight or nine hours of hiking or running or biking.

Some people are actually doing

those kinds of really long events,

marathons, for instance.

So anything longer than 12 minutes.

And this type of work builds on fuel utilization

in the muscles.

It builds on the activity of neurons in the brain

that are involved in what we call

central pattern generators.

We talked about this in a previous episode,

or several previous episodes.

These are groups of neurons that allow our body

to engage in regular rhythmic effort

without having to think about the movement too much.

So running and stepping,

or swimming if you already know how to swim,

or pedaling on a bike,

or walking upstairs and hiking.

You’re not thinking about right, left, right, left.

It’s all carried out by central pattern generators.

This is going to be at less than 100%

of your maximum oxygen uptake, your VO2 max.

I’ll talk about what VO2 max is,

but I just want to give a sense of what the protocol is

and the underlying science.

How many sets?


Long duration effort is one set of 12 minutes or longer.

So you’re not counting repetitions.

I sure hope that if you’re going out on a 30 minute run,

or even a 15 minute run, that you’re not counting steps,

that you’re not counting pedal strokes,

that you’re not on the rower counting pulls on the rower.

I suppose you could,

but I think that would be pretty dreadful.

Seems like a poor utilization of cognitive brain space.

You’re getting into regular repeated effort,

and your ability to continue that effort

is going to be dependent mainly

on the efficiency of the movement,

on your ability to strike a balance

between the movement itself,

the generation of the muscular movements that are required,

and fuel utilization across the different sources

of nerve, muscle, blood, heart, and lungs.

So let’s ask the question,

why would you fail on a long run?

Why would you quit?

Well, as you set out on that long run,

assuming you have some glycogen in your liver

and in your muscles,

you’re going to use that energy first,

even if it’s very low intensity.

Okay, so we’re not talking about sprinting.

We’re talking about heading out the door

or starting off on a marathon.

You’re starting to,

assuming you have some conditioning,

or even if you don’t, you’re going to burn carbohydrate.

You’re going to burn glucose in the bloodstream.

You’re going to burn carbohydrate

as those muscles contract,

those what we call slow twitch muscles.

They’re contracting.

You start burning up fuel to make ATP

to continue to contract.

Your mind is going to use more or less energy

depending on how much willpower,

how much of a fight you have to get into with yourself

in order to generate the effort.

I really want to underscore this.

If you’re somebody that’s thinking,

maybe I go for the run,

maybe I don’t go for the run.

I’ll do it at two o’clock.

Okay, 205.

No, I only want to go on the half hour

or maybe on the main hour.

And you’re going through all that.

Guess what?

You’re burning up useful energy

that you could use either for the run,

for example, or for something else.

When we think about something hard,

when we ruminate,

when we perseverate on an idea or on a decision,

we are burning neural energy

and neural energy is glucose and epinephrine

and all the things we talked about before.

So willpower in part is the ability to devote resources

to things and part of that is making decisions

to just either do it or not do it.

I’m not of the just do it mindset.

I think there’s a right time and a place to train,

but I also think that it is not good.

In other words, it utilizes excessive resources

to churn over decisions excessively.

And you probably burn as much cognitive energy

deciding about whether or not to do a given training

or not as you do in the actual training.

So we’ll talk more about how this long duration effort

can relate to mental performance,

but the long duration effort should be one set,

12 minutes or longer.

It could go for 30 minutes or 60 minutes or an hour.

We’ll talk about programming later in the episode.

This is going to be less than 100%

of your maximum oxygen uptake.

Your heart rate is not going to be through the ceiling

or maxed out,

but it’s all about efficiency of movement.

That’s what you’re building.

When you go out for a run that’s 30 minutes,

you are building the capacity to repeat that performance

the next time while being more efficient,

actually burning less fuel.

And that might seem a little bit counterintuitive,

but every time you do that run,

what you’re doing is you’re building up

mitochondrial density.

It’s not so much about mitochondrial oxidation

and respiration.

You’re building up mitochondrial density.

You’re actually increasing the amount of ATP

that you can create for a given bout of effort.

You’re becoming more efficient, okay?

You’re burning less fuel overall, doing the same thing.

That’s really what these long, slow distance

or long bouts of effort are really all about.

Now, why do this long duration effort?

Why would you want to do it?

Why is it good for you?

Well, it does something very important,

which is that it builds the capillary beds within muscles.

So let’s talk a little bit about vasculature.

We haven’t done this too much yet,

but if you have seen the episode

on supercharging performance, we talked about AVAs,

these arteriovenous asthmosis,

where blood moves from arteries directly into veins,

but that’s unusual.

That only takes place in the so-called glabrous skin

of the palms, the face, and the bottoms of the feet.

Typically, for most all other areas of the body,

what happens is arteries bring blood

to a given tissue, like a muscle,

and veins return that blood back to the heart.

There are exceptions, but in general.

And in between arteries and veins are these little tiny,

what are called capillary beds or microcapillaries.

So these are tiny little avenues,

like little tiny streams and estuaries

between the bigger arteries and veins.

Now, those are actually contained within muscle.

And what’s amazing is that you can increase

the number of them.

You can literally build new capillaries.

You can create new little streams within your muscles.

And the type of long duration effort

that I was talking about before,

12 minutes or more of steady effort,

is very useful for doing that,

and is very useful for increasing the mitochondria,

the energy producing elements of the cells,

the actual muscle cells.

And the reason is when blood arrives to muscles,

it has oxygen.

The muscles are going to use some of that oxygen,

and then some of the deoxygenated blood

is going to be sent back to the heart and to the lungs.

Now, the more capillaries that you build into those muscles,

the more oxygen available to those muscles.

I don’t want to get too much into the physics

of fluid flow, but basically it’s the difference

between taking a hose and sticking it into some dirt

just directly, and turning on the faucet at a given rate,

the spigot rather, or having a bunch of little hoses,

like a sprinkler system that go out

and irrigate the whole yard.

The irrigation is equivalent to this capillary bed system.

And it’s very good at using energy sources within blood.

So the simple way to think about this

is when you go out for a run,

let’s say it’s the first run you’ve done for a while,

and you go out for 12 or 15 minutes,

and somewhere right around 20 minutes,

you’re like, that’s it, I just can’t continue.

Well, when you come back the next time to do that run,

you’ve built endurance,

largely because you’ve built these capillary beds.

You’ve expanded these little streams

in which blood can deliver oxygen to the muscles.

And so it’s going to feel relatively straightforward

to either go a little bit quicker for the same duration,

the same distance,

or to extend that run for another five to 10 minutes.

So this long duration work,

unlike muscular endurance like planks

and everything that we were talking about before,

is really about building the capillary systems

and the mitochondria,

the energy utilization systems

within the muscles themselves.

And that’s very important to understand.

It’s distinctly different than say,

building the neurons that fire the muscles.

The neurons are already there.

They’re going to fire those muscles just fine.

In fact, if your life depended on it today,

you could probably run a marathon.

You’d probably get injured.

It would be very psychologically and physically painful.

I don’t recommend you do that unless you’re trained for it.

But if you were to train properly for it,

if you were to do long duration bouts of effort

once or twice a week, or three times a week,

pretty soon it would become easy

because you’re building these vascular microbeds

or microvascular beds as they’re called.

Okay, so you’re able to bring more energy to the muscles

and they’re able to utilize more energy.

