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
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I’ve been taking Athletic Greens since 2012,
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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
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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
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with your immune system, with your brain to regulate mood,
and essentially with every biological system
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With Athletic Greens, I get the vitamins I need,
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There are a ton of data now
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Even if we’re getting a lot of sunshine,
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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,
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I’ve talked many times before on this podcast
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for nerve cell function, neuron function,
as well as the function of all the cells
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If we have sodium, magnesium, and potassium
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If the electrolytes are not present,
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our mood is off, hormone systems go off,
our ability to get into physical action,
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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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Today’s episode of the Huberman Lab Podcast
is our fourth and final episode in this month,
which is all about skills and athletic performance.
Now, in a previous episode,
we talked about science-based,
in particular neuroscience-based tools
for accelerating fat loss.
Previous to that,
we talked about ways to improve skill learning,
which also included things like music and piano playing,
not just athletic performance.
And we’ve also been exploring other aspects
of physical performance throughout the entire month.
Today, I want to talk about something
that is vitally important
for not just athletic performance,
but for your entire life and indeed for your longevity,
and that’s muscle.
Now, many of you, when you hear the word muscle,
think muscle growth and building big muscles.
And while we will touch on muscle hypertrophy,
muscle growth today,
and science-based protocols to enhance hypertrophy,
we will mainly be talking about muscle
as it relates to the nervous system.
And I can’t emphasize this enough.
The whole reason why you have a brain
is so that you can move.
And one of the things that’s exquisite
and fantastic about the human brain
is that it can direct all sorts
of different kinds of movement,
different speeds of movement,
movement of different durations.
We can train our musculature
to lift heavier and heavier objects,
or we can train our musculature
to take us further and further, so-called endurance.
We can also build smoothness of movement, excuse me,
smoothness of movement,
as well as speed of movement, suppleness of movement.
All of that is governed by the relationship
between the nervous system, neurons,
and their connections to muscle.
So when you hear the science of muscle
and muscle hypertrophy,
you might think, oh, well,
I’m not interested in building muscle,
but muscle does many critical things.
It’s important for movement.
It’s important for metabolism.
The more muscle you have,
and not just muscle size,
but the quality of muscle, that’s a real thing,
the higher your metabolism is,
and indeed the healthier you are.
It turns out that jumping ability
and ability to stand up quickly
and to get up off the floor quickly
is one of the most predictive markers of aging
and biological aging, and no surprise,
that is governed by the brain to muscle connection.
In addition, muscle and musculature is vital for posture,
and we don’t talk about posture enough.
We all have been told we need to sit up straight
or stand up straight,
but posture is vitally important
for how the rest of our body works.
It’s vital to how we breathe.
It’s actually even vital to how alert or sleepy we are.
So we’re going to talk about the musculature for posture.
We also are going to talk about muscle
as it relates to aesthetic things.
Now, these are all linked.
Muscle for metabolism, movement, posture, and aesthetics,
of course, are linked, right?
As our posture changes, our aesthetic changes.
As our posture and aesthetic changes, how we move changes.
And as we improve muscle quality,
whether or not that’s increasing muscle size or not,
that changes the way that our entire system,
not just our nervous system and our muscular system,
but our immune system and the other organs of the body work.
So today, as always,
we’re going to talk a little bit of mechanism.
I’m going to explain how neurons control muscle,
and then we’re going to look at muscle metabolism,
how muscle uses energy.
I promise to make all of this very simple.
I’m actually going to keep it very brief,
probably about 10 minutes total.
And by the end of that 10 minutes,
you will understand a lot about the neuromuscular connection,
how your brain and nervous system control your muscle
and how those muscles work.
Then we are going to talk about how muscles use energy
and can change how they use energy
for sake of getting stronger.
If you like for also increasing the size,
so-called hypertrophy of muscle,
and for improving endurance,
as well as for improving posture
and how you move generally.
We will touch on some nutritional themes
and how that relates to muscle in particular,
a specific amino acid that if it’s available
in your bloodstream frequently enough
and at sufficient levels can help you build
and improve the quality of muscle.
And we’ll talk about specific exercise regimes
as well as of course, supplementation
and things that can enhance
neuromuscular performance overall.
We are also going to talk about recovery.
Recovery as everybody knows is when things improve.
That’s when neurons get better at controlling muscle.
That’s when muscle grows.
That’s when muscle gets more flexible.
None of that actually happens during training.
It happens after training.
And there is a lot of confusion
about how to optimize recovery
and how to measure whether or not you are recovered
and ready to come back in
for another neuromuscular training session.
So we’ll talk about that as well.
Today is going to have a lot of protocols
and you’re going to come away with a lot of understanding
about how you move, how you work
and these incredible organs
that we call the nervous system and the musculature,
the so-called neuromuscular system.
Before we dive into today’s topic,
I want to just take about three minutes
and cover some essential summary of the previous episode.
In the previous episode, we talked about fat loss,
talked about shiver-induced fat loss.
We talked about NEAT, non-exercise activity thermogenesis
for increasing caloric burn and fat oxidation.
And we talked about how to use cold
specifically to enhance fat loss.
I described a protocol
involving getting into cold of some sort,
whether or not it’s ice bath, cold shower,
some form of cold, it could even be a river or an ocean
if you have access to that,
and inducing shiver and then getting out,
not crossing your arms or huddling,
but allowing that cold to evaporate off you
and continuing to shiver
and then getting back into the colder environment
of water or stream or shower, et cetera.
All of that is described
in a beautifully illustrated protocol
that I didn’t illustrate,
that’s why it’s beautifully illustrated
They’ve made that protocol for you
and they’ve made it available free of charge for you.
So there’s no obligation there of any kind financially.
You can go to thecoldplunge.com.
There’s a little tab that says protocols
and you can download that protocol.
Someone there, I don’t know who exactly illustrated it
and you can come away with a PDF
of what I described in the previous episode.
So I just want to make sure
that you’re aware of that resource.
The other announcement I’d like to make
is that many of you have asked
how you can help support the podcast
and there’s a very straightforward,
zero cost way to do that
and that’s to subscribe to our YouTube channel.
So if you go to YouTube,
if you’re not already there watching this now,
hit the subscribe button.
That helps us tremendously
to get the word out more broadly about the podcast
and we thank you for your support.
Most people, when they hear the word muscle,
they just think about strength.
But of course, muscles are involved
in everything that we do.
They are involved in speaking,
they’re involved in sitting and standing up,
they’re involved in lifting objects, including ourselves.
They are absolutely essential
for maintaining how we breathe.
They’re absolutely essential for ambulation, for moving
and for skills of any kind.
So when we think about muscle,
we don’t just want to think about muscle,
the meat that is muscle,
but what controls that muscle.
And no surprise,
what controls muscle is the nervous system.
The nervous system does that
through three main nodes of control, areas of control.
And I’ve talked about these before on a previous podcast,
so I will keep this very brief.
Basically, we have upper motor neurons in our motor cortex.
So those are in our skull
and those are involved in deliberate movement.
So if I decide that I’m going to pick my pen up
and put it down, which is what I’m doing right now,
my upper motor neurons were involved
in generating that movement.
Those upper motor neurons send signals
down to my spinal cord,
where there are two categories of neurons.
One are the lower motor neurons
and those lower motor neurons send little wires
that we call axons out to our muscles
and cause those muscles to contract.
They do that by dumping chemicals onto the muscle.
In fact, the chemical is acetylcholine.
I’ve talked before about acetylcholine in the brain,
which is vitally important for focus
and actually can gate neuroplasticity,
the brain’s ability to change in response to experience.
But in the neuromuscular system,
acetylcholine released from motor neurons is the way,
the only way that muscles can contract.
Now there’s another category of neurons in the spinal cord
called central pattern generators or CPGs.
And those are involved in rhythmic movements.
Anytime we’re walking or doing something
where we don’t have to think about it to do it deliberately,
it’s just happening reflexively,
that central pattern generators and motor neurons.
Anytime we’re doing something deliberately,
that the top-down control, as we call it,
from the upper motor neurons comes in
and takes control of that system.
So it’s really simple.
You’ve only got three ingredients.
You got the upper motor neurons, the lower motor neurons,
and for rhythmic movements that are reflexive,
you’ve also got the central pattern generators.
So it’s a terrifically simple system at that level.
But what we’re going to focus on today
is how that system can control muscle
in ways that make that system better.
Now, when I say better, I want to be very specific.
If your goal is to build larger muscles,
there’s a way to use your nervous system
to trigger hypertrophy,
to increase the size of those muscles.
And it is indeed controlled by the nervous system.
So you can forget the idea that the muscles have memory
or that muscles grow in response to something
that’s just happening within the muscle.
It’s the nerve to muscle connection
that actually creates hypertrophy.
I’ll talk exactly about how to optimize that process.
In addition, if you want to improve endurance
or improve flexibility or suppleness or explosiveness,
that is all accomplished by the way
that the nervous system engages muscles specifically.
And so what that means is we have to ask ourselves,
are we going to take control of the upper motor neurons,
the central pattern generators,
or the lower motor neurons or all three
in order to get to some end point
of how the nervous system controls muscle.
So neurophysiology 101,
I’ll give you one piece of history
because it’s important to know.
Sherrington, who won the Nobel Prize,
called movement the final common path.
Why did he say that?
Well, the whole reason for having a nervous system,
the whole reason for having a brain
is so that we can control our movements
in very dedicated ways.
That is one of the reasons,
perhaps the predominant reason
why the human brain is so large.
You might think, oh, it’s so large for thinking
and for creativity.
Ah, no, when you look at the amount of real estate
in the brain that’s devoted to different aspects of life,
it’s mainly vision, our ability to see, and movement,
our ability to engage in lots of different kinds
of movements, slow movements, fast movements,
explosive, et cetera.
Other animals don’t have that ability
because they don’t have the mental real estate.
They don’t have the neural real estate in their brain.
They have neuromuscular junctions.
They have central pattern generators.
What they don’t have are these incredible
upper motor neurons that can direct activity
of the muscles in very specific ways.
So we can all feel blessed that we have this system.
And today I’m going to teach you how to use that system
toward particular end points.
So if we decide that we are going to direct our muscles
in some particular movement of any kind,
whether or not it’s a weightlifting exercise
or whether or not it’s a yoga movement
or simply picking up and putting down a pen,
we are engaging flexors and extensors.
And our body is covered with flexors
and extensors all over.
So for instance, our bicep is a flexor
and our tricep is an extensor.
Those are what are called antagonistic muscles.
They move the limbs in opposite directions.
So if you bring your wrist closer to your shoulder,
that’s flexion using your bicep.
If you move your wrist further away from your shoulder,
that’s extension using your tricep.
And without getting into a lot of detail,
the way that the nerves and brain are wired up to muscle
make it such that when a flexor is activated,
when the nerve dumps chemical acetylcholine
onto the muscle to activate the biceps,
the triceps is inhibited.
It’s prevented from engaging.
There are ways to bypass this,
but that’s the typical mode of action.
The converse is also true.
When our tricep is inactivated, okay?
When we move our wrist away from our shoulder,
our bicep is inhibited.
And we have flexors like our abdominal muscles
and we have extensors in our lower back.
Many of you probably know this,
but some of you probably don’t that your spine has flexors
to move basically your chin toward your waist.
And it has, those are your abdominal muscles among others.
And you have extensors that move your chin basically back,
like looking up toward the ceiling,
and those are your extensors.
You have other muscles that are stabilizing muscles
and things of that sort,
but those movements of flexion and extension
and the fact that they are what we call
reciprocally innervated or mutual inhibition,
you hear different language around this,
is characteristic of most of our limb movements, okay?
So hamstring and quadricep,
the hamstring brings the ankle closer
back towards the glutes.
Basically it’s lifting your heel up, right?
Which is almost always done toward the back.
Whereas your quadriceps is the extensor
opposite to the hamstrings.
So you get the idea.
So there’s flexors and extensors
and it’s the neurons that control those flexors
and extensors that allow us to move in particular ways.