So that’s long duration.

So we’ve got muscular endurance

and we’ve got long duration endurance.

And then there are two kinds in between

that in recent years have gotten a lot of attention

and excitement, but most people are not distinguishing

between these two kinds of endurance.

And that’s a shame because in failing to distinguish

between the two kinds of what we call

high intensity training,

sometimes called high intensity interval training,

most people, perhaps you,

are not getting nearly as much physical

and mental benefit out of high intensity training

as you could.

So I want to talk about the two kinds

of high intensity interval training

and what each of them does for your brain and body

and what sorts of adaptations they cause.

Because in doing that, you can really start

to build up specific energy systems in your brain and body

in ways that are best serve you for your cognitive work

and for other sorts of things

like strength and speed or hypertrophy

or for running marathons for that matter.

So there are two kinds of high intensity training

for endurance, sometimes called

high intensity interval training.

One is anaerobic, so-called anaerobic endurance,

so no oxygen, and the other is aerobic endurance,

both of which qualify as HIIT,

high intensity interval training.

So let’s talk about anaerobic endurance first.

Anaerobic endurance from a protocol perspective

is going to be three to 12 sets, okay?

And these repetitions,

and I’ll talk about what the repetitions are,

are going to be performed at whatever speed allows you

to complete the work in good, safe form, okay?

So it could be fast, it could be slow.

As the work continues, your repetitions may slow down

or it may speed up, chances are it’s going to slow down.

So what does this work, what do these sets look like?

Remember, long, slow distance is one set.

Muscular endurance is three to five sets.

High intensity anaerobic endurance

is going to be somewhere between three and 12 sets.

And it’s going to have a ratio of work to rest

of anywhere from three to one to one to five, okay?

So what would a three to one ratio set look like?

Well, it’s going to be 30 seconds

of hard pedaling on the bike, for instance,

or running, or on the rower.

These are just examples.

It could be in the pool swimming,

it could be any number of things,

or air squats, or weighted squats, if you will,

provided you can manage that.

30 seconds on, 10 seconds off.

That’s a very brief rest.

So three to one is just a good example,

would be 30 seconds on, 10 seconds off.

The opposite extreme on that ratio would be one to five,

so 20 seconds on, 100 seconds off.

So you do the work for 20 seconds,

then you rest 100 seconds.

Now, what’s the difference?

Should you do three to one ratio,

so 30 seconds on, 10 seconds off,

or should you do one to five,

20 seconds on to 100 seconds off?

Well, that will depend on whether or not

the quality of the movement is important to you.

So let’s just take a look at the three to one ratio.

So in the three to one ratio,

if you’re going to do 30 seconds

of hard pedaling on a bike, followed by 10 seconds,

so maybe one of these, what they call assault bikes,

and then you stop for 10 seconds and then repeat,

chances are you will be able to do one, two, three, four,

maybe even as many as 12 sets

if you’re really in good condition,

that you’ll be able to do all those

because pedaling on the bike doesn’t require a ton of skill.

And if you do it incorrectly,

if your elbow flares out a little bit or something,

it’s very unlikely that you’ll get injured

unless it’s really extreme, okay?

But the same movement done, for instance, with kettlebells,

so 30 seconds on, 10 seconds off,

the first set will probably be in good form.

The second one will be in pretty good form,

but let’s say you’re getting to the fifth and sixth set

and you’re going 30 seconds on, 10 seconds off,

chances are the quality of your repetitions

will degrade significantly

and you increase the probability

that you’re going to get injured

or that you’re going to damage yourself in some way

or that you can’t complete the movement

or that some smaller muscles,

like your grip muscles might give out, okay?

So the quality of repetitions is going to drop considerably

with the three-to-one approach.

If you’re just doing it for effort,

and we’ll talk about what this builds in your system

in a moment, that’s fine.

But for most people, if quality of form is important,

so maybe this is using weights, maybe you’re doing squats,

so you’re going to do 20 seconds on

and 100 seconds of rest.

Maybe it’s even a barbell loaded squat,

maybe you’re doing kettlebells,

maybe you’ve got some other resistance there

that’s allowing you to do this.

What you’ll find is that the longer rest,

even though it’s 20 seconds of intense effort

followed by a longer rest of about 100 seconds

will allow you to perform more quality repetitions

safely over time.

So what does building anaerobic endurance look like?

And then I’ll tell you what it’s actually good for

in the true practical sense.

What anaerobic endurance exercise generally looks like

is that if you decide to do this for the first week,

you might do this two or three times a week,

maybe even just once a week,

depending on the other things you’re doing.

We’ll talk about programming at the end.

And you would generate just three sets.

So it might be three sets of 20 seconds of hard effort

followed by 100 seconds rest.

Then you repeat 20 seconds of hard effort,

100 seconds rest, 20 seconds of hard, 100 seconds rest.

And you might do that twice a week.

And then each week you’re adding one or two sets.

Okay, in doing that,

you will build up what we call anaerobic endurance.

What is anaerobic endurance?

Well, let’s ask why we fail.

Anaerobic endurance is going to be taking your system

into greater than 100% of your VO2 max.

It’s going to be taking your heart rate up very high,

and it’s going to maximize your oxygen utilization systems.

That is going to have effects

that are going to lead to fatigue

at some point in the workout.

And that fatigue will trigger an adaptation.

So let’s ask what adaptation it’s triggering.

Well, it’s triggering both mitochondrial respiration,

the ability of your mitochondria to generate more energy

by using more oxygen because you’re bringing so,

you’re maxing out,

literally you’re getting above your VO2 max.

You’re hitting that threshold

of how much oxygen you can use in your system.

One of the adaptations will be that your mitochondria

will shift such that they can use more oxygen.

And you’re going to also increase the capillary beds,

but not as much as you’re going to be able

to increase the amount of neuron engagement of muscle.

So normally when we start to hit fatigue,

when we’re exhausted, when we’re breathing really hard,

because the systems of the body are linked

and there’s a mental component to this as well,

a kind of motivational component.

After that third or fourth or sixth set of 20 seconds on,

100 seconds off,

or if you’re at the other extreme,

30 seconds on and 10 seconds off,

there’s going to be a component of you want to stop

and by pushing through and repeating another set safely,

of course, what you’re doing is you’re training the neurons

to be able to access more energy,

literally convert that into ATP and for the muscles,

therefore to access more energy and ATP.

And the adaptation is in the mitochondria’s ability

to use oxygen.

And this has tremendous carryover effects

for other types of exercise.

So while I know and appreciate that people are using

high intensity interval training of this kind or similar

in order to just like burn fat,

do their workouts, quote unquote,

it’s very useful for building a capacity

to engage in short bouts of effort repeatedly,

to really lock in.

I don’t want to use the word focus

because it’s not strictly mental focus,

but to be able to generate short bouts of very intense work.

This can be beneficial in competitive sports or team sports

where there’s a sprinting component,

where the field opens up and you need to dribble the ball

down the field, for instance, and shoot on goal,

or where you’re playing tennis and it’s a long rally

and then all of a sudden somebody really starts

putting you back on your heels

and you have to really make the maximum amount of effort

to run to the net and to get the ball across that,

things of that sort, okay?

There are a variety of places where there’s carryover

from this type of training, but it does support endurance.

It’s about muscle endurance.

It’s about these muscles’ ability to generate

a lot of force in the short term, but repeatedly, okay?

So that’s the way to conceptualize this.

And it is different than maximum power.

Even though it feels like maximum effort,

it is not the same as building power

and speed into muscles.

Those are distinctly different protocols.

So the key elements again are that you’re bringing

your breathing and your oxygen utilization

way up above your max.

It’s not quite hitting failure,

but you’re really pushing the system to the point

where you are not ready to do another set

and yet you begin another set.

You’re not necessarily psychologically ready.

I’ll talk more about some of the adaptations

that this causes in terms of stroke volume in a few minutes

when we talk about how it is that work of this sort

can increase our heart’s ability to deliver blood

and oxygen to our lungs and other tissues.

I’m going to get very specific about how to breathe

during these different types of protocols

and what’s happening at the level of the heart,

but I want to make sure I touch on the fourth protocol,

which is high-intensity aerobic conditioning.

So HIT has these two forms, anaerobic and aerobic,

and you just heard about anaerobic.

High-intensity aerobic conditioning

also involves about three to 12 sets,

starting off of course with fewer sets

as you’re getting into this training

and then extending into more sets

as one parameter you could expand.

Has again, the same ratio of three to one,

so 30 seconds on, 10 seconds off, or one to five,

20 seconds on, 100 seconds off,

or a very powerful tool for building up aerobic conditioning

is a one-to-one ratio.

A one-to-one ratio is powerful for building on average

most of the energy systems involving,

remember we had these nerve, muscle, blood, heart, and lungs,

a one-to-one ratio might be you run a mile

and however long that takes,

let’s say it takes you six minutes or seven minutes,

then you rest for an equivalent amount of time,

then you repeat and then you rest

for an equivalent amount of time.

So you might run first mile as let’s say seven minutes,

then you rest for seven minutes,

then you run a mile again and it might take eight minutes

and you rest for eight minutes.

And you continue that for a total of four miles of work,

for four miles of running work, I should say,

or seven miles of work.

You can build this up.

Many people find that using this type of training

allows them to do things like go run half marathons

and marathons, even though prior to the race date,

they’ve never actually run a half marathon or marathon.

Now that might seem incredible.

It’s like, how could it be that running a mile on

and then resting for an equivalent amount of time,

running a mile, resting for equivalent amount of time

for seven miles allows you to run continuously for 13 miles

or for 26 miles?

Well, I’m not discouraging people

from ever doing the long duration endurance.

I think that is very important,

but it’s because it builds up

so many of these energy utilization systems.

It really teaches you to engage, excuse me,

the nerve to muscle firing.

It improves ATP and mitochondrial function in muscle.

It allows the blood to deliver more oxygen to the muscle

and to your brain.

And I’ll explain how that is.

And it allows your heart to deliver more oxygen overall.

And it builds a tremendous lung capacity.

And we will talk about exactly how to breathe

and how to build lung capacity,

both for sake of warming up and for performance.

So what would this look like?

And when should you do this?

Well, it’s really a question for these workouts

of asking how much work can one do

in eight to 12 minutes, right?

And then rest and then repeat.

How much work can you do for eight to 12 minutes

then rest and then repeat?

And how many times should you do this?

Well, this is the sort of thing, it’s pretty intense.

And so you would probably only want to do this

two, maybe three times a week

if you’re not doing many other things.

I will talk about how this program can be moved in

with other forms of training,

but I’ll just give you a little hint now.

It’s very clear and it’s described

in the review article referred to,

and we will link another article as well,

that concurrent training, doing strength training

and the endurance training of any of the four kinds

that I’m describing today can be done.

You can program those in the same week,

but you want to get four and ideally six

or even better 24 hours between these workouts

because it is very hard for instance,

to do a one-to-one mile repeats,

like run a mile, rest for equivalent time,

run a mile, rest for equivalent time,

to do that two or three times a week

and also do weight training before

or do a long run afterwards.

That would quickly lead to breakdown for most people

unless you have very, very good energy utilization systems,

you’re a really kind of advanced or elite athlete

and or dare I say, you’re using tools

to enhance your performance at the level of blood

or hormones and I’m actually going to talk about those

at the end and why they work.

So we have four kinds of endurance, muscular endurance,

we have long duration endurance,

we have high intensity interval training of two kinds,

anaerobic and aerobic, and this last type,

the aerobic one works best it seems

if you kind of do this one-to-one ratio.

So how would you use these and what are they actually doing?

Let’s talk about the heart and the lungs and oxygen

because that’s something that we can all benefit

from understanding and it will become very clear

in that discussion why this type of training is very useful

even for non-athletes in order to improve oxygenation

and energy utilization of the brain and the heart.

The brain and the heart are probably

the two most important systems that you need

to take care of in your life.

Yes, your musculature needs to be maintained.

If you want to build it, that’s up to you

but you should try and maintain your musculature

but maintaining or enhancing a brain function

and cardiovascular function, it’s absolutely clear

our key for health and longevity in the short and long term

and the sorts of training I talked about today

has been shown again and again and again to be very useful

for enhancing the strength of the mind,

yes, I’ll talk about that,

as well as the health of the brain and the body.

So let’s talk about the sorts of adaptations

that are happening in your brain and body

that are so beneficial in these different forms of training.

If you are breathing hard and your heart is beating hard,

so this would be certainly in the high-intensity

anaerobic and aerobic conditioning

because you’re getting up near your VO2 max

in high-intensity aerobic conditioning

and you’re exceeding your VO2 max

in high-intensity anaerobic conditioning,

what’s going to happen is,

as of course your heart beats faster,

your blood is going to be circulating faster in principle,

oxygen utilization in muscles is going to go up

and over time, not long, very quickly,

what will happen when those capillary beds start to expand,

we talked about that,

but in addition, because of the amount of blood

that’s being returned to the heart

when you engage in these really intense

bouts of effort repeatedly,

the amount of blood being returned to the heart

actually causes an eccentric loading

of one of the muscular walls of the heart.

So your heart is muscle, it’s cardiac muscle.

We have skeletal muscle attached to our bones

and we have cardiac muscle, which is our heart.

When more blood is being returned to the heart

because of the additional work

that your muscles and nerves are doing,

it actually has the effect of creating an eccentric loading,

a kind of pushing of the wall, the left wall.

I realize I’m not using the strict anatomy here,

but I don’t want to get into all the features

of the structural features of the heart,

but the left ventricle essentially getting slammed back

and then having to push back

in a kind of eccentric loading of the cardiac muscle

and the muscle thickens,

but not because the heart thickens overall,

it’s actually a strengthening of the cardiac muscle

in a way that increases what we call stroke volume.

Meaning as more blood is returned to the heart,

there’s an adaptation where the heart muscle

actually gets stronger

and therefore can pump more blood per stroke, per beat.

And as it does that, it delivers,

because blood contains glucose and oxygen and other things,

it delivers more fuel to your muscles,

which allows you to do yet more work per unit time.

Okay, so when we hear that, oh, you know,

so-and-so has a, or maybe you have a nice low heart rate

that, you know, maybe you’re one of these

really extreme folks like 30 or 40 beats per minute,

although most people are sitting at 50, 60, 70, 80,

that’s your resting heart rate.

If you exercise regularly

and you do long duration aerobic work,

your heart rate will start to go down,

your resting heart rate.