So now you have heard neuromuscular physiology
in its simplest form,
but I do want this to be accessible.
I want to get just briefly,
just briefly into some of the underlying metabolism
of how muscles use and create energy.
Because in doing that,
we will be in a great position to understand
all the tools that follow
about how to optimize the neuromuscular system
for your particular goals.
So in the previous episode about fat loss,
we talked about lipolysis,
the breakdown of fat into fatty acids
so it can be used as fuel.
And it ended in a step where we got ATP,
which is the bottleneck and final common path
for all energy producing functions in the body.
There are other ways,
but basically ATP is the key element there.
Now with muscles, they don’t function on fats normally.
What they are going to function on,
their ability to move and their ability to do things
and allow us to move in any way that we want to
is based on a process of glycolysis.
The breakdown of things like glycogen
and glucose into energy.
And it’s a very simple process.
You don’t have to know any chemistry.
So if I say the words carbon or hydrogen
or something like that, don’t freak out.
You don’t have to understand any chemistry.
But basically what happens is you’ve got this
available sugar resource that’s stored in muscle.
And that’s glucose.
And that glucose has six carbons
and six waters basically.
That can be broken down
into two sets of three carbons, all right?
So basically you take glucose and you break it
into these two little batches of carbons
that we call pyruvates.
So six divided by two is three.
So you get three and three pyruvates.
And that generates a little bit of ATP of energy,
but just a little bit.
Now, if there’s oxygen available, okay?
If there’s sufficient oxygen there,
what can happen is that pyruvate
can be brought to the mitochondria
and through a whole set of things
that you probably don’t want to hear about right now,
like the electron transport chain and citric acid cycle.
What happens is it’s broken down
and you get 28 to 30 ATP, which is a lot of ATP.
So the only things you need to know,
the only things you need to know about this process
is that glucose and glycogen
are broken down into pyruvate.
You get a little bit of energy from that.
And when I say energy, I mean the ability to move.
It’s fuel, it literally just gets burned up.
But if there’s oxygen available, and that’s key,
then within the mitochondria,
you can create 28 to 30 ATP, which is a lot of ATP.
Now, what does this mean?
This means that movement of muscle
is metabolically expensive.
And indeed, compared to other tissues,
compared to fat, compared to bone,
compared to almost all other tissues except brain tissue,
muscle is the most metabolically demanding,
which is why people who have more muscle
relative to adipose tissue to fat,
they can eat more and they’re more of a furnace.
They just kind of burn that up, okay?
So even if you didn’t understand anything that I just said,
what you probably did hear and that I hope you heard
is that if you have oxygen around,
you can create energy from this fuel source
that we call glycogen and glucose.
But what if there isn’t oxygen around?
And what is that like?
Well, you’ve experienced that.
I’m not talking about oxygen in the environment.
I’m talking about oxygen in the muscle.
So if you’ve ever carried a box while moving
or you were carrying heavy groceries to the car
or you were exercising particularly hard
and you felt the burn, well, that burning,
which most people think is lactic acid,
is actually a process by which pyruvate,
which as I said before,
normally could be converted into ATP if there’s oxygen.
Well, if there’s not enough oxygen
because that muscle is working too hard or too long,
what ends up happening is that a hydrogen molecule
comes in there and you get something called lactate.
So believe it or not, humans don’t make lactic acid.
That’s another species.
We make lactate and we think,
and we hear that lactate is bad.
We need to buffer the burn or avoid the burn,
that lactic acid and lactate are what prevent us
for performing as well as we ought to be able to
or for going as far as we possibly could
in an endurance event.
That’s not true at all.
Lactate has three functions,
all of which are really interesting and really important.
First of all, it’s a buffer against acidity.
You don’t want muscle to get too acidic
because it can’t function.
You don’t want any body tissue to get too acidic.
So that burn that you feel is acidity in that environment.
That and lactate, what most people call lactic acid,
but again, we don’t make lactic acid.
Lactate is there to buffer that,
to reduce the amount of burn.
So most people have this exactly backwards.
So when you feel that burn, that is not lactic acid.
That is lactate that’s present to suppress the burn,
to suppress acidity.
It’s also a fuel.
When you feel that burn,
lactate is shuttled to those areas of the muscle.
And there’s an actual fuel burning process
where in the absence of oxygen,
you can continue to generate muscular contractions.
Now this is informative because it also tells us
that that burning, that acidity that we feel
can inhibit the way that our muscles work,
but that lactate comes in
and allows our muscles to continue to function.
So we’ll talk a little bit more
about what this whole lactate thing and the burn means,
but it’s a really important process.
And it’s amazing to me that most people understand it
in exactly the incorrect way.
They think, oh, lactic acid is bad and the burn is bad.
No, it reveals a number of really important things
are going on with this vital molecule lactate,
which can reduce acidity, reduce the burn,
as well as act as a fuel.
Now here’s where it gets really, really cool.
And if you don’t have enough of an incentive to exercise
based on all the information out there
about how it’ll make you live longer
and make your heart better, et cetera,
here’s a reason that regardless
of what kind of exercise you do,
if it’s weight training or running or cycling or swimming,
that every once in a while, about 10% of the time,
you should exercise to the point of intensity
where you start to feel that so-called burn, right?
The reason for that is that lactate shows up
to the site of the burn, so to speak,
and it acts as a hormonal signal
for other organs of the body in a very positive way, okay?
As you may recall from a very early episode
of the Huberman Lab podcast,
I talked about what a hormone is and how it works.
We have lots of different kinds of hormones,
but hormones are chemicals that are released
in one location in the body and travel have effects
on lots of other organs of the body.
So when I say that lactate acts as a hormonal signal,
what I mean is that it’s in a position to influence tissues
that are outside of the muscle.
And basically, it can send signals to the heart,
to the liver, and to the brain,
and it can have effects on the heart, the liver,
and the brain that are very positive, okay?
So just to zoom out for a second,
I promise we won’t get any more technical than this.
We will get into tools and protocols
that are really straightforward,
but what I’m telling you is that if you feel a burn
from a particular exercise or movement,
that burn is going to be buffered
by this molecule we call lactate.
Lactate will then provide additional fuel
for additional work, so this is a good incentive,
provided you can do it safely
to quote-unquote work through the burn.
That burn acts as a beacon to the lactate,
which comes in and allows you to do more work.
It’s not a signal to stop necessarily.
I mean, stop if you’re doing something unsafe,
but it’s a signal that lactate should come in
and allow you to continue to do work,
and it can act as a hormonal signal.
Lactate can then travel to the heart
and to the liver and to the brain
and can enhance their function in positive ways,
not just in those moments,
but in the period of time that follows.
So many people are curious about how they can exercise
to make their brain better.
That’s one of the most common questions I get.
What I’m telling you is that provided you can do it safely,
by engaging the so-called burn,
which is a different threshold for everybody, right?
Your hill run will be different than my hill run
to generate the burn,
but provided you can do that for about 10%
of your workouts or of an individual workout
or activity of any kind,
you are generating the activity
of this lactate-based hormonal signal
that can improve the function of neurons.
And it does that, if you want to know,
for the aficionados, by improving the function
of another cell type called the astrocytes,
which are a glial cell type, okay?
Which are very involved in clearance of debris
from the brain.
They’re involved in the formation of synapses,
connections between neurons in the brain.
So put simply, if you’re an exerciser,
if you’re doing movement of any kind,
and you’re interested in allocating some of that movement
toward enhancing brain, heart, and liver health,
there is a nice set of scientific data
that points to the fact that getting lactate
shuttled to the muscles by engaging this burning sensation
is advantageous for the health of those other tissues.
So, as I mentioned, that burn is present
from lack of oxygen being present.
And then the hydrogen comes in and you get this lactate.
But this process of lactate acting as a buffer of fuel
and a positive hormonal signal for other tissues
occurs only if there’s oxygen.
So if you feel the burn,
you definitely want to focus on your breathing
at that point.
That would be the time to take deep inhales
and try and bring more oxygen into your system.
It’s definitely not a time to hold your breath.
And if ever you’ve run to the point of feeling the burn
and then you were exercised in any way on the treadmill
or on the bike or whatever, and felt that burn,
and then you held your breath, it feels much more intense.
By breathing, you bring lactate to the site
and you are able to allow lactate to act more as a buffer,
a fuel, and a hormonal signal.
And the reason I brought this up today is because,
as I mentioned, so many people are interested
in using exercise, not just for sake of improving
physical health and wellbeing and performance,
but also for enhancing their brain.
And there are a lot of data out there
speaking to the findings that exercise of various kinds
can increase neurogenesis, the creation of new neurons.
Well, the unfortunate news is that
while that’s true in mice,
there is very little evidence for enhanced neurogenesis
from exercise or otherwise in humans.
There’s a little bit,
and there are a few sites within the brain
such as the dentate gyrus of the hippocampus,
which may be involved in the formation of new memories.
To be clear, the dentate gyrus is definitely involved
in the formation of new memories,
whether or not the new neurons that are added there
in humans are involved in new memories.
The evidence for that is weak at best, frankly,
whereas in animals, the data are quite strong.
But most of the data point to the fact
that hormonal signals,
things that are transported in the blood
during exercise are what are beneficial for the brain,
excuse me, and that those signals
are not causing the increase in the number of neurons
in the dentate gyrus or otherwise,
that it’s more about the health of the connections
between the neurons, growth factors of various kinds,
things like IGF-1, there’s a long list of these things.
So if you’ve heard that exercise increases
the number of neurons in your brain,
well, that’s not true.
And that probably is a good thing, frankly,
because we always hear more neurons, more neurons,
as if it’s a good thing.
But the brain doesn’t do so well
with bringing in entirely new elements.
It has a hard time negotiating that
and making use of those new elements.
We know about this from things like the cochlear implant
where deaf people are given a device
where they suddenly can hear.
Some people really like that,
deaf people really like that and can benefit from it.
Other deaf people find that it’s very intrusive,
that it’s hard to take an existing neural circuit
in the brain and incorporate a lot
of new information into it.
So new neurons, as great as that sounds,
more neurons, more neurons,
it actually might not be the best way
for the nervous system to change and modify itself
and to promote its own longevity.
So when I tell you,
you know, not such great evidence
for new neurons past puberty,
that’s what the data really show in humans.
And I sort of knock back the data
on exercise and neurogenesis.
Don’t let that depress you.
If you have dementia in your family,
don’t translate that into a necessarily
that you will develop dementia.
Understand that exercise is still beneficial
for the brain and other aspects of the nervous system,
but that it’s going to be doing it
through these hormonal signals,
things like IGF-1,
things like this lactate pathway
when you experience the burn from exercise.
And again, you don’t want to try
and get this feeling of a burn
throughout the entire episode of exercise.
That’ll be far too intense
and would inhibit your recovery.
I don’t think it’d be good for performance either.
It’s only about 10% of your total effort
in any one exercise bout
that’s going to give you this positive effect.
So now you know how to devote a small portion
of your exercise, 10%,
in order for muscle and lactate to benefit other tissues,
namely your heart, your liver, and your brain.
I’d now like to shift our attention
to how to use specific aspects of muscular contraction
to improve muscle hypertrophy, muscle growth,
as well as improving muscle strength.
There are a lot of reasons to want to get stronger.
And I should just mention that it’s not always the case
that getting stronger involves muscles getting bigger.
There are ways for muscles to get stronger
without getting bigger.
However, increasing the size of a muscle
almost inevitably increases the strength of that muscle,
at least to some degree.
Reasons why most everyone should want
to get their muscles stronger
is that muscles are generally getting progressively weaker
across the lifespan.
So when I say getting stronger,
it’s not necessarily about being able to move
increasing amounts of weight in the gym,
although if that’s your goal,
what I’m about to discuss will be relevant to that,
but rather to offset some of the normal decline
in strength and posture and the ability
to generate a large range of movement safely
that occurs as we age.
As I mentioned at the beginning of the episode,
we just tend to lose function in this neuromuscular system
as we get older and doing things to offset that
has been shown again and again to be beneficial
for the neuromuscular system, for protection of injury,
for enhancing the strength of bones and bone density.
So there are a lot of reasons to use resistance exercise
that extend far beyond just the desire
to increase muscle size,
because I know many of you are interested
in increasing muscle size, but many of you are not.
So there’s an important principle of muscle physiology
called the Henneman Size Principle.
And the Henneman Size Principle essentially says
that we recruit what are called motor units.
Motor units are just the connections
between nerve and muscle
in a pattern that staircases
from low threshold to high threshold.
What this means is when you pick up something that is light,
you’re going to use the minimum amount
of nerve to muscle energy in order to move that thing.
Likewise, when you pick up an object that’s heavy,
you’re going to use the minimum amount
of nerve to muscle connectivity and energy
in order to move that object.
So it’s basically a conservation of energy principle.
Now, if you continue to exert effort of movement,
what will happen is you will tend to recruit
more and more motor units with time.
And that process of recruiting more neurons,
more lower motor neurons,
as if you recall from the beginning of the episode,
these lower motor neurons are in our spinal cord
and they actually dump a chemical, acetylcholine on muscle,
cause the muscles to contract.
As you recruit more and more of these motor units,
these connections between these lower motor neurons
and muscle, that’s when you start to get changes
in the muscle.
That’s when you open the gate for the potential
for the muscles to get stronger and to get larger,
if that’s what your goal is.
And so the way this process works
has been badly misunderstood
in the kind of online literature of weight training
and bodybuilding, and even in sports physiology.
The Henneman size principle is kind of a foundational
principle within muscle physiology,
but many people have come to interpret it by saying
that the way to recruit high threshold motor units,
the ones that are hard to get to,
is to just use heavy weights.
And that’s actually not the case.
As we’ll talk about, the research supports
that weights in a very large range
of sort of a percentage of your maximum,
anywhere from 30 to 80%.
So weights that are not very light,
but are moderately light, too heavy,
can cause changes in the connections
between nerve and muscle that lead to muscle strength
and muscle hypertrophy.
Put differently, heavy weights can help build muscle
and strength, but they are not required.
What one has to do is adhere
to a certain number of parameters,
just a couple of key variables
that I’ll spell out for you.
And if you do that,
you can greatly increase muscle hypertrophy, muscle size,
and or muscle strength, if that’s what you want to do.
And you don’t necessarily have to use heavy weights
in order to do that.
Now, I’m sure the power lifters
and the people that like to move heavy weights around
will say, no, if you want to get strong,
you absolutely have to lift heavy weights.
And that might be true if you want to get very strong,
but for most people who are interested
in supporting their muscular
such that they offset any age-related decline in strength
or in increasing hypertrophy and strength to some degree,
there really isn’t a need to lie
about the Henneman size principle,
which many people out there are doing,
and claiming that you absolutely need to use
the heaviest weights possible
in order to build strength and muscle.
So I’m going to explain how all of this works
in simple terms.
So first of all, let’s just talk about what hypertrophy is
and what strength changes in the muscle are.
We can make this very simple as well.
If this were a muscle physiology class,
we would talk all about myofibrils and sarcomeres
and all that stuff.
We’re not going to do that.
That’s not the purpose of today’s conversation.
If you’re interested in that,
as well as a lot of the other information
that I’m going to discuss in more detail,
I highly encourage you to check out the YouTube channel
and the writings of Dr. Andy Galpin.
He’s a PhD and a full professor in exercise physiology.
He’s extremely knowledgeable
in this entire area of science-based tools for hypertrophy,
how strength and hypertrophy really work.
His lab does everything from biopsy on muscles,
working with athletes and typical folks as well.
A lot of the information
that you’re going to hear from me
in the next 15 minutes or so
comes from an extensive exploration of the work
that he and his colleagues have done,
as well as folks like Brad Schoenfield,
another academic who’s superb
in this whole space of muscle physiology,
and from a lengthy conversation that I had
with Andy, Dr. Galpin, prior to this episode.
So if we want to think about muscle hypertrophy,
we have to ask what is changing
when muscles get larger or stronger?
And there are really just three ways
that muscles can be stimulated to change.
So let’s review those three ways
and talk about what happens inside the muscle.
So there are three major stimuli
for changing the way that muscle works
and making muscles stronger, larger, or better in some way.
And those are stress, tension, and damage.
Those three things don’t necessarily all have to be present,
but stress of some kind has to exist.
Something has to be different
in the way that the nerve communicates with the muscle
and the way that the muscle contracts or performs
that makes the muscle need to change.
So this is very reminiscent of neuroplasticity in the brain.
Something needs to happen.
Certain chemicals need to be present.
Certain processes need to happen,
or else a tissue simply won’t change itself.
But if those processes and events do happen,
then the tissue has essentially no option
except but to change.
So muscles move, as I mentioned,
because nerves dump chemical onto the muscles,
but they move because they have these things
called myosin and actin filaments.
And if you want to read up on this,
you can look on the internet.
You can put the sliding filament theory
of muscle contraction
if you really want to go deep down that rabbit hole.
You can learn about this in a muscle physiology class.
But basically, along the length of the muscle,
you have what’s called myosin.
And just think of myosin as kind of like a wire.
It’s like a bunch of beads and wires
that extend across the muscle.
I think that’s the simplest way to describe it.
And the myosin is surrounded
by these little beads called actin.
The way muscles get bigger
is that basically the myosin gets thicker.
It’s a protein, right?
And it gets thicker.
So put this in your mind.
If you’re listening to this,
or even if you’re watching it on YouTube,
the way to think about this whole actin, myosin thing
and muscles getting bigger
is imagine that you’re holding a bouquet of balloons,
a bunch of balloons by their strings,
except you’re not holding the strings all at their bottom.
So the bouquet isn’t nicely arranged.
It’s not like some balloons that are all up at the top
and you’re holding the strings down at the bottom.
Imagine that one of the balloons
is very close to your hand.
Another one is a little bit higher up.
And so this bouquet is very disorganized.
In other words, the string extending out of your hand,
the strings rather extending out of your hand
are all different lengths.
And so the balloons are all over the place.
That’s essentially what myosin looks like in the muscle.
And those strings are what we call the filaments.
And then the myosin head that is the balloon.
When you stress a muscle properly,
or you give it sufficient tension,
or you damage the muscle just enough,
there’s an adaptive response that takes place
where protein is synthesized.
And it’s a very specific protein, it’s myosin.
The myosin gets thicker.
In other words, the balloons get bigger.
So the way to think about muscle growth
and the way to think about muscles getting stronger
is that those balloons get bigger
and the muscle gets thicker.
Now, the question then should be, as always,
how does that happen?
I mean, the muscle doesn’t really know anything
about what’s happening in the outside world.
The way it happens is the nerve,
the neuron has to tell the muscle to get stronger.
And it does that through what we call a signaling cascade.
It talks to the muscle in terms of chemicals.
It doesn’t whisper to it or shout at it,
hey, get bigger.
What it does, it releases certain chemicals
that within the muscle,
there are certain chemicals released rather
that make those balloons, as I’m referring to them,
the myosin get thicker.
So let’s talk about the stimulus for doing that.
And if already in your mind, you’re imagining,
oh my goodness, these balloons of muscle
are going to get thick, thick, thick, thick,
and it’s just going to spiral out of control.
Don’t worry about that.
People invest a ton of time and energy
into trying to make their muscles larger.
It’s actually much harder for people to do
than you might think.
But I do want to give one exception
because it illustrates an important principle
of where we’re headed next.
Everybody has imbalances in how muscles can grow,
how well muscles can grow or how poorly
or how challenging it is for their muscles to grow.
Now, many people who are afraid of like getting too bulky,
for instance, are afraid of lifting weights.
But I think the research shows now that everyone
of pretty much every age should be doing some sort
of resistance exercise,
even if that’s body weight exercises
in order to offset this age-related decline
in muscle contractile ability, muscle strength, et cetera,
improve bone density.
There’s nothing good about getting frail
and weak over time.
And people who invest the effort
into doing resistance exercise of some kind,
whether or not it’s with bands or with weights
or with body weight really benefit tremendously
at a whole body level, at a systemic level,
as well as in terms of muscle strength.
There is a good predictor of how well
or how efficient you will be in building the strength
and or if you like the size of a given muscle.
And it has everything to do with those upper motor neurons
that are involved in deliberate control of muscle.
You can actually do this test right now.
You can just kind of march across your body mentally
and see whether or not you can independently contract
any or all of your muscles.
So for instance, if you are sitting in a chair
or you’re standing, see whether or not
you can contract your calf muscle
just using those upper motor neurons,
sending a signal down
and deliberately isolating the calf muscle, okay?
If you can contract the calf muscle hard
to the point where that muscle
almost feels like it’s trying to cramp,
like it hurts just a little bit,
you know, it’s not going to be extremely painful
nor is it going to have no sensation whatsoever,
chances are you have very good upper motor neuron
to calf control.
And chances are, if you can isolate that,
what they call the brain or mind muscle connection,
and you can contract the muscle to the point
where it cramps a little bit,
that you hold a decent to high potential
to change the strength and the size of that muscle
if you train it properly.
Now, if you have a hard time doing that,
chances are you won’t be able to do that.
If for instance, you focus on your back muscle,
like we all have these muscles called the lat,
the latissimus dorsi muscles,
which basically are involved in chin-ups
and things like that, but their function
from a more of a kinesiology standpoint
is to move the elbow back behind the body, okay?
So it’s not about flexing your bicep,
it’s about moving your elbow back behind your body.
If you can do that mentally,
or you can do that physical movement
of moving your elbow back behind your body
and you can contract that muscle hard,
chances are that you have the capacity
to enhance the strength and or size of that particular muscle
because you have the neural control of that muscle.
This is a key feature of the neuromuscular system
to appreciate as we begin to talk more
about specific protocols.
Because everything about muscle hypertrophy,
about stimulating muscle growth
is about generating isolated contractions,
about challenging specific muscles in a very unnatural way.
Whereas with strength,
it’s about using musculature as a system,
moving weights, moving resistance, moving the body.
The specific goal of hypertrophy
is to isolate specific nerve to muscle pathways
so that you stimulate the chemical
and signaling transduction events in muscles
so that those muscles respond by getting larger.
So there’s a critical distinction
in terms of getting stronger
versus trying to get muscles to be larger,
hypertrophy per se,
and it has to do with how much you isolate those muscles.
Muscle isolation is not a natural phenomenon.
It’s not something that we normally do.
When we walk, we don’t think,
okay, right calf contract, left calf contract.
No, you just generate those rhythmic movements
and of course, there’s no reason for them
to get stronger or larger in response to those movements.
Let’s say you were to do a kind of strange experiment
of attaching 30 pound weights to your ankles
and you were to do those movements.
Well, if you weren’t specifically contracting your calves
in each step, there’s no reason for the calves
to take on the bulk of the work
and you would distribute that work across your hip flexors
and other aspects of your musculature.
Your whole nervous system seeks to gain efficiency.
It seeks to spread out the effort.
So you can nest this as a principle for yourself,
which is if you want to get stronger,
it’s really about moving progressively greater loads
or increasing the amount of weight that you move.
Whereas if you’re specifically interested
in generating hypertrophy,
it’s all about trying to generate those really hard,
almost painful, localized contractions of muscle.
Now, of course, how much weight you use
in order to generate those contractions
will also impact hypertrophy.
But I think most people don’t really understand
the mind-muscle connection.
It sounds like a great thing,
but it’s actually one of the things you want to avoid
if your goal is simply to become more supple
or to become stronger.
You want to do the movements properly and safely, of course,
but it’s the opposite of hypertrophy,
where with hypertrophy,
you’re really trying to make that particular muscle,
sometimes two muscles, do the majority, if not all the work.
Whereas in moving force loads,
in trying to generate activity of any kind,
like lifting a bar or doing a chin-up or something,
those so-called compound movements
that involve a lot of muscle groups,
if your goal is to be better at those,
you want to avoid isolating any one particular muscle.