It will increase the stroke volume of your heart.

If you do this high intensity type training

where your heart is beating very hard,

so maybe the one-to-one ratio mile run repeats

that I described a minute ago,

let’s say you do that twice a week for three or four,

and I said it could go all the way up to 12 sets,

which is a lot, I don’t recommend people start there.

Pretty soon, the stroke volume of your heart

will really increase, and as a consequence,

you can deliver more fuel to your muscles and to your brain

and you will notice that you can do more work,

meaning you can do the same work you were doing

a few days or weeks ago with relative ease,

your cognitive functioning will improve.

This has been shown again and again

because there’s an increase in vasculature,

literally capillary beds within the brain,

the hippocampus areas that support memory,

but also areas of the brain that support respiration,

that support focus, that support effort.

This isn’t often discussed,

but the ability to deliver more blood

and therefore more glucose,

remember neurons run on glucose,

and oxygen to the brain is a big feature

of why exercise of the kind I’m describing

helps with brain function.

Now, weight training does have some positive effects

on brain function also.

When I say weight training, I should be more specific,

I really am referring to strength and hypertrophy training.

Strength and hypertrophy training,

especially if it’s of the sort where you get into the burn,

as we talked about last episode,

and you start generating lactate as a hormonal signal

that can benefit your brain, et cetera,

it can have positive effects on the brain.

And frankly, there haven’t been as many studies

of resistance training,

strength and hypertrophy training on brain function,

mainly because most of those experiments

are done in mice or primates, non-human primates,

I should say,

and it’s hard to get mice to do resistance training.

It’s hard to get humans to do resistance training.

It’s definitely hard to get mice to do resistance training.

There are ways to do it,

but it’s hard to get them to do, say,

three sets of eight on the deadlift,

and then do some curls,

and then do some chin-ups, and this kind of thing.

It’s pretty easy to get a mouse to run on a treadmill,

and you can set the tension on that treadmill

to make it so that it’s easier or harder

for the mouse to turn that wheel.

So that’s one of the reasons.

However, it’s very clear,

and you should now understand intuitively

why the kind of standard strength

and hypertrophy type workouts

are not going to activate the blood oxygenation

and the stroke volume increases for the heart

that the sorts of training I’m talking about today will.

It just doesn’t have the same positive effects.

Now, that isn’t to say that if you just weight train

that you’ll be dumb

or that you’ll lose your memory over time.

You might, but it is to say that endurance work,

in particular, the high-intensity and long-duration work

that I’ve talked about today,

the two high-intensity protocols and the long-duration work

has been shown again and again and again

to have positive effects on brain function,

not through the addition of new neurons.

Sorry to break it to you,

but that’s not a major event

in the exercised or non-exercised human brain

for reasons we can talk about in a future episode,

but it still has many positive effects

through the delivery of things like IGF-1,

but also just through plain oxygenation of the brain

and the way it promotes the development

of microvasculature to deliver neurons more nutrients.

If neurons don’t get oxygen and glucose, they do die,

unless there’s another fuel source like ketones,

which can replace the glucose.

If you don’t give oxygen to neurons,

if you don’t deliver enough to them,

you get what’s called ischemia, you get little microstrokes.

So the type of exercise I’m talking about today

in generating intense heart rate increases,

provided that’s safe for you to do,

breathing hard, that’s going to deliver oxygen and blood,

increase stroke volume of the heart,

and is going to improve brain function.

This has been supported by many, many

quality peer-reviewed studies.

So that’s one form of positive adaptation.

I also talked about just sort of performance adaptations,

how doing high-intensity aerobic conditioning

of the mile repeats type training

can actually improve your ability

to do long bouts of intense work.

It also seems like it dovetails or is compatible

with resistance training that’s aimed

towards strength and hypertrophy.

Now, in full disclosure, the data seem to indicate

that if people just weight train or train for strength,

so three reps, rest five minutes,

three reps of heavy weights, et cetera,

yeah, you’ll get much stronger than you would

if you’re doing things like five repetitions up to 12

or 12 to 25 reps and you’re going out for long jogs.

There’s always going to be a compromise

in adaptations, unfortunately.

It does seem like you can do concurrent training,

as I mentioned before, if you allow anywhere

from four to six or ideally 24 hours between workouts.

As I mentioned in the previous episode,

if you want to know if you are recovered from a workout,

a great way to do that is to apply

the carbon dioxide tolerance test,

which is four breaths in and out,

inhale, exhale, inhale, exhale, inhale, exhale,

inhale, exhale, then a big inhale,

and then a slow controlled exhale.

If that slow controlled exhale is 60 seconds or longer,

it means that your parasympathetic,

your calming nervous system is under your control.

And it’s likely, I should say likely,

that systemically your whole nervous system has recovered

from whatever it is that you’ve been doing

and experiencing in life, including work and relationships.

If not, you might want to take a rest day, dare I say,

or Costello’s on his, what?

He’s 10 now, I think he’s on his 12,000th rest day.

Most people need, I should say,

one to two full rest days per week.

I know there are people who are going to say

that’s ridiculous and okay,

maybe you have amazing recovery abilities.

Also depends on training intensity.

Many people benefit from having one or two

full rest days per week, at least one.

Some people don’t need to.

But if you are not able to extend that exhale

on the carbon dioxide tolerance test

past 60 seconds or so, 45 seconds, 60 seconds,

chances are your so-called sympathetic nervous system,

your stress system is chronically elevated

and you’re not really putting the brake

on that system enough.

And that’s a subconscious thing.

There are ways that you can accelerate recovery,

but I would encourage you to listen

to the previous episode.

It’s timestamped for how to assess recovery.

So how often to program these things

will depend on the other things you’re doing.

I think it’s perfectly reasonable to do this type of training

with other types of training.

And I’ll talk about a variety of combinations of those

toward the end of the episode.

I do want to talk about how to deliver

more energy and oxygen.

These are tools that are extremely useful, I believe,

and that are grounded in physiology.

The three things I’d like to talk about

are how to breathe,

what to do immediately after training and hydration.

And I promise I will get back into programming

and sort of protocols,

but these are vitally important to your ability

to perform endurance work in particular.

And they are grounded in how neurons and blood

and oxygen and your heart work together.

So let’s first talk about breathing or respiration.

We breathe a couple of different ways,

but let’s just remind ourselves why we breathe.

We breathe to bring oxygen into our system

and we breathe to get rid of carbon dioxide.

And we need both oxygen and carbon dioxide

in order to utilize fuel and for our brain and body to work.

It’s not that oxygen is good and carbon dioxide is bad.

They have to be present in the appropriate ratios.

So one thing that is very clear

is our ability to deliver oxygen to working muscles

and to our brain is going to be important

for our ability to generate muscular effort,

especially of the kind I was talking about today,

but also weight training

and other forms of skill-based effort, et cetera,

and our ability to think.

If you’re holding your breath for too long,

if you’re breathing too much,

if you’re what they call over-breathing or under-breathing,

if you’re shallow breathing, if you’re mouth breathing,

these are all things that can really impede

mental and physical performance.

So let’s make it really simple.

And then I promise to do a future episode

all about respiration.

There are two main sources of air for your body

and it’s air coming in through your nose

and air coming in through your mouth.

In general, nasal breathing is better.

It scrubs the air of bacteria and viruses.