Now, I know this probably comes across
as a kind of an obvious duh,
especially to the folks that have spent a lot of time
in the gym aimed at getting hypertrophy,
but I think most people don’t appreciate
that it’s the nerve-to-muscle connections
and the distinction between
isolating nerve-to-muscle connections
versus distributing the work of nerve-to-muscle connections
that’s vital in determining whether or not
you generate hypertrophy,
isolated nerve-to-muscle contractions,
versus strength and offsetting strength loss,
which would be distributed nerve-to-muscle connections.
If ever there was an area of practical science
that was very confused, very controversial,
and almost combative at times,
it would be this issue of how best to train.
I suppose the only thing that’s even more barbed wire
of a conversation than that is how best to eat for health.
Those seem to be the two most common areas of online battle.
And the scientific literature has a lot to say
about both of those things.
Again, my sources for what I’m about to tell you
are Professor Andy Galpin and colleagues.
I know there are other excellent people
out there in the field, but I really trust his work.
He does very controlled studies.
He spent a lot of time in this space.
And what’s really exciting
is that in just the last three years or so,
there’s been a tremendous amount of information
to come out about the practical steps that one can take
in order to maximize the benefits
of resistance exercise of any kind.
So I’m going to talk about those,
and I’m going to talk about the research.
I will provide some links,
both to a couple of the more in-depth tutorials
from Dr. Galpin, as well as some of the papers
that the information I’m about to tell you stems from.
There’s a lot of information saying
that you need to move weights
that are 80 to 90% of your one rep maximum,
or 70%, or cycle that for three weeks on,
and then go to more moderate weights.
There are a lot of paths.
As some people say, there are a lot of ways
to add up numbers to get 100.
There’s a near infinite number of ways
to add up different numbers to get to 100.
And what’s very clear now
from all the literature that’s transpired,
and especially from the literature
in this last three years,
is that once you know roughly your one repetition maximum,
the maximum amount of weight
that you can perform an exercise with
for one repetition in good form, full range of motion,
that it’s very clear that moving weights,
or using bands, or using body weight, for instance,
in the 30 to 80% of one rep maximum,
that is going to be the most beneficial range
in terms of muscle hypertrophy and strength,
so muscle growth and strength.
And there will be a bias.
If you’re moving weights that are in the 75%, 80% range,
or maybe even going above that, 85 and 90%,
you’re going to bias your improvements
towards strength gains.
This is true.
And if you use weights that are in the 30%
of your one repetition maximum, or 40% or 50%,
and doing many more repetitions, of course,
then you are biasing towards hypertrophy
and what some people like to call muscle endurance,
but that’s a little bit of a complicated term
because endurance we almost always think of
as relating to running or swimming
or some long bouts of activity.
So 30 to 80% of one repetition maximums,
it doesn’t really seem to matter for sake of hypertrophy,
except at the far ends
when you’re really trying to bias for strength.
Now, it is clear, however,
that one needs to perform those sets to failure
where you can’t perform another repetition
in good form again, or near to failure.
And there’s all sorts of interesting nomenclature
that’s popping up all over the internet,
some of which is scientific,
some of which is not scientific
about how you are supposed to perceive
how close you were to failure, et cetera.
But there are some very interesting principles
that relate to how the nerves connect to the muscles
that strongly predict whether or not this exercise
that you’re performing will be beneficial for you or not.
So here’s how it goes.
For individuals that are untrained,
meaning they have been doing resistance exercise
for anywhere from zero, probably out to about two years,
although for some people it might be zero to one year,
but those are the so-called beginners,
they’re sort of untrained.
For those people, the key parameter
seems to be to perform enough sets
of a given exercise per muscle per week, okay?
The same is also true for people that have been training
for one or two years or more.
What differs is how many sets to perform
depending on whether or not you’re trained or untrained.
So let’s say you’re somebody
who’s been doing some resistance exercise
kind of on and off over the years,
and you decide you want to get serious about that
for sake of sport or offsetting age-related declines
in strength, the range of sets to do
in order to improve strength,
to activate these cascades in the muscle,
ranges anywhere from two, believe it or not,
to 20 per week.
Again, these are sets per week,
and they don’t necessarily all have to be performed
in the same weight training session.
I will talk about numbers of sessions.
So it appears that five sets per week
in this 30% to 80% of the one repetition maximum range,
getting close to failure
or occasionally actually going to full muscular failure,
which isn’t really full muscular failure,
but the inability to generate a contraction of the muscle
or move the weight in good form.
I’ll go deeper into that in a moment,
but about five sets per week is what’s required
just to maintain your muscle.
So think about that.
If you’re somebody who’s kind of averse
to resistance training,
you are going to lose muscle size and strength.
Your metabolism will drop.
Your posture will get worse.
Everything in the context of nerve to muscle connectivity
will get worse over time
unless you are generating five sets
or more of this 30% to 80%
of your one repetition maximum per week, okay?
So what this means is for the typical person
who hasn’t done a lot of weight training,
you need to do at least five sets per muscle group.
Now that’s just to maintain.
And then there’s this huge range
that goes all the way up to 15,
and in some case, 20 sets per week.
Now, how many sets you perform
is going to depend on the intensity
of the work that you perform.
This is where it gets a little bit controversial,
but I think nowadays most people agree,
and Dr. Galpin confirmed that 10%,
not to be confused with the 10% we discussed earlier,
but 10% of the sets of a given workout
or 10% of workouts overall
should be of the high-intensity sort
where one is actually working to muscular failure.
Now, I say not true muscular failure
because in theory, you have a concentric movement,
which is the kind of lifting of the weight,
and then you have the eccentric portion
of muscle contraction, which is the lowering.
And the eccentric movements,
because of the way that muscle fibers lengthen
and that sliding actin myosin that we talked about before,
you’re always stronger in lowering something
than you are in lifting it.
But the point being that most of your training,
most of your sets should be not to failure.
And the reason for that is it allows you
to do more volume of work
without fatiguing the nervous system
and depleting the nerve to muscle connection
in ways that are detrimental.
So we can make this simple.
Perform anywhere from five to 15 sets
of resistance exercise per week,
and that’s per muscle,
and that’s in this 30 to 80%
of your one repetition maximum.
That seems to be the most scientifically supported way
of offsetting any decline in muscle strength
if you’re working in the kind of five set range
and in increasing muscle strength
when you start to get up into the 10 and 15 set range.
Now, the caveat to that is everyone varies
and muscles vary in terms of their recoverability.
Depending on how well you can control
the contraction of muscles deliberately,
and you can actually figure that out
by sort of marching.
You might take five minutes
and just kind of march across your body
and mentally try and control the contractions of muscles
in a very deliberate way
to the point where you can generate a hard contraction.
And you may have to move a limb
in order to do this, by the way.
I’m not talking about just mentally contracting your bicep
without moving your wrist.
I’m talking about doing that without any weight in hand
or any band or any resistance.
If you can generate a high intensity contraction
using these upper motor neuron
lower motor neuron pathways to muscle,
you might think, well,
I should perform many more sets, right?
But actually the opposite is true.
If you can generate high intensity muscular contractions
using your brain, using your neurons,
it will take fewer sets in order to stimulate the muscle
to maintain itself and to stimulate the muscle
in order to grow or get stronger.
So the more efficient you are in recruiting motor units,
remember Henneman size principle,
the recruitment of more motor units,
which isn’t just muscles, it’s nerve to muscle connections.
The better you are at doing that,
the more you will recruit
these so-called high threshold motor units,
the ones that are hard to get to,
the more you’ll kick off the cascades of things
within muscle that stimulate muscle growth and strength.
So if you have muscles that are challenging to contract,
it’s going to take more sets
in order to stimulate the desired effect in those muscles,
not fewer, okay?
If you have muscles that you are very good
at generating force within, it’s going to take fewer sets.
Now, how many sets?
You are going to have to determine that.
It’s going to depend for those of you
that are using like 50% of your one repetition maximum,
because you’re doing a lot of repetitions,
you might find that three or four,
five sets will maintain the muscle.
You might decide to do that once at one point in the week
and then do it again, right?
So if you’re going for 10 sets a week,
you can divide that among two sessions
or you can do that all in one session.
The data really show it doesn’t matter.
There are some differences in terms of whether or not
you’re trying to generate maximum intensity
within a workout or whether or not
you want to spread that out.
But in general, resistance workouts of any kind
tend to be best favored by workouts
that are somewhere between 45 minutes and 60 minutes.
And generally not longer than 60 minutes
because that’s when all the things like cortisol
and some of the inflammatory pathways
really start to create a situation in the muscle
and in the body that’s not so great for you.
So it’s not a hard and fast rule,
you know, that the ax doesn’t drop at 60 minutes,
but it’s pretty clear that performing this
five to 15 sets per week,
whether or not it’s in one workout
or whether that’s divided up across multiple workouts
is really what’s going to be most beneficial.
And please do keep in mind Henneman’s size principle
and the recruitment of motor units.
And remember, the better you are
at contracting particular muscles
and in isolating those muscles,
the fewer sets likely you need to do
in order to get the desired effect.
Now, what about people who have been training for a while?
If you’re somebody who’s been doing
weight training for a while,
the data point to the fact that
more volume can be beneficial,
even for muscles that you are very efficient at contracting.
Now, the curve on this, the graph on this
begins again at about five sets per week
for maintaining a given muscle group
and extends all the way out to 25 or 30 sets per week.
However, there are individuals who for whatever reason
can generate so much force,
they’re so good at training muscles
that they can generate so much force
in just four or six or eight sets
that doing this large volume of work
is actually going to be counterproductive.
So everyone needs to figure out for themselves,
first of all, how often you’re willing to do
resistance exercise of any kind.
And again, it doesn’t matter if you’re using bands
or weights or body weight.
For instance, if you’re doing chin-ups,
chances are, unless you are very strong,
that you’re not using weights,
you’re just using something that you can hold onto.
Or if you’re doing push-ups,
some of you will be working in that 30 to 80%
of your one repetition maximum range.
It doesn’t necessarily mean that you have to be
moving weights in a gym, for instance.
So the purpose here is to figure out
what muscles you’re trying to train.
That’s an issue that we’ll talk about in a moment.
And then it does appear that somewhere between
five and 15 sets per week is going to be
the thing that’s going to work for most people.
Now, this is based on a tremendous amount of work
that was done by Andy Galpin and colleagues,
Brad Schoenfield and colleagues and others,
There’s a huge group of people out there
doing exercise physiology and a small subset of them
that are linking them back to real world protocols
that don’t just pertain to athletes.
So that’s mainly what I’m focusing on today.
And surely there will be exceptions.
Now, if you are going to divide the sets across the week,
you’re not going to do all 10 sets, for instance,
for a given muscle group in one session.
Then of course, it’s imperative that the muscles
recover in between sessions.
And we are going to talk about recovery
both at the systemic level, the whole nervous system,
and at the local level, the nerve to muscle
and local even muscle level.
We’ll talk about that in about 10 minutes
when we talk about recovery.
I do want to mention something very important,
which is that everything I’m referring to here,
it has to do with full range of motion, okay?
And you might ask, well,
what about the speeds of movements?
This is actually turns out to be
a really interesting data set.
For generating explosiveness and speed,
so for sprinters or throwing sports,
or for people that want to generate a lot of jumping power,
it does appear that learning to move weights
as fast as you safely can,
especially under moderate to heavy loads,
can increase explosiveness and speed.
And most of that effect is from changes in the neurons.
It’s not from changes in the muscle,
it’s from changes in the way that the upper motor neurons
communicate with the lower motor neurons
and generating a pathway, a neural circuit, as we call it,
that is very efficient at generating action potentials,
which are the electricity within neurons
to trigger the muscle.
Now, of course, there are events that happen
from nerve to muscle,
but the takeaway from that enormous literature, frankly,
is that if you want to get faster,
yes, it can be beneficial to get stronger,
but if you want to dedicate resistance training
specifically to jumping higher, to running faster,
to throwing further, and these sorts of things,
that learning to generate force with increasing speed
is going to be beneficial.
On the flip side of that,
for people that want to get stronger,
it appears that the slowing down of the weight
as things get harder is a key parameter
in recruiting those high threshold motor units.