You have a microbiome in your nose that benefits.

There are a number of reasons.

It’s also just a more efficient system, believe it or not.

Even though it feels like you can gulp more air

with your mouth, getting good at nasal breathing is useful.

A gear system of the type that Brian McKenzie

and colleagues have developed,

I think is a good way to conceptualize this.

If you’re doing long duration work,

try and do it all nasal breathing.

If you have deviated septum,

it’s probably because you don’t nasal breathe enough.

Mouth breathing is something that many people suffer from.

You’re more prone to infections.

It’s not as efficient, et cetera.

There is a place for mouth breathing.

However, it’s usually if you need to do a strong exhale,

oftentimes you can discard more volume through the mouth

unless you’re very trained at nasal breathing.

So if you’re doing high intensity training,

a good way to conceptualize this is to exhale

on the max effort and then to inhale

on the less intense part.

So that might be as you’re generating the movement,

you know, in the concentric part of the movement,

you exhale, right?

Just like on a bat swing or something like that,

or, you know, fighters and martial artists

do this differently depending on how they were trained

and the different purposes,

but the kind of like, ah, or shh,

the kind of exhaling during the effort

and then inhaling on the portion of the repetition

that is not the highest effort portion.

Usually that’s the eccentric phase

of anything involving weights or rowing

and things of that sort.

So nasal breathing is great,

but as you increase the intensity of your endurance work,

you will need to incorporate the mouth.

So a gear system would look something like

first gear would be just nasal breathing,

or second gear would also be just nasal breathing,

but with more effort.

Third gear, again,

Power Speed Endurance has a lot more about this.

You can go to their website.

I think it’s a very intelligent way to conceptualize this.

As you go into more max effort,

then you’re going into third and fourth and fifth gear.

And at some point you’re not thinking about nose or mouth.

You’re just trying to hang on for dear life

and complete the work safely.

And that means breathe through

whatever orifice works for you.

So that’s one aspect, nose versus mouth.

The other aspect is whether or not you’re using your ribs,

the intercostal muscles are these muscles

that the Bruce Lee had these remarkable intercostal muscles

that allow you to lift the rib cage or the diaphragm,

which is a skeletal muscle that sits below the lungs.

Just to remind you, when you inhale, the diaphragm moves down

when you exhale, the diaphragm moves up.

Here’s something that most people don’t do

and would benefit tremendously from.

And I can say this because Andy Galpin’s lab

has done work on this,

exploring how warming up the intercostals

and the nerve to diaphragm pathways

before any kind of endurance work

or in the first few minutes of endurance work

can allow you to breathe more deeply

and to deliver more oxygen to the blood,

and excuse me, and to the muscles

and to be able to do more work more efficiently.

So what that involves is sometimes sitting,

sometimes standing,

and just really concentrating on two things.

We always hear about how we should diaphragmatic breathe.

And that means our belly moves out when we inhale.

So our stomach expands,

but also expanding the intercostals,

which means actually raising the ribs, chest breathing.

We’re all told that in yoga class,

don’t breathe with your chest this,

but actually that is warming up the intercostal muscles.

So this is also a great way to generate adrenaline

if you do it a little bit intensely.

So let’s say you’re feeling unmotivated to train.

I don’t particularly like doing endurance training

until I’m actually doing it.

So I use and benefit from having a practice

where I’ll just sit there and for about three minutes,

I’ll just breathe very deeply,

trying to raise my chest as much as I can

for maybe a minute,

and then expanding, contracting my diaphragm

and expanding my stomach outward when I inhale.

By the end of that,

you’re actually delivering more oxygen to your system.

My lab has looked at this in a totally different context.

Andy’s lab has looked at it

in the context of physical performance.

So warming up the breathing muscles should make sense

given that you now know that muscles and neurons

need glucose and they need oxygen in order to function.

And so that’s a great warmup.

You can also do this while walking

or while getting on the bike and starting to pedal,

really starting to think about

warming up the breathing system.

And then you can decide if you want to do pure nasal

or a combination of nasal and mouth breathing and so on.

So that’s something that we don’t often hear about.

The other one, the other tool rather

that I talked about in a previous episode,

I’ll just mention again,

is some people, when they do endurance type work,

they get a stitch in their side.

They feel like they’ve got a side cramp.

Very rarely is it actually a skeletal muscular cramp.

It’s oftentimes, it’s a referenced pain

of the phrenic nerve that innervates the liver.

So the phrenic nerve is responsible

for the movement of the diaphragm.

It is a very important system,

but it has a number of what we call collateral.

So it branches to other organs, runs over other organs.

Sometimes when we’re breathing shallow

and we are in physical motion

and we’re engaging in physical effort,

we’ll feel that side stitch and we think,

oh, I’ve got a cramp or maybe I’m dehydrated

or maybe I need to run with my hands over my head.

Excuse me.

Typically you can relieve that side cramp,

which isn’t a cramp at all, that side stitch

by doing the double inhale, exhale,

really breathing deeply

and then sneaking a little bit more air in.

That’s a double kind of firing

or what we call volley of action potential

sent from the phrenic nerve to the diaphragm,

which will also activate that collateral,

that branch literally of the nerve

that innervates the liver.

And then when you exhale,

you offload a bunch of carbon dioxide.

But if you repeat that a few times,

often, in fact, for me every time,

but often what’ll happen is that side stitch

will just naturally disappear.

It just means you’re not breathing properly.

The phrenic nerve is firing in a way

that’s kind of aggravating that referenced pain.

There’s nothing kind of voodoo or mysterious about this.

It just has to do with the way

that the different nerves travel in the body.

So as you set out on your run

or maybe you’re going to do some muscular endurance work

or high intensity work, warming up the intercostals,

warming up the diaphragm is good.

And there are exercises,

there is work that you can do to strengthen

the intercostals and to strengthen the diaphragm

during bouts of this kind of effort.

And I would say that one of the ways

that you can do that best is by really focusing

on getting the maximum diaphragmatic expansion

and chest lifting, what we’re all told now not to do.

Don’t chest breathe, belly breathe.

The intercostals are there for a reason

and they are perfectly good at filling your lungs.

They work best when they collaborate with your diaphragm.

But when you’re starting to fatigue,

to start to really inhale deeply

and try and really expand those

to deliver more oxygen to your system.

While we’re talking about delivering more oxygen

to your system, I want to share with you a useful tool

that will now make total sense mechanistically why it works,

which is oftentimes when we are on a long run

or in long duration bouts of effort,

we will hit the so-called wall, right?

We will bonk, I think they used to call it

or maybe do they still call it that Costello?

He’s asleep.

We bonk, we just, we think, no, we can’t continue.

It’s a curious thing as to whether or not that’s neural

or whether or not it’s fuel-based.

There’s certainly going to be a psychological

or motivational component.

But one way that you can reveal this kind of extra gear

or the capacity to push on is by understanding the way

that different muscle fibers use energy differently.

Remember the fast twitch phosphocreatine system

and the slow twitch system that relies mainly

on lipids and glucose.

Okay, well, even if you don’t remember all that,

if you’ve been running steadily for a long time

and you’re starting to fatigue

and you feel like it’s time to quit,

you may have not tapped into an alternative fuel source.

One thing that you can do

is you can actually increase your speed.

This is also true of work where you’re doing repetitions

with kettlebells or something.