So let me phrase that a little bit differently.
Think about a set in the gym,
or think about a set of pushups or a set of pull-ups.
Initially, you can move very fast if you like.
If you want to generate hypertrophy,
the goal really is not necessarily to move super slow,
but to isolate the muscle and therefore not to use momentum
rather than lift weights, as they say, challenge muscles.
If you want to get stronger,
you’re going to be distributing that effort
over more muscles and more of your nervous system.
For generating explosiveness and speed,
it’s very clear that learning to generate forces quickly
and to move heavy or moderately heavy loads quickly
is going to be beneficial
because of the way that you train the motor neurons.
And of course, changes in the muscle.
But this could look different for different sports.
And obviously you want to make safety paramount.
If you’re injured,
you’re not going to be able to train at all for sport
or for any purpose that is.
And so what this would involve is something like 60 to 75%
of a one repetition maximum.
And then in a controlled way,
moving that as quickly as one can throughout the entire set
and certainly not going to failure
because as you approach failure,
the inability to move the weight with good form,
the weight inevitably slows down.
In fact, there are a lot of new technologies now
that are focused on informing people
of how quickly the bar or weight is moving.
I saw an advertisement for this the other day.
There are things that people can attach to bars
that will literally speak to you as you’re doing a set
and inform you whether or not you’re moving
four times more slowly per rep
than you were at the beginning
and trying to hone in on the exact speed of movement.
In talking to these experts prior to this episode,
it does appear that for sake of hypertrophy,
as long as you’re not moving the muscles so quickly
that you start to distribute the effort
to lots of other muscles, it doesn’t really matter.
Because as the set gets harder,
the motor units that you recruit will increase
the number of neurons that you recruit
and the number of muscle fibers
in between these high threshold muscle fibers will increase.
And so it’s really only for purposes of hypertrophy
that you really need to be concerned
about how quickly the weight is slowing down.
However, if you’re trying to get faster, more explosive
and generate more speed and jumping power,
throwing power, things of that sort,
you never really want to use a weight
or get to a portion of the set
where you’re moving the bar very, very slowly.
And I’m sure as I say that,
some of the exercise physiologists
and advanced trainers out there
will come after me with pitchforks, which is fine.
I’d love to see the literature that shows
that low gear, slow movements with very heavy weights
can indeed improve explosiveness.
And that may in fact be the case,
but the data that I was able to access was essentially
as I described just a moment ago.
So as you’re probably starting to realize,
you need to customize a resistance practice
for your particular needs and goals.
And I certainly am not the first to suggest
that people periodize their training,
that they do things from anywhere from one month
to six months and to see how it goes
and to make modifications as they go.
Because the nervous system,
in particular the neuromuscular system
changes very quickly at the beginning of training.
In fact, some of the changes that one can see
when they first embrace or start resistance training
can be very remarkable, but they tend to slow over time.
So we’ve talked about a few principles.
The fact that you need to get sufficient volume,
you need at least five sets to maintain
and you probably need about 10 sets per muscle group
in order to improve muscle.
That moving weights of moderate
to moderately heavy weight quickly
is going to be best for explosiveness.
That isolating muscles
and really contracting muscles hard,
something that you can test
by just when you’re outside the training session,
seeing whether or not you can cramp the muscle hard
will tell you your capacity to improve hypertrophy
or to engage strength changes in that muscle.
That your ability to contract a muscle hard
is inversely related to the number of sets
that you should do in order to isolate
and stimulate that muscle.
And there are some other things
that can enhance the whole process
of building nerve to muscle connections,
making them more efficient
and generating if you like more strength and hypertrophy.
One of them I loathe to say,
I was told is in between set contractions.
The other name for this is the people in the gym
does typically seem to be guys in the gym
flexing their muscles in between sets.
And indeed the research supports the fact
that contractions of about 30 seconds
in between the actual work sets,
they’re not going to favor better performance
on the work sets.
If anything, they’re going to compromise them,
but those hard contractions in between sets
for a variety of reasons related to local muscle metabolism,
as well as what we talked about before,
which are stress, tension and damage,
they seem to improve stress, tension and damage
and the nerve to muscle contraction
in ways that facilitate hypertrophy.
In other words,
you see that person flexing in between sets in the gym,
provided that they’re really isolating that muscle
and provided it’s one that they ought to be improving.
Not one of these people
that always skips leg day type of people.
These people are highly asymmetric,
although that’s up to them.
That process of flexing in between sets
does seem to improve the nerve to muscle connection
and enhance hypertrophy.
And I say, I was loath to say it
because nowadays with phones,
it seems like the end of every set includes a selfie.
That’s sort of like the 11th rep of every set.
I like to joke.
It seems like very few people are capable
of actually going into the gym
and doing a workout without taking a picture of themselves,
which I think is fine if that’s your thing.
Although I must say that the athletes that I know
and even the recreational athletes that I know
who seem to get the most out of their training
and who also seem to get the most
out of other aspects of their life
seem to be able to control their phone behavior,
both in the gym and outside of the gym.
But that’s more of an editorial point there.
In an earlier episode,
I talked about estrogen and testosterone.
And during that discussion,
I talked about the use of resistance exercise
specifically for increasing testosterone,
both in men and in women.
And indeed that is a powerful effect of resistance exercise.
And indeed it’s mediated by the nerve to muscle connections.
We talked about that in that earlier episode.
I just want to briefly mention that protocol
since it’s distinctly different
from the other protocols I’ve talked about today.
The protocols I’ve talked about today thus far
of explosive movements or of hypertrophy based training,
provided the training is 60 minutes or less
will cause increases in serum testosterone
that’s been shown over and over again.
And if the session extends too long past 75 minutes
and is of sufficiently high intensity,
chances are testosterone levels will start to drop
and cortisol levels will go up
in ways that can be detrimental to recovery
and the goals of the training.
But that’s different than training
that’s specifically geared toward increasing testosterone.
Duncan French, who’s one of the directors
of the UFC Performance Center,
when he was a graduate student
at University of Connecticut stores,
did some beautiful work.
He and his colleagues found the ideal training protocols
for stimulating testosterone release,
which is something that many people want to do
for a variety of reasons.
And that involved doing six sets of 10 repetitions,
even if it requires lightening the weight
on one set to the next,
with about two minutes, 120 seconds rest in between sets,
which if you think about it is pretty short rest
and is pretty darn hard work.
Now, what’s interesting is that
there’s a very limited threshold
for increasing testosterone.
That protocol of six sets of 10 repetitions
led to these big increases in serum testosterone.
But if people did 10 sets of 10,
so just four more repetitions per set,
then testosterone did not increase.
In fact, you got more of this catabolic cortisol
You get other benefits from the so-called
10 sets of 10 protocol,
but not the testosterone increase
and maybe even reductions in testosterone.
Now it’s important to point out that
that six sets of 10 was done with big compound movements.
So things like squats or deadlifts or chin-ups
or things of that sort.
And those were done as single sessions,
not in concert with a bunch of other exercise.
Although if athletes are doing that,
there’s no reason why they couldn’t also do
other types of training elsewhere in the week.
I asked Duncan about this and he mentioned that
that done twice a week is probably the maximum amount
that anyone could do that
and still maintain this increase in testosterone.
It’s a very interesting protocol
because as a neuroscientist,
it’s amazing to me that six sets of 10 repetitions
with something causes a distinctly, excuse me,
causes a distinctly different result
in terms of hormone output
than 10 sets of 10 of the exact same movement.
And it speaks to the exquisite way
in which nerve to muscle connections
dictate the whole physiology of your entire system.
If there’s a theme that I really want to bring forward today
is that weight training or resistance training of any kind
is really used for either systemic effects, right?
10% of training done where you’re feeling that burn,
which means lactate will be present
and sending signals to your brain
and your heart and to your liver that are beneficial
or isolating muscles,
which may also generate a kind of a lactate
which is associated with the burn result.
But that isolation of muscles is distinctly different.
So systemic versus isolated.
Those are the two general ways
in which resistance training can be applied.
So I just wanted to mention that earlier protocol
because it’s well-supported by the literature.
If you were to incorporate that protocol,
you might ask,
well, then can you do any other weight training
during the week?
And sure, of course you can provided you’re recovering.
So let’s talk about how you know if you’re recovering,
how you know if a muscle is recovered
and how you know if your whole system is recovered
because recovery is what dictates
whether or not you can come back
and do more work of a different kind,
meaning you do a leg training one day,
can you and should you come back
and do upper body training the next day?
And it dictates whether or not you’ll see any improvement
from session to session at all.
Before I talk about recovery,
I just want to make sure I nail down the details
that I was able to extract from the literature
and from my conversation with Dr. Galpin.
If you’re wondering how quickly to perform repetitions
for sake of hypertrophy or strength gains,
anywhere from a half a second per repetition
all the way up to eight seconds per repetition,
it doesn’t seem to matter.
Again, if you’re thinking about explosiveness
or building speed,
or you’re specifically using resistance training
to build endurance, that’s a separate matter.
We talked about explosiveness and speed.
I’ll talk about endurance in a few moments.
We also talked about in-between set contractions,
so-called selfie effect of people flexing
a particular muscle,
isolating a particular muscle between sets.
Just want to mention that would be a terrible thing to do
if your goal is performance on sets.
So moving a particular amount of weight,
that’s actually going to diminish the amount of weight
that you can move.
It’s going to enhance muscle growth
and it’s going to enhance the nerve to muscle isolation
of that particular pathway.
So again, that flexing between sets
is going to favor hypertrophy, not performance.
If you’re trying to get stronger,
you’re trying to move more weights,
you’re trying to distribute work,
and you’re trying to do maybe skill training
then flexing between sets is absolutely the wrong thing
to do for obvious reasons.
You’re fatiguing the muscle further.
Just remaining still or walking around a little bit
has been shown to be beneficial
in terms of moving some of the lactate out of the muscle,
as well as just recovering between sets.
Now, how long to recover between sets?
This is a question for the testosterone protocol.
Duncan French and colleagues found
that it was about two minutes,
keeping that really on the clock, two minutes, not longer.
For hypertrophy and for strength gains,
it does seem that resting anywhere from two minutes
or even three or four, even five or six minutes
can be beneficial.
And if you’re interested in expanding the volume of work
that you can do in a given session,
at high capacity, at high intensity with a given weight,
please see the episode that I did on cold and performance
about supercharging performance,
which is based on the work of my colleague, Craig Heller,
in the biology department at Stanford,
which talks about palmar cooling,
about how you can cool the core of the body
best through the palms,
using these particular venous portals
that are only present in your hands.
People are now doing this with ice packs or with gel packs.
There are a number of different ways one can do this.
I talk all about that in that episode.
It allows you to do more repetitions
and more work at a given weight over time.
So rather than getting 10 repetitions
and then eight and then seven and then six,
through proper use of palmar cooling,
one can do 10, 10, 10, 10, and even add sets.
And that’s one way that one can accomplish
higher volume work
without having to drop the weight considerably.
So that’s where you can hit that really sweet spot,
if that’s your goal, of getting strong
and generating some hypertrophy.
Because as soon as you have to drop to lighter weights,
then you’re shifting more towards hypertrophy and endurance
and less toward strength in a given muscle.
So check out that episode.
The last thing besides between set contractions
and whether or not you’re distributing work
or whether or not you’re really trying to isolate muscles
is this notion of pre-exhausting muscles.
It’s been shown over and over again that, for instance,
if you want to generate force in a given muscle
and really isolate that,
doing the isolation work before a compound movement.
So this would be, you know, leg extensions,
the thing where you sit
and you extend your toes up toward the ceiling.
Leg extensions before squats will allow the squats
to target that muscle group more effectively.
And that makes perfectly good sense
based on the Henneman size principle
and fatiguing motor units.
It should be obvious why that’s the case.
But of course, that’s going to be anti-performance
in terms of how much weight you can lift
and maybe even the form that you can maintain
when you move to the bigger compound movement.
So you really have to ask yourself a number of questions.