You can start to increase your speed.

So run faster, pedal faster, row faster, swim faster,

not all out sprint, but in doing that,

you’re shifting the muscles and the nerves

over towards utilizing a separate fuel source

or a distinct fuel source.

Maybe the phosphocreatine system,

if it’s a quick bout of intense acceleration,

or maybe it’s a combination of lipids and carbohydrates

in your system that weren’t available to you prior.

Now, of course,

if you completely deplete your liver glycogen,

you completely deplete everything,

you’re only going to be running on stored fuel and fats

and eventually you’ll start metabolizing protein,

muscles themselves.

But this is a kind of a unique way to realize that,

oh, you weren’t out of energy at all.

You were just over-relying on one fuel source.

And this is the reason why,

especially elite athletes are starting to

both rely on carbohydrates.

So they’re doing the whole carb depletion,

then carb loading thing.

They’re loading up their liver and their muscles

with plenty of glycogen by eating pastas and rice

and stuff before races,

but they are also ingesting ketones during races,

during long bouts of effort,

because ketones can be a quick form of energy.

There’s no reason why you can’t use ketones

if they are taken, exogenous ketones,

and carbohydrate and in combination.

Remember the body is accustomed

to using multiple fuel sources, fatty acids, carbohydrates,

all these things.

It’s only in the kind of internet age that we think

in terms of, oh, well, you’re either keto

or you’re burning sugar or you’re fat adapted

or you’re fat fasting or fast fasting or fat fadding.

Costello woke up when I said fat fadding.

I’m not talking about you, Costello.

So the point is that your body is used

to using multiple fuel sources.

So if you’re kind of hitting that wall,

sometimes accelerating can actually allow you to tap

into a new fuel source or combination of fuel sources

just based on the way that muscles use fuel.

So that’s another tool.

The other thing that’s really important to think about

in terms of endurance type work is hydration.

And I think hydration is important

for all forms of physical work and exercise,

not just endurance.

The deal with hydration is that we’ve been taught

about hydration all wrong,

but let’s remember what neurons work on.

What do they use in order to fire?

Well, they certainly need water, right?

We need water in our system, I should say,

but remember they use electrolytes, sodium and potassium

to generate those action potentials

to actually get neurons to contract,

to be able, excuse me, muscles to contract

and for our brain to function and to be able to think.

Typically, we’re going to lose anywhere

from one to five pounds of water per hour of exercise.

And that’s going to vary tremendously.

It’s going to vary on weather.

It’s going to vary on intensity,

probably more like five pounds if it’s hot day

and you’re exercising very intensely.

So about one to five pounds per hour.

Now, you know how much you weigh.

So if you think about your weight in pounds,

once you lose about one to 4% of your body weight in water,

you’re going to experience about a 20 to 30% reduction

in work capacity, in your ability to generate effort

of any kind, strength, endurance, et cetera.

You are also going to experience a significant drop

in your ability to think and perform mental operations.

So hydration is key.

Now, many people have been told,

well, if you urinate and your urine is clear,

well, then you’re hydrated enough.

Sometimes that’s true.

Sometimes that’s not true.

Also, and this isn’t a topic I enjoy discussing,

but urine is a biological phenomenon.

It’s actually filtered blood.

Went to, every once in a while,

if there’s a kid and it’s a family friend, I’ll say,

did you know that your pee is actually filtered blood?

And they usually kind of go wide-eyed,

but then they go, oh, that’s kind of cool.

Like kids have this natural curiosity

about blood and pee and stuff

that’s not contaminated by our preconceived notions

of those things being gross.

Because urine being filtered blood

can give you some indication

as to whether or not you’re hydrated enough or not.

And in order to really assess that,

it’s not going to be sufficient to urinate

into another volume of water

and assess whether or not your urine

is very dark or very light.

It actually requires urinating into a small volume

and saying, well, is it darker or lighter than before?

It’s not something you really want to do most places.

The etiquette of most gyms and environments

is not suitable for that.

But one of the things that you can just do

is you can figure, well,

I’m going to lose one to five pounds of water per hour.

You can show up to exercise reasonably hydrated

with electrolytes.

So potassium, sodium, and magnesium are really key.

Yes, it’s true.

You can die from drinking too much water in particular

because it forces you,

if you drink too much water,

you’ll excrete too many electrolytes

and your brain will shut off.

You’ll actually, your heart will stop functioning properly.

So you don’t want to over-consume water

to the extreme either.

But there are a number of equations

that go into figuring out how much water you need

based on how intense your training, et cetera,

body size, et cetera.

Just remember, you burn, you lose, excuse me,

about one to five pounds of water per hour,

depending on how hot it is

and how intensely you’re exercising.

Once your body weight drops by one to 4%,

so you can just figure it,

well, if you lose five pounds per hour,

you exercise for two hours,

let’s say you’re about 200 pounds, that’s about 10%, okay?

Well, you want to replace that before, very quickly,

or you want to replace that all along

before you start experiencing

this massive 20 to 30% reduction

in work capacity of muscles and the brain.

A simple formula, what I call the Galpin equation,

hereafter referred to as the Galpin equation,

is a formula that gets you close to the exact amount

that you would want that Dr. Andy Galpin came up with,

which is your body weight in pounds

divided by the number 30.

And that is how many ounces you should drink

for every 15 minutes of exercise.

So once again, the Galpin equation,

your body weight in pounds divided by 30,

that’s the amount of fluid to drink in ounces, right?

Every 15 minutes of exercise.

Now, if you are sweating a lot, you may need more, okay?

If you’re already very well hydrated, you may need less,

but that’s a good rule of thumb to begin

and to start to understand the relationship

between hydration and performance.

There is a phenomenon in which gastric emptying,

the ability to move stuff out of your gut,

including water and electrolytes,

out of your gut and into the bloodstream

and for delivery to the tissues of your body for effort

is hindered when you get above 70% of your VO2 max.

In other words, when you’re doing high intensity training,

sometimes people experience that ingesting water

during intense training is difficult.

It is something that can be actually trained up.

It’s a matter of learning to kind of relax

your abdominal muscles.

And there’s some other aspects of adaptation

that will allow you to drink during higher intensity work.

As Galpin says, don’t try and ingest fluids

when you’re working out or competing at higher

than 70% of VO2 max.

If you’ve never done it before,

you want to train up this capacity.

People can learn how to consume fluids during a race

or consume fluids during bouts of exercise

that are very intense.

And a lot of people don’t want to do that

because they don’t want to have to stop to urinate, et cetera.

But given the crucial role of hydration

for muscular performance and for brain performance,

it seems that if you’re going to be doing a lot

of high intensity interval training

of the various kinds I talked about today

or high intensity training of any kind,

that hydration is key and learning,

or in other words, getting your system to adapt

to ingesting fluids in the middle of these workouts

is something that seems beneficial, at least to me,

in terms of the trade-off between being dehydrated

and the somewhat discomfort of maybe drinking some fluid.

So you sip small amounts of fluid initially,

and then you’re able to take bigger and bigger gulps

as time goes on.

And pretty soon you’re able to drink mid-set,

or excuse me, not mid-set, please don’t do that,

between sets in your workout

or while you’re still breathing hard after a mile repeat

or something of that sort without much disruption

or any at all to your performance.