How good are you at isolating a given muscle?
Therefore, how many sets do you want to do?
How often are you willing to train?
Therefore, how many sets are you going to do
in a given session
versus how many are you going to distribute across the week?
Are you aiming for performance?
Are you going to distribute that work
across the nervous system and musculature?
Are you trying to move weights
or are you trying to challenge muscles?
If you’re trying to challenge muscles,
then you really want to focus on things
like this pre-exhausting,
the isolation of a muscle before the compound movement.
Your performance on compound movements
will absolutely suffer,
but your ability to isolate that muscle
and generate hypertrophy through the accumulation
of larger myosin, those bigger balloons, will benefit.
And once again, if you’re trying to get faster,
then the speed of the movement really matters.
So how do we know if we’ve recovered?
How can we test recovery?
And this is not just recovery from resistance training.
This is recovery from running, recovery from swimming.
Up until now, I’ve been talking about resistance training
more or less in a vacuum.
I haven’t even touched on the fact
that many people are running
and they’re doing resistance training,
or they’re swimming and they’re doing resistance training.
It’s not simply the case that if a given muscle is fatigued,
you can just work other muscles
because even if you’ve beautifully isolated a muscle,
let’s say you have incredible abilities
to isolate just your quadriceps, for instance,
and you do a workout where you isolate your quadriceps,
you do your six sets of intense work,
or maybe use Palmer cooling,
and you’re able to do 12 sets of intense work,
and you’re done, and that muscle group,
the next day is certainly not going to be recovered
unless you’re somebody who’s extraordinary at recovery
or you’re enhancing your recovery through chemical means,
which we’ll talk about at the end.
Well, you can assess systemic recovery,
meaning your nervous system
and your nervous system’s ability to generate force
both distributed and isolated through three main tests.
And fortunately, these tests are very simple,
and two of them are essentially zero cost,
require no equipment.
HRV, heart rate variability, has made its way finally
into the forefront of exercise physiology
and even into the popular discussion.
I’ve talked about HRV before,
how when we exhale, our heart rate slows down
because of the way that our diaphragm is connected
to our heart and to our brain
and the way our brain is connected to our heart.
Excuse me, when we inhale, our heart rate speeds up,
and that is the basis of heart rate variability.
Heart rate variability is good.
It means that you’re breathing properly.
And when I say it’s good,
it means you want a lot of heart rate variability.
You don’t want a heart rate
that is high or low consistently over time.
That might come as a bit of a surprise
for you endurance athletes
who probably are trying to accomplish
your endurance work at a steady cadence
and really hit that nice sweet spot
where you’re breathing rhythmically,
your heart rate’s going rhythmically,
you’re in that steady heart rate,
and then away from exercise,
you have a nice low heart rate, as they say.
Well, nice low heart rate isn’t necessarily always so nice.
Turns out that introducing bouts
of increasing your heart rate during exercise,
and even through your waking day,
through stressful events even,
is provided their brief, is beneficial.
A good nerve to heart system
benefits from being able to increase heart rate
and decrease heart rate.
Heart rate variability is good.
So you don’t want high heart rate,
you don’t want low heart rate all the time.
But heart rate variability is difficult
for a lot of people to measure.
There are some devices that will allow you to do that,
various watches and devices.
There are more devices becoming available all the time.
Hopefully soon, some that are integrated with your phone
that involve no contact or anything on your body.
But those do carry some costs,
and they are not perfect yet.
The measures of heart rate variability
that one can use while in movement
are still in the phase, I would say,
of technology development where everyone isn’t using them.
Let’s leave it at that.
There are two measures, however,
whether or not you recovered,
that you can use first thing in the morning
when you wake up, maybe after five, 10 minutes, if you like,
but ideally right when you wake up
in order to assess how well recovered you are,
and therefore whether or not you should train
your whole system at all that day.
The first one is grip strength.
Grip strength, the ability to generate force
at the level of squeezing the fist
or squeezing down on something
might seem like kind of a trivial way to assess recovery,
but it’s not because it relates to your ability
to use your upper motor neurons,
to control your lower motor neurons,
and to generate isolated force.
And so that’s really what you’re assessing when you do that.
Some people will use one of these grip tools,
or Costello has this toy that’s shaped like a donut,
and it’s this hard rubber, and I’ve tried this before.
You know, if I’ve been working really hard,
not sleeping very well, or I’ve been training a lot,
any one or combination of those things, my grip suffers.
I can’t actually squeeze that thing down
as much as I can Costello,
because he was born with a, you know, like a 24-inch neck,
and even though he’s never touched a weight,
somehow he can just clamp down on that thing,
and it just, you know, he can turn it
into a pancake with ease,
and he likes to chuckle while I struggle with this thing.
But on a good day, I can squeeze this thing
so that I eliminate the hole in the donut, so to speak.
You can also take a floor weight, and excuse me,
a floor scale, and squeeze the scale,
and see how much force you can generate.
I would do that as a baseline to establish
what you can do when you’re well-rested.
And then if you do that in the morning,
you can see whether or not you’re able to generate
the same amount of force,
or you could use the rubber donut or something.
A lot of this is very subjective.
With the scale, you’re really trying to assess
whether or not you can generate the same amount of force.
If you start seeing a 10% or 20%,
certainly reduction in that, that’s concerning.
It means that your system,
that your nervous system as a whole,
it’s not necessarily fatigued.
It’s that the pathways from nerve to muscle
are still in the process of rewiring themselves
in order to generate force.
And you might think, well, I trained one muscle group one day.
Why am I having a hard time doing this
for a completely different muscle group?
Doesn’t make any sense.
But there’s something about the upper motor neuron
to lower motor neuron pathway generally
that allows you to use something like grip strength
as a kind of a thermometer, if you will,
of your ability to recover.
So look for your ability to generate force in grip
when you first wake up.
It’s not going to be as good as it is at 3 p.m.
after a cup of coffee and a couple meals,
but the point isn’t performance overall.
The point is to assess whether or not you’re getting better,
worse, or the same from day to day.
The other one that’s really terrific,
and the Andy Galpin’s group is using,
and I’m delighted about this
because it relates to something
that my lab is very excited about as well,
is carbon dioxide tolerance.
So this is a really interesting tool
that endurance athletes, strength athletes,
I think can all benefit from.
In fact, athletes and people of all kinds,
even if you’re not an athlete,
even if you’re not exercising at all,
there’s a good question of whether or not
your system as a whole is doing okay or not.
You know, we rely on the thermometer.
Do we have a fever or not?
We rely on subjective things.
You know, do I feel good or not?
Am I digesting well or not?
Those are all subjective.
The carbon dioxide tolerance test is,
it’s objective in that it measures your capacity
to engage the so-called parasympathetic arm
of your nervous system,
which is the calming aspect of your nervous system,
and it measures your ability to consciously control
a particular skeletal muscle, which is your diaphragm.
So here’s how you do the carbon dioxide tolerance test.
You wake up in the morning.
If you have to use the restroom first, do that,
but try and stay away from your phone.
Try and, if you have your phone, put it on airplane mode,
go to the timer or use a hand watch
or some other way of measuring time.
Stay off social media for just a few seconds.
It’ll be okay.
And what you’re going to do is you’re going to inhale
through your nose as deeply as you can.
You can do this lying down, you know, sitting, whatever.
Inhale through your nose and then exhale all the way.
So that’s one.
You’re going to repeat that four times, okay?
So inhale, exhale, inhale, exhale, inhale, exhale.
Exhale, inhale, exhale, four times.
And ideally you’re inhaling through the nose
and you’re exhaling through the mouth.
That’s just the beginning
of this carbon dioxide tolerance test.
Then you take a fifth inhale as deep as you can
through your nose, fill your lungs as much as you can.
And if you can try and expand your,
make your stomach go out while you do that,
that means that your diaphragm is really engaged.
So you’re inhaling as much as you possibly can.
Then hit the timer.
And your goal is to release that air
as slowly as possible through your mouth.
So it looks like you have a tiny, tiny little straw
in your mouth and you’re letting it go
as slowly as you possibly can.
Measure what we call the carbon dioxide blow-off time
or discard rate.
I know you can all sit with lungs empty
after you eliminate all that air,
but don’t lie to yourself.
Don’t stop the timer when you’ve been sitting
with your lungs empty for a while.
Stop the timer when you are finally no longer able
to exhale any more air.
Okay, so four.
So you do inhale, exhale, inhale, exhale,
inhale, exhale, inhale, exhale slowly.
I just said it quickly for sake of time.
Then you do this fifth big inhale through your mouth
and I’m not going to do it for the full duration.
And then you’re measuring that time.
Your carbon dioxide discard rate will be somewhere
between one second and presumably two minutes.
Two minutes would be a heroic carbon dioxide discard time.
30 seconds would be more typical.
20 seconds would be fast.
If your carbon dioxide discard time is 20
or 25 seconds or less,
you are not necessarily recovered
from your previous day’s activities.
Okay, there’s ways to push through this,
but hold onto that thought for a moment.
If your carbon dioxide discard time is somewhere
between about 30 seconds and 60 seconds,
you are in what we would call kind of the green zone
where you are in a position to do more physical work.
And if your carbon dioxide discard time is somewhere
between 65 and 120 seconds,
well then you have almost certainly
recovered your nervous system.
I’m not talking about the individual muscles,
but your nervous system is prepared to do more work.
And Andy’s lab has great data on this
as it relates to exercise physiology.
I think that story should be out
in the not too distant future.
My lab has been using carbon dioxide discard time
to look at anxiety and recovery from bouts of anxiety.
So two totally independent projects,
but using the same measure.
So you’ve got HRV, which requires some technology usually.
You’ve got grip strength,
which you can assess subjectively
or you can use a floor scale.
And now you have carbon dioxide tolerance.
You want to do this in the morning when you wake up
and keep track, just write down in a little book
or maybe just keep track in your mind
of your carbon dioxide discard time.
If you find that your discard times are dropping,
even if they’re in the 40 second range or 50 second range,
but normally you can do 75 seconds or 120 seconds.
If they’re starting to drop by anywhere from 15 to 20%,
you’re veering in the direction of not recovering.
And I’m really keen on this tool
because everybody has different recovery abilities.
Some people are eating really well
and sleeping really well.
Some people have minimal stress
or can buffer stress really well.
Other people, they dissolve into a puddle of tears
if they read one text message that’s troubling or whatever.
And I realize, and I say that with sympathy,
I realize people have varying levels of stress
and demand in their life.
It’s just impossible to prescribe an entire protocol
that says, okay, yes, you should train today.
And this is exactly what you should do.
No, you shouldn’t.
Use carbon dioxide discard rate
because A, it’s valuable, it’s informative.
B, it’s zero cost.
And C, it’s something that you can track objectively
And that’s really the key.
And I just should, I’d be remiss if I didn’t say
that what carbon dioxide discard rate is tapping into
is your ability to mechanically control your diaphragm.
Certainly that’s one aspect of it,
but that relates in a very direct way
to your ability to put the brake on your stress system,
to engage the so-called parasympathetic
or calming arm of your autonomic nervous system.
And another thing that Andy Galpin’s group is testing
is at the offset of training after your run,
after your weight training session,
maybe even after your plyometrics session,
we didn’t really talk about jumping and throwing
and that sort of thing.
Maybe we’ll talk about it in a future episode,
but they and other groups, including some elite athletes
and other groups that are very interested
in physical performance are using a tool
where they deliberately disengage for five minutes
at the end of training.
They deliberately engage this calming
or parasympathetic arm of the nervous system.
And you can do that through any number of different tools.
I’m a big fan of respiration tools
because they’re always available to you.
Your breathing is always there.
I talk about some of these tools in previous episodes,
but you could use things like non-sleep deep rest,
NSDR at the end of a training session.
You could do 10 physiological size,
double inhales through the nose, followed by long exhales.
That will definitely engage
the parasympathetic nervous system at the end of training.
So rather than finish your training session
and then just hop onto your phone,
serious athletes and people who are serious about recovery
initiate that recovery at the very end of their training.