Last episode, we talked about how to assess recovery

and things that you might want to do to improve recovery,

how exposure to ice baths and cold showers

can reduce inflammation, which can be great for recovery.

But can inhibit some of the adaptations

for strength and hypertrophy

because inflammation isn’t good or bad.

Inflammation isn’t like a nice person or a mean person,

it’s both.

It’s a great thing for stimulating adaptations,

but you don’t want it around too long.

And so we suggested that you not do ice baths

within probably six hours of any training

where the goal was hypertrophy or strength training.

There is some evidence that getting yourself

into an ice bath or cold shower after endurance training

can actually improve the mitochondrial aspects

of endurance exercise,

that you can get improvements in mitochondrial density

and you can get improvements in mitochondrial respiration

by doing that afterwards

and that it can facilitate recovery.

That’s still a bit of a controversial area.

I do think that what I mentioned earlier,

that waiting at least six hours

and probably more like 24 hours between workouts

is a good idea,

that getting at least one full day of rest each week,

for some people that’ll be two.

I have to say, I’m one of these people

that after two days of absolutely no exercise,

I do perform better consistently

across all aspects of physical performance

and mentally I feel better as well,

even though I loathe to take those days off

unless I’m really exhausted,

it does seem to help my training.

Some people can train seven days a week and they’re fine.

I think it just is, there’s a lot of individual variation.

You want to work on sleep and maximizing sleep for recovery,

nutrition, of course, as well.

I talked about sleep in the first four episodes

of the podcast.

If you have trouble with sleep,

definitely check out those episodes.

It’s very clear and a number of sports teams,

even some folks that I work with

and Andy Galpin and others are starting to incorporate

a what’s called a parasympathetic down regulation

after training of any kind as a way to accelerate recovery

and enable you to do more work.

In other words, get back to workout sooner.

What is parasympathetic down regulation?

It means finishing your training

and instead of just hopping on the phone

or hopping into your car

and heading off to take five minutes minimum,

maybe ideally more like 10 or 20,

but for sake of time, five minutes minimum

and doing just some slow, pure nasal,

long exhale devoted breathing

or lying down and just kind of zoning out.

That it seems can accelerate recovery

and allow you to get back into other types of work,

mental work or physical work more quickly,

which makes total sense

because remember your nervous system

and recovery and work is a local phenomenon.

Which muscles were you using?

Were you using your glutes, your hams and your back

or were you using your shoulders, et cetera,

but it’s also a systemic thing.

It’s also about those neurons in the locus coeruleus

that are releasing epinephrine.

You want to quiet all that down after training.

You want to really just zone out.

Think Costello, channel your inner Costello

and just mellow out for five to 20 minutes

and then move into the rest of your day.

Five minutes should be manageable,

even if it’s just sitting in the car with your eyes closed,

doing that down regulation breathing.

I think you’ll see big benefits

in terms of allowing yourself to come back sooner,

do more work over time

and just perform and feel better generally,

as well as be able to think about other things

besides the just how much the previous workout

kind of beat you up.

A couple more things I think are going to be useful

and I do want to just pack these in

because we are closing out the month

on physical performance

and that’s about programming

and about pacing and the kind of mental aspects

of endurance.

So let’s start with pacing and mental aspects of endurance.

I learned from a friend and colleague here at the podcast

that who’s very active in triathlon and marathon

and other knows a lot about that whole world

and the competitive landscape there,

that pacing and literally physical pacers

of a laser on the ground

or visualizing or having a pace car

or a pace runner in front

is actually not allowed in many competitions.

And if those are present,

doesn’t allow the race times to qualify

as legitimate record holding times.

And that’s very interesting to me

because what we know is that the visual system

has this capacity to switch back and forth

between what we call panoramic vision

where we’re not really focused on anything.

Things are just flowing past us

or our eyes are just kind of zoned out.

So I can do this right now and you won’t be able to tell,

but I’m looking at the corners of the room.

I see Costello down there on the floor.

I see my podcast team here

and I can also see the microphone.

I can see myself in this environment.

That’s panoramic vision.

Whereas if I draw my eyes to one location,

like right there in the center of the camera,

it’s what’s called a vergence eye movement.

So I’m contracting my visual window.

The contraction of the visual window when that’s done

is the same thing that would happen

if I was tracking say a pace car or a pace runner

or a laser on the ground.

The mere bringing our eyes together

to what we call a vergence point

has the impact of triggering the activation

of neural circuits in the thalamus,

things like zona and serta,

if you really want to know what their names are,

of these brain areas,

as well as in the brainstem that activate

the so-called alertness system,

things like locus coeruleus.

Whereas panoramic vision tends to bring us

into states of relaxation.

You can actually leverage this during your runs.

Let’s say you’re out for a long run

or you’re swimming or you’re cycling.

This is probably easiest to imagine out of the water,

but you probably do in the water as well.

If you focus your attention on a landmark

that you’re going to run to,

you’ll find that it’s much easier

than if you don’t actually have a set milestone

or landmark that you’re going to run to.

However, if you were to continue that repeatedly,

just going milestone after milestone after milestone,

you would feel more mentally fatigued

and you would actually be able

to generate less work overall.

One thing that can be useful is focusing on a milestone,

running to that milestone or biking,

whatever it is the activity happens to be,

and then dilating your field of view to relax the system

and then continuing again.

So it’s this kind of active contraction

or of the visual window

and then dilation of the visual window.

Contraction of the visual window

allows you to generate more effort,

but there’s a cost to doing that

because neurons consume energy

and now you know how they do that.

Whereas dilation allows you

to essentially be more efficient, right?

Now, pacing is not allowed or having a pacer,

a visual pacer, because it does allow you

to access systems in the brain and body

that allow you to create more energy, more effort.

And so I find it interesting

that I think in a kind of subconscious genius,

the race officials and the governing bodies

of these races have said, okay, sure,

having a pacer there or someone in front,

you can draft off of them.

There’s actually a kind of a aerodynamic effect

of having someone in front of you

that makes it easier to run in the wake

of their airstream, so to speak.

Same is true in cycling.

This is why the cycling teams

are so good at maneuvering in packs in very specific ways.

You can go faster with less effort

if you’re drafting as it’s called behind somebody.

But as well, where you place your vision

will allow you to generate more effort.

And so it’s interesting that they’ve taken out

this kind of, if you will, performance enhancing tool.

I imagine, and I have to imagine,

it’s the appropriate word here,

that good runners, good cyclists have the ability

to create a kind of pacer in their mind’s eye.

I have to imagine that they’re not just completely

allowing their attention to drift,

although they do that when they want to be

in highly efficient mode,

generating effort without having to tax

their mental capacity.

And remember, mental capacity is neural energy

and consumes glucose, energy that they could devote

to the functioning of their body,

but that when needed, that they can focus their energy in

and actually kind of chase a mental pacer

or pick milestones.

So this is a mental game that you can play as well.

It’s a little bit hard to do in the context

of weightlifting in the gym.

It’s more of a moving through space kind of thing,

but some people do this by counting reps, et cetera.

I think it’s especially suitable for endurance type

of exercise, especially done outside.

One of the reasons I hate running on a treadmill

is it just feels like it’s never ending.

And I’ve never tried one of these Peloton things.

I try and avoid looking at screens

as much as I possibly can.