And they start to kickstart that recovery process rather,
and they measure CO2 tolerance in the morning.
So there are several groups that are doing that.
In fact, I know several groups because I’m working with them
that are using physiological size between sets
in order to recover their nervous system
and maintain nerve to muscle contractibility,
maintain focus throughout their training session,
enhance their focus by doing a few physiological size.
So double inhale, exhale in between sets.
So they’re getting very focused and very intense
about their strength work or explosiveness work
or muscle isolation work during their sets.
And then in between sets,
they’re deliberately disengaging the nervous system
and then they’re re-engaging it again.
So I just wanted to emphasize that.
So recovery is a complex process.
It’s got a lot of things,
but the CO2 tolerance test should be a valuable tool.
Now, another tool for recovery
that people are very excited about
is the use of cold and the ice bath.
And this is important.
If you are somebody who uses cold through cold shower
or ice bath or jumping in a lake or a river,
whatever it is that you use to generate cold
as a recovery tool,
you should be aware that there are data starting to emerge
that if your goal is recovery or strength improvements,
using cold within the four hours following a workout,
I’m not talking about Palmer cooling,
I’m talking about whole body cooling
or cooling from the neck down.
Yes, it will reduce inflammation.
Yes, it will reduce the amount
of delayed onset muscle soreness.
One readout of how intense or damaging a given workout was,
not the only readout.
But it does seem to interfere
with some of the things like mTOR pathways,
the mammalian targeted rapamycin pathway
and other pathways related to inflammation
that promote muscle repair, remember, and muscle growth.
Remember, stress, tension, and damage
are the stimulus for nerve to muscle connections to change
and for muscles to get bigger, stronger, and better.
And so if you’re getting into the ice bath after training
or taking a really cold shower
after doing resistance training,
you are likely short-circuiting the improvements
that you’re trying to create.
Now, athletes who are trying to recover quickly
so that they can get back into more training sessions,
or let’s say you’re somebody who doesn’t really want
to gain much strength or hypertrophy,
and you’re mainly focused on endurance
and you want to do more endurance work
and you’ve been weight training,
well, then exposing yourself to cold can be beneficial,
but you’re not going to get as great of benefits
from the resistance training.
In other words, cold after resistance training
seems to short-circuit some of the benefits
of that resistance training.
There are some other things that can short-circuit
the benefits of resistance training as well.
One of those is antihistamines.
Some interesting data were published recently,
I believe it was in scientific reports, yes,
that showed that antihistamines can prevent
some of the benefits of cardiovascular exercise,
of endurance-type work, so running, swimming,
fairly long duration, or even sprint-type work,
as well as inhibit some of the processes
associated with resistance training.
Remember, resistance training or endurance training,
that’s a stimulus for stress,
and the adaptation to that stress is how you get better,
that you can run further, faster, lift more weight,
hypertrophy the muscle, et cetera.
So antihistamines can be a problem.
Obviously, don’t compromise your ability
to breathe completely, but antihistamines
generally work by blocking what are called mast cells, M-A-S-T.
Mast cells are really interesting cells
that we’ll talk about in our month on neuroimmune function.
They travel in the bloodstream,
and they’re these little packets
that burst open at sites of inflammation.
Muscle damage and inflammation is a signal
that something needs to change,
and so taking antihistamines, it appears,
can disrupt some of that inflammatory process.
So you actually want inflammation
during and immediately after a workout,
then you want to bring inflammation down later,
and I’ll mention how to do that.
The other thing are non-steroid anti-inflammatory drugs.
You know their trade names.
These are painkillers that many people take.
Those, as I’ve mentioned in a previous episode,
can interfere with the benefits of endurance training
and the benefits of resistance training.
In addition to that, they block pain signals,
and pain is a very good signal
that you might be doing something wrong,
and so while nobody likes to be in pain,
I suppose there are probably a few people out there
that like to be in pain, but that’s a different story,
but nobody likes to be in pain,
the non-steroid anti-inflammatories, the NSAIDs,
as they’re called, and the antihistamines
seem to prevent a lot of the gains,
the improvements in endurance strength and size
that people are specifically using exercise for.
So be cautious about your use
of non-steroid anti-inflammatory drugs,
especially within the four hours preceding
or the four hours following exercise.
So I hope you’re starting to get the picture.
In order to change the nerve to muscle connectivity
in ways that will better serve you,
you need a stressor during the actual training.
Which particular stressor depends on your training goals,
but that stressor is almost always going to be associated
with inflammation, and then after the training,
you want to try and get into a state of reduced inflammation,
and that’s why you would do some sort of protocol,
non-sleep deep rest, which we will link to in our caption,
or perhaps you would use the hypnosis app
that we’ve talked about before, reveree, R-E-V-E-R-I.com.
There’s a great app for accessing deep rest states
or the physiological side to try and get the system,
your system to calm down after training.
There are also tools that one can use to reduce inflammation
at a kind of foundational level away from training.
And these are tools that I’ve talked about
many times before, but I’ll just restate them again.
The kind of golden three, according to Andy Galpin,
and the ones that he recommends are sufficient omega-3s.
Again, that can be accomplished through diet,
through whole food intake, or through supplementation,
or both, so in general, getting above 1,000 milligrams
of EPA per day to keep inflammation low or relatively low.
Vitamin D, and in some cases, magnesium malate.
Magnesium malate seems to be particularly effective
in offsetting delayed onset muscle soreness.
Soreness itself is not required
for improvements in strength,
improvements in explosiveness, improvements in hypertrophy.
That’s a myth.
Now, if you do experience delayed onset muscle soreness,
chances are you stressed that particular muscle pretty well,
or even maybe too well.
Maybe you stressed it too much and you need longer recovery.
There’s a total debate out there
about whether or not you should train again
when a muscle is still sore.
I think the general takeaway is no,
that means it’s not recovered.
And there are things, of course, like massage,
like fascial release, and things of that sort,
sauna, cold, that can perhaps accelerate
the movement from soreness to not sore.
But in general, the omega-3, vitamin D,
and magnesium malate trio seem to be an effective way
to reduce inflammation at kind of a systemic level.
But remember, you want inflammation
provided you’re not damaging the muscle so much
that you’re injured during the training session
because that’s the stimulus for change in those muscles.
I want to talk about a few other things
that support the process of nerve to muscle communication
and touch on some of the things
that a lot of people are doing
to try and quote-unquote enhance their workouts
and evaluate whether or not those are, in fact,
enhancing workouts or not.
Because weight training,
unlike a lot of other forms of exercise,
has a unique aspect to it,
which is this feature that I guess
some people call it the pump,
which is the fact that blood goes into the muscle
when you train.
It’s the only kind of training
where you actually get a window
into what the result might actually look like
before you actually accomplish that result.
So if you think about when you go out for a hard run
and let’s say you go out for a two-mile run,
let’s say your goal is to break,
you want to do a sub-10 two-mile.
Actually, when I went to university,
I was running cross-country my senior year of high school
and I wanted to walk on for the cross-country team.
And so I went out there
and it turned out you had to do a sub-10 two-mile.
And I think the best mile I ever ran in high school
was a 457, which isn’t terrible.
I can’t do that now.
It’s not even close to what high school athletes,
the best high school athletes can do now.
But that would have meant doing it back-to-back.
So a sub-10 minute two-mile didn’t even come close.
I told Costello this story the other day
and he just kind of laughed at me.
He was like, why would you even want to run two miles?
Because Costello is built almost exclusively
of these type two fast twitch muscles.
They’re designed for moving objects.
He’s incredibly strong.
He has been since he was a puppy.
I mean, that dog could probably drag a tractor
if he wanted to, but he can’t really go far.
Whereas a greyhound or a whippet
or some of these other sight hounds or scent hounds
can go, go, go.
They have a higher percentage
of the so-called slow twitch muscle fibers.
They are much better at endurance.
So a sub-10 two-mile would have been very, very challenging.
No chance I could have done that, I don’t think,
even with a lot of training.
But let’s say that you want to improve your performance
in a given type of exercise.
Let’s talk about some of the things
that seem to work across the board
to improve strength, improve hypertrophy,
and improve nerve to muscle communication and performance.
The first thing that’s absolutely key
for nerve to muscle communication
and physical performance of any kind
might not sound that exciting to you,
but it is very exciting, and that’s salt.
Nerves, nerve cells, neurons, communicate with each other
and communicate with muscle by electricity.
But that electricity is generated by particular ions
moving into and out of the neuron.
And the rushing in of a particular ion, sodium, salt,
is what allows nerve cells to fire.
If you don’t have enough salt in your system,
your neurons and your brain
and your nerve to muscle communication will be terrible.
If you have sufficient salt, it will be excellent.
How much salt will depend on how much water you’re drinking,
how much caffeine you’re drinking,
and how much food you’re ingesting.
So, and whether or not you’re taking any diuretics,
how hot it is, et cetera, how much you’re sweating.
So you want to make sure that you have enough salt,
potassium, and magnesium in your system
if you want to perform well.
I realize that salt isn’t a very glamorous performance tool,
but it is vital.
It is absolutely vital.
And the endurance athletes
and the people that train in high heat
can speak to the fact that when your electrolytes are low,
your brain doesn’t function,
your body doesn’t function nearly as well.
In fact, even for mental work,
for studying and for writing and for doing math and coding,
doing analytic work of any kind,
even a hard conversation that’s important to you,
having sufficient electrolytes is really going to help
and being low on electrolytes won’t help.
And just drinking water won’t help
because you need electrolytes.
The other thing that’s been shown over and over again,
in numerous well-controlled studies
to improve muscle performance is creatine.
Early on, there was a lot of controversy about creatine,
but there are many studies.
If you want, you can go to this website
that everyone now knows I love,
which is this free website, examine.com,
that there are no fewer than 18 studies there, 66 studies.
So 18 studies supporting that muscle creatine content
can be increased by ingesting creatine.
How much creatine?
Well, I asked the experts,
and they tell me that for somebody who’s about 180 pounds,
five grams a day should be sufficient or so.
Heavier than 180, so if you get like,
if you’re a 220 pound or 230 pound person,
10 to 15 grams of creatine.
People lighter than 180 pounds,
maybe three to five grams of protein, excuse me, creatine,
or even one to three grams.
Creatine is a fuel source for early inbouts of activity,
for high intensity activity.
It is also a fuel source for neurons in the brain,
and it can have some cognitive enhancing effects.
So creatine is a very interesting molecule.
Early on, when it was released as a supplement,
it was thought that you had to load it
in higher dosages for a few days
and then maintain it at lower dosages.
So you’d take 20 or 30 grams a day,
then back off to five or 10.
It doesn’t seem to be the case
that you can get all the benefits
from taking the dosages at the low level.
I just mentioned a few moments ago
as they relate to body weight throughout.
So salt and electrolytes, absolutely key.
You need those present.
You need to be well hydrated.
Creatine seems to have a performance enhancing effect.
There are 66 studies, 66,
showing that power output is greatly increased,
anywhere from 12 to 20%.
And this is sprinting and running and jumping
as well as weightlifting by creatine.
The ability to hydrate your body is improved by creatine
because of the way that it brings more water
into cells of various kinds.
As an indirect effect, it can help increase lean mass
because of the way that it brings more water into muscle
and probably also because of the way
that if you get stronger,
you can generate more force and generate more hypertrophy.
It reduces fatigue.
Seven studies have shown that it reduces fatigue.
There are even some interesting effects
on improving cognition after traumatic brain injury,
although that’s a serious medical condition in situations,
you absolutely should talk to a board certified physician
before adding anything
or taking anything out of your current regimen.
There are a few other effects
that are interesting and notable,
but the big ones are the ones that I referred to before
about increased power output, et cetera.
And I just want to emphasize
that creatine can increase this hormone
that we talked about in the testosterone episode,
which is testosterone converted by 5-alpha reductase
It’s the more dominant androgen in humans,
leads to increases in strength and libido and so forth.
It also can increase male pattern baldness.
Some people, not everybody,
experience some hair loss with creatine.
Other people don’t.