But if you try this next time you’re out for a run

or a swim, what you’ll find is that you have a capacity

to engage a system of higher energy output

when you focus your eyes on a particular location,

but you want to use that judiciously

because your goal, of course, is to become efficient

at moving through space over time

and not taxing your brain and body to the point

where you arrive at the end of that,

unless it’s race day, just completely tapped out.

So that’s a kind of interesting aspect of running.

If you’re a fan of running, which I am,

and you get the chance to look at any of the documentaries

or docudramas made about, excuse me,

about Steve Prefontaine, it was clear that he was mostly

in a battle with himself,

but that he was also a highly competitive individual.

And you’ll see this in some of his races.

I do encourage you to look some of those up on YouTube

or see the docudramas, they’re quite good,

where he ran the, essentially was 12 laps on a track.

It’s essentially the five, it is the 5,000 meter race,

which is essentially three miles.

And he essentially tried to sprint the whole thing,

which is ridiculous.

Actually knowing what you know today,

you’ll realize that Steve Prefontaine basically

was pulling from strength, speed, power,

muscular endurance, long duration effort,

high intensity aerobic and aerobic,

is he sort of tried to maximize every fuel system.

And you’ll see that in the races that he runs,

but that when runners are nearing the final laps,

the so-called bell lap of a race,

they’ll often look to one another to see where somebody is,

obviously to assess their progress

and how close somebody is.

But when somebody gets passed,

oftentimes you’ll see someone access this mysterious kick,

this ability to tap into some additional gear

that allows them to run forward or faster

when they themselves actually thought

that they were maxed out.

So someone could be running for the finish line,

they’re convinced they’re going to win,

they’re going max effort,

or at least they perceive max effort, someone passes them.

And all of a sudden max effort has changed

because of that visual target,

they are able to access higher levels of speed and output

and effort and performance.

They don’t always catch up to that person and win,

but having a target, a milestone is a powerful way

that we can generate more force and energy in anything.

And the visual system is the way

that we bring those milestones into our brain,

which then brings about epinephrine,

which brings about neural firing,

which allows us to access whatever resources

happen to be available to us.

So I find this fascinating because people often wonder like,

where does the kick come from?

Where is this kind of gift of an additional gear?

Where is that deeper resource?

And we often express it and talk about it

in kind of psychological terms like heart or willpower,

or that something kind of got transplanted into us

or descended into us.

And not to remove any of the spiritual aspects of sport

or running or effort or the human heart,

but it’s very clear that the nervous system,

when it has a specific visual target,

can generate the sorts of intense effort

that it couldn’t otherwise.

And it sometimes even comes as a surprise

to the person generating the effort.

I promised that I would talk about programming,

meaning when and how many times a week

to do the various workouts related to endurance

and how to merge those with other types of exercise

that you might be doing for strength or yoga

or other things that you might be doing like work

and other things unrelated to exercise.

Since that’s a vast space with many different parameters

and you all have different lives and lifestyles

and backgrounds with fitness, et cetera,

what I’m going to do is I’m going to put

three different levels, if you will,

or protocols that one could adopt

in a link on the show notes or in the caption on YouTube.

If you click on that link,

you’ll be able to see three possible combinations

of endurance work, strength and hypertrophy work,

or endurance work, flexibility and hypertrophy work

that are grounded in many of the major publications

that Dr. Andy Galpin and colleagues

and other people have described,

including this review that’s also linked there

on concurrent training and how one can use

concurrent training, meaning training for endurance,

training for strength, training for hypertrophy,

training for all these different things

without having to train constantly every day,

twice a day, et cetera.

So if you are interested in taking the protocols

that you learned about in this episode

and in previous episodes and combining those,

we’ve placed them there for you

as a completely zero cost resource.

Please understand they are not wholly,

Costello agrees, they are not wholly.

There will be variation in terms of what people can tolerate

and what they have time for,

but I think they’ll serve as a useful guideline

in getting started or in continuing with

and expanding on existing endurance work,

strength work, hypertrophy work, and so forth.

Just really quickly,

we didn’t talk about supplements much today.

In the previous episodes,

I talked about the phosphocreatine system

and supplementing with creatine,

talked about beta alanine for kind of moderate duration work.

You know, really the only things that have been shown

to really improve endurance work

across the four varieties of endurance work

I described today,

they have essentially two forms.

One are stimulants, so things like caffeine

will definitely improve endurance work and power output.

There’s a little bit of evidence that caffeine intake

can actually inhibit the function of the creatine system,

but it’s just one study, but that’s interesting.

If you want to read that study,

you can put caffeine into

and it will take you to that study.

Many people get sore after workouts,

in particular workouts that involve

a lot of eccentric loading

or workouts that are very novel

where they’ve kind of pushed it

instead of moving gradually, as I suggest,

into say high intensity anaerobic endurance work

of three sets of 20 seconds on 100 second rest.

Maybe you get overambitious and you do eight sets,

in which case you are extremely sore.

Certain forms of magnesium,

in particular magnesium malate, M-A-L-A-T-E,

have been shown to be useful for removing

or reducing the amount of delayed onset muscle soreness.

That form of magnesium is distinctly different

than the sorts of magnesium

that are good for getting us into sleep,

things like magnesium threonate and biglycinate.

And then there’s this whole thing about beet powder

and beet juices and things that increase nitric oxide

and allow for more vasodilation

and therefore delivery of blood to muscle and neurons

and other tissues for long bouts of endurance work.

Some people like beet juice and the related compounds

that increase arginine and vasodilation.

Some people don’t.

Some people don’t feel good when they take those.

Some people also don’t feel good when they take beta-alanine

because it can give them this feeling

of kind of like itchy, creepy crawlies under the skin,

kind of the niacin phenomenon, the niacin flush.

Some people don’t mind that

or some people don’t experience that.

So when it comes to supplementation,

there’s a lot of variety,

but magnesium malate has been shown to reduce soreness,

so sometimes that’s good.

Cold and hot contrast therapy for soreness,

things of that sort.

But in general, we focused mainly today

on behavioral tools.

You’ll notice that all of the tools are accessible

without the need for lots of equipment.

So I didn’t say you need a rower or you need a kettlebell,

though those will work.

And I hope I was able to illustrate for you

that endurance isn’t just one thing.

It’s not just the ability to go for long bouts of exercise

of different kinds,

that there’s also this mental component

because of the way that neurons work.

And also that there are these different forms of endurance,

of muscular endurance,

where you’re going to fail because of the muscles

and muscle energy utilization

and the nerves that innervate those muscles locally,

not because of a failure to bring in oxygen or blood.

Whereas long duration effort,

it’s going to be more about being below your VO2 max

and your ability to be efficient for long bouts

of more than 12 minutes of exercise.

One set, as they say, of 12 minutes to maybe several hours.

I should just mention with long duration type work,

you could even imagine raking in the yard or mowing a lawn,

depending on how big that lawn is.

I used to have a job when I was a kid mowing lawns.

And I’ll tell you,

we didn’t have many neighbors with very big lawns,

but there are a few of them felt huge

because they were really convoluted.

And if you’re pushing that mower,

and these were the old fashioned mowers,

not electric mowers, it’s work.

That’s also of the sort

that we call long duration endurance work.

High intensity training will tap into yet other fuel sources

and mechanisms as we learn today.

So if you are enjoying this podcast

and you’re finding the information useful,

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Thank you for your interest in science.

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