Some people experience accelerated beard growth
because basically DHT has the opposite effect
on hair follicles on the face as it does on the scalp.
Some people don’t.
Women who ingest creatine,
there are essentially no data showing
that it increases hair loss or facial hair growth,
but of course, everyone is different.
So you can go to examine.com.
You can explore those studies.
So creatine, definitely a powerful
performance enhancing molecule.
The other one, one that personally I’ve never tried,
but that seems to have a very strong
and well-supported effects is beta-alanine.
Now, beta-alanine is interesting
because when you hear about weight training,
you think about heavy deadlifts and bench presses,
all that kind of stuff that people are doing.
But beta-alanine seems to support exercise
that is of slightly longer duration.
So a mix of anaerobic and aerobic type movements.
So things, these are physical performance
in the 60 to 240 second range.
So you can use your mind and kind of figure out,
you know, like things that weights of the,
that limit you to eight to 15 repetitions.
Cardiovascular exercise of the sort
like rowing or sprinting.
So interval work, it seems to help with that kind of work.
So we’re not talking about long runs.
We’re not talking about heavy deadlifts.
The standard dose is somewhere between two and five grams.
Again, as always, check with a doctor,
make sure these things are safe for you.
I’m not responsible for your health.
You are, I don’t say that just to protect me.
I would say that also to protect you.
But it really seems to improve muscular endurance,
improve anaerobic running capacity, reduce fatigue.
There are even some interesting effects
on reduction of body fat and improvements in lean mass.
So creatine, beta-alanine, electrolytes.
These are kind of the core three things
that seem to improve performance
and are well supported by the scientific literature.
And in the earlier episode on supercharging performance,
we talked about Palmer cooling.
That’s certainly a performance enhancing tool.
It’s nothing you ingest.
You’re cooling your palms in a very specific way.
That’s very powerful.
Now, what about for longer duration bouts of exercise?
We’ve mainly been focusing on resistance training,
but what about for long runs, long swims,
these kinds of things?
Well, it does seem that beet juice
and ingesting things like arginine and citrulline
can improve performance for those long bouts of exercise.
That’s mainly going to be due to effects
of those compounds on vasodilation.
It’s going to open up the vasculature
and allow more blood flow.
Do note that things like citrulline and arginine
can have some side effects, if you will.
They can increase the likelihood
of having herpes cold sore outbreaks on the mouth.
The arginine is in the pathway by which,
I don’t know if people know this,
but the herpes virus lives on neurons
of the trigeminal nerve that innervate the lips
and the eyes and the mucous membranes of the face.
So this is the herpes type one simplex virus.
The virus lives on those neurons
and then periodically inflames those neurons,
and that’s what leads to the cold sore.
It seems like arginine and citrulline
can lead to increases in cold sores
and canker sores and outbreaks of those kinds.
So you want to be aware of that.
That’s not everybody, and not everybody is carrying HSV-1.
Just be aware that I think it’s now 80 or 90% of people,
by time they’re 12 years old, they’ve contracted HSV-1.
It’s very contagious.
And typically people will get one outbreak
and then only under conditions of stress
or heightened arginine or citrulline ingestion
will have them later.
Again, this is not necessarily a sexually, an STI.
This is a sexually transmitted infection.
This is an infection that is passed very easily
from mucous membranes,
just in terms of touching objects and things of that sort.
Very common in the general population.
Any discussion about muscle and muscle performance
would not be adequate
if we didn’t mention something about nutrition,
but rather than have a whole discussion about nutrition,
because there’s lots of information about that online,
like for instance, if you want to gain muscle,
that you need to have a caloric surplus
of about 10 to 15%.
You could have a caloric surplus of more
if you want to avoid gaining weight,
then you would not create a caloric surplus, et cetera.
You can find all that information online.
That’s not what this podcast is really about.
We had a month where we talked a lot about hormones
and food and moods.
We talked about foods,
but more as they relate to the nervous system.
When it comes to supporting muscle,
to supporting the synthesis of larger,
what I called myosin balloons,
it does seem that ingesting 700 to 3,000 milligrams
of the essential amino acid leucine
with each meal is important.
Now, that does not necessarily mean from supplements.
In fact, most people recommend that you get your protein,
you get your amino acids,
including your essential amino acids
and your leucine from whole foods,
high quality proteins, high density proteins.
What do you mean by that?
Well, it is true that a lot of sources of protein
are found in things like beans and nuts
and things like that,
that all the essential amino acids can be found there.
But per unit calorie, if it’s in your practice,
if it’s in your ethics to ingest animal proteins,
it’s true that for instance,
200 calories of steak or chicken or fish or eggs
will have a higher density of essential amino acids
than the equivalent amount of calories from nuts or plants.
That’s just simply the way it works.
So I’m not, for the vegans and vegetarians,
I’m certainly not saying there’s no way
that you can support muscle growth.
You absolutely can.
Some of them might want to supplement leucine,
but this 700 to 3,000 milligrams of leucine per meal
is one of the best ways that’s been shown
to support the synthesis of more myosin
if your goal is hypertrophy.
And it’s also the way that you would support muscle repair
if your goal is strength.
So that’s specifically geared
towards muscle hypertrophy and strength.
And I encourage you to think about this
protein density issue
and whether or not you ingest animal proteins or you don’t
to think about whether or not you’re getting
sufficient essential amino acids, especially leucine.
Now, many people have addressed the question
of whether or not you need to eat six or seven times a day.
It turns out that you don’t.
That’s kind of the old school thinking
that you need to eat very frequently.
I think for certain athletes who are very active
meaning people that are enhancing their testosterone levels
to super physiological levels,
where they are experiencing very heightened levels
of protein synthesis and they can utilize all that,
that might make sense.
Again, I’m not supporting the use
of those performance enhancing drugs,
but there are people doing that.
And that’s one of the reasons why they eat so frequently
and so much protein.
For typical people who are not doing that,
I imagine most of you are not,
then it does appear that you need to eat,
but you don’t need to eat six or seven times a day.
It does seem like not eating once a day is also important.
So somewhere between one meal a day and six meals a day
lies the more reasonable two or three
or maybe four times a day.
I think that a whole discussion about this is warranted
and we’ll have this discussion with Dr. Galpin
at a future time of how,
whether or not eating protein more frequently
can enhance this myosin synthesis.
But I think the simple takeaway from the literature
that I was able to extract and from my discussion with him
is eating two to four times a day,
making sure you’re getting sufficient amino acids
in a way that’s compatible with your ethics
and with your nutritional regimen
is going to support muscle repair, muscle growth,
strength improvements, et cetera, just fine.
There’s one more thing that I’d like to cover,
which is the relationship
between particular kinds of exercise
and our ability to think and perform cognitive functions.
We all hear that exercise is so vital for our brain
that it supports our brain health and our body health.
And indeed that’s true, provided it’s done correctly.
However, many of us are familiar with the experience
of going for a run or going for a swim
or working out hard in the gym
and then not being able to use our brain
to be essentially useless for cognitive functions
for the rest of the day.
I discussed this with Dr. Galpin this morning
and I learned something very interesting,
which is that hard bouts of exercise
of the sort where you’re training near failure
or you’re generating focused muscular contractions
for a session that lasts anywhere from, I don’t know,
30, 45 minutes, maybe 60 minutes,
or a long run where you’re engaging
in some interval training during that run.
there’s a reduction in oxygenation of the brain.
So there’s actually a quite significant dip
in the amount of oxygen that your neurons are getting
and therefore your ability to think.
So it’s important that you control the intensity
and the duration of your training sessions
so that you’re still able to do well in life
and lean into life the way you need to,
because I’m guessing most of you are not in a position
to just prioritize your physical training.
You also need to use your minds.
I’m certainly familiar with wanting to get exercise,
but also the requirement of needing to perform
cognitive work throughout the day.
It also turns out that you can leverage something
interesting about exercise and nerve to muscle work
in ways that can benefit cognitive function and focus.
And it has to do with the way that your body
and your nervous system predict bouts
of intense focused effort.
So let’s say you’re doing resistance training
two or three times a week, maybe even four times a week,
and you’re doing it consistently at a given time.
There are clocks, literally biological clocks
within the liver and within the brain
that learn to predict that focus and that intense work.
If you are trying to get intense cognitive work done,
you might try scheduling that cognitive work
on the days when you don’t do physical training
at the same time when you normally would do
that intense focused physical training.
Because the systems of the body that generate
acetylcholine release and other neuromodulators,
the systems of the body and brain
that generate focused effort,
those are on this sort of clock mechanism
in a way that you likely will find
that after just a week of training at regular times,
you will be able to focus readily on other things
when you’re not training,
provided you do it during the period of time of day
when you normally would train.
So this is kind of an indirect positive effect.
You’re harnessing the focus and the expectation of focus
in your nervous system for that particular time of day.
And of course, we’d be remiss
if we didn’t talk about time of day for training.
Turns out that whether or not you do,
whether or not you train in the morning or in the afternoon,
doesn’t really seem to matter
for sake of things like hypertrophy and strength, et cetera.
Everyone seems to have a time of day
that they prefer to train.
I’ve said before,
and there are reasons based on body temperature rhythms
and cortisol release that training 30 minutes,
three hours or 11 hours after your normal waking time
can be very beneficial
and can provide a sort of predictability or regularity
to when your body will be ready to train
and best apt to train well.
There is some evidence that training in the afternoon
is better for performance,
whereas training for body composition changes
and strength changes, et cetera,
doesn’t really matter when you train.
So you also want to make it compatible with sleep,
compatible with work.
That really gets down into the weeds of optimization.
But I think it’s interesting to note
that if you’re going to train at a regular time,
you can take the days when you don’t train
and use that to enhance your cognitive focus
for things that have nothing to do with exercise.
So this might be writing or reading
or music or math, et cetera.
Typically, I restrict these podcast episodes
to about 90 minutes,
so-called ultradian cycle for learning.
Today was a bit longer.
And I admit that I tried to pack a lot into this.
It is the last episode in this month
on physical performance.
I figured in this case, more is better,
especially since everything is timestamped for you.
You certainly don’t have to watch it all at once.
And you can come back to it over and over again
and to the precise locations in the episode that you like
in order to take notes
or extract the information that you need.
I’d like to point you to Dr. Andy Galpin’s page.
I highly recommend looking into the work that he’s doing
if you want more details.
He’s very, very skilled, excellent communicator.
He’s superb at what he does.
He’s a professor.
He works with athletes.
He works with typical folks
in the exercise and muscle physiology world.
Brad Schoenfield’s work, I also have a lot of respect for.
I’ve never met him.
I don’t know him.
There’s no paid endorsement here.
They’re not sponsors or related to the podcast in any way.
I just think the work is of very high quality
and they are both on the academic side
and the practical side.
And of course, there are other people out there
doing fabulous work in this area as well.
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The way this podcast is set up,
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So the episodes on sleep, for instance,
that were way back in January,
what seems like way back,
are still every bit as relevant today
as they were back in January
for somebody that has challenges with sleep
and wants to understand sleep and get better at sleep,
or wants to understand their dreams
or how to use sleep and dreaming
to leverage neuroplasticity and learning.
So if you pass information along about the podcast,
And as always, please put your questions
about the podcast episodes
and suggestions for future episodes
in the comment section.
I really do read through all those comments.
It takes me some time, but I do read through those.
I reply to as many of them as I can,
but I do read them
and they’re a great way for us to get feedback.
On Apple, you can give us a five-star review
if you think we deserve that.
And if you want to do all these things you’re welcome to,
if you want to do just one of them, we understand.
And if you do none of them,
we still appreciate that you come here
to digest the information
about science and science-related tools.
And as mentioned at the beginning of today’s episode,
we are now partnered with Momentus Supplements
because they make single ingredient formulations
that are of the absolute highest quality
and they ship international.
If you go to livemomentus.com slash Huberman,
you will find many of the supplements
that have been discussed on various episodes
of the Huberman Lab Podcast,
and you will find various protocols
related to those supplements.
Last but not least,
I want to thank you for your time and attention today.
And as always, thank you for your interest in science.