Dr. Andy Galpin: How to Build Physical Endurance & Lose Fat | Huberman Lab Guest Series

[Music]

welcome to the huberman lab guest Series

where I and an expert guest discuss

science and science-based tools for

everyday life

I'm Andrew huberman and I'm our

professor of neurobiology and

Ophthalmology at Stanford School of

Medicine today's episode is the third in

the sixth episode series on fitness

exercise and performance today's episode

is all about endurance and fat loss that

is the specific protocols required to

achieve the four different kinds of

endurance and how to maximize fat loss

Dr Andy Galpin great to be back

today we're going to talk about

endurance and I'm very interested in

this conversation because I like many

other people strive to get a certain

amount of cardiovascular work in each

week

maybe a long-ish jog maybe a swim ride

the bike Etc

but when I think about the word

endurance the idea that almost

immediately comes to mind is about doing

something for a long period of time

repeatedly but I have a feeling that

there are other ways to trigger this

adaptation that we call the endurance

adaptation so I'm excited to learn about

that I'm also excited to learn about the

fuel systems

in the body that allow for endurance and

other modes of repeated activity so in

order to kick things off I'd love for

you to frame the conversation by telling

us

what is endurance and are there indeed a

large variety of ways to induce what we

call this endurance adaptation sure the

way I want to start actually here is is

calling back to some of the things we

talked about our previous conversations

which are really people exercise for

three reasons number one you want to

feel better

number two you want to look a certain

way and then number three you want to be

able to do that for a long time right so

you need the way that we say it in

sports is look good feel good play good

right so I want some sort of

functionality to be able to perform a

certain way whatever that is for you you

want to be able to look a certain way

that whatever that matters for you and

then you want to be able to do that for

a long time so when it comes to

endurance we have a bunch of misnomers

here which is the same thing with the

strength training and resistance

exercise side where we wanted to dispel

this myth that

I lift weights only because I I want to

gain muscle or play a sport and I want

to do cardio because I want to leave

their loose fat or for long Health sake

and just like we smashed that myth from

the strength training side I want to

smash it from the endurance training

side there are so many other reasons

that you want to perform endurance

training

regardless of your goal right whether it

is longevity whether it is performance

or whether it is Aesthetics and so we're

gonna I want to cover all those reasons

uh exactly what to do Protocols of

course and why those things are working

that way in general though the quick

answer

is really endurance comes down to two

independent factors Factor number one is

fatigue management and then Factor

number two is fueling and that's all it

really comes down to so all the

different types of training are going to

reach a limitation which are either

again your ability to deal with some

sort of fatigue and that's generally a

fatigue signal the other one is

managing some sort of restriction of

energy input and a lot of the spoiler

here is a lot of the times people think

it's a fueling issue and really it's a

fatigue management issue or the opposite

and to have a complete Health Spectrum

regardless of whether you're a high

performance athlete like I typically

deal with or general public you need to

be able to do both manage fatigue as

well as understand fuel storage so

that's really what we're going to get

into today fantastic I can't wait before

we dive in I'm going to ask you what I

often ask people who are expert in their

respective fields which is is there any

non-obvious tool or mechanism or tool

end mechanism that can allow people to

access better endurance you know when I

think about training for endurance again

I think about trying to run longer and

longer each week yeah or Swim further

and further and so on but I do wonder

whether or not there are other forms of

training that can amplify the endurance

adaptation

that I or most people perhaps don't

think of as endurance sure the way I

want to answer this is if we look back

and think about how we've answered that

question with power and strength in

force production it is really about how

much can you produce

maximally once

what you're asking now is how can I

repeat that same quality of performance

if that's the case endurance really

comes down to your ability to maintain

proper mechanics

that's going like the biggest way we can

and increase your endurance

exponentially very quickly is mechanical

and this is starting with breathing and

so we need to be breathing properly we

need to have proper posture and

positions and then we need to be moving

well efficiency is going to Trump Force

always

for endurance

the other side of the equation is not

that you can have a little bit of leaks

in your mechanics and still squat well

or jump high and be fine because you

don't have to suffer those consequences

repeatedly right that's going to drain

you over time so the quickest way to

improve endurance is to improve

mechanics and the mechanical thing I

would go after first is your breathing

techniques your pattern your entire

approach as well as your posture and

then from there the third one would be

your movement technique is it possible

to describe the best way to breathe when

doing an endurance training or is it far

more complex than that and if it is far

more complex than that then certainly we

can get into it during today's episode

yeah it is both of those I will give you

a quick answer though a lot of the times

you can

kind of Hit the cheat code which is

nasal breathing there's plenty of times

when you don't want to nasal breathe you

don't need your nasal breathe but just

again is that like a one tool that is a

for a pretty General answer if you can

do that a lot of the times that will fix

breathing mechanics just by default and

we can maybe talk about why that is

later but that would be my sort of one

sentence bullet point answer immediately

of how to get in the right positions the

second one would be simply looking at

your posture right so whether you're on

a bike or you're doing a lift or you're

running if you're literally uh hunched

over and your ribs are touching your

femur or getting closer and closer like

tends to happen on a bike or an air

assault thing for somebody I've seen

recently this morning I was on the

assault bike um doing a Sprint and I

asked Andy Dr Galpin to critique my form

and anything else he wanted to critique

so that I could improve and he did

comment on my rather c-shaped posture

correct um encouraging me to be more

upright which I should probably do now

as well and he also cued me to the fact

that during a one minute Sprint there is

something that is quote unquote magic

that happens right about the 42nd Mark

and I use that as a

um as a milestone uh to look for and

indeed something does happen at the 42nd

it's into a one minute Sprint where all

of a sudden it it does seem to get much

easier for reasons I don't understand

maybe you can to tell it that but it

certainly had nothing to do with my

posture my posture needs Improvement

thank you well yeah so

um breathing mechanics and breathing

strategies uh people tend to be over

breathing early on and this is going to

lead to problems later so having a more

strategic breathing pattern and approach

is again a very quick solution I know

that we're going to dive very deep into

the mechanisms of Energy and Metabolism

and endurance today but as long as we're

having a discussion about these um

briefs or tidbits of how to improve

endurance are there any other ways to

improve endurance that that are of

relatively short time investment even if

they require a lot of um energy

sure the classic Paradigm you're going

to find here is steady state long

duration

posed up against what a lot of folks

will now call higher intensity interval

training specifically and there's a lot

of misconceptions here the quick answer

is you need to be doing both and there's

probably a bunch of stuff in between

that you should be practicing if you

honestly want to maximize those three

factories we talked about at the

beginning you need to be training across

this full spectrum just like I told you

to train across the full spectrum of

your lifting we want to be doing the

same thing here so are there independent

special factors that can happen with the

shorter time length higher intensity

stuff absolutely there's also magic that

happens on the other end of that

Spectrum so it's very important that

people don't just choose one side

because what tends to happen is people

either go with the oh I'm going to do 30

or 45 minutes of steady state stuff

that's it or I'm gonna do the opposite

which I'm going to leave that stuff on

the table not do it because I only want

to do high intensity intervals because I

can get it done in five minutes so

there's Magic on both sides of the

equation we want to get into all that

but just to answer your question

directly

there's a whole bunch of of things you

can do

um in under one minute that are

convenient to do and there's a wonderful

set of papers out of a couple

Laboratories in Canada that that

championed this idea that's called

exercise snacks so there's a bunch of

there's a series of studies that have

been done here that are really

interesting and they've looked at a

couple of things that are noteworthy one

of them is a 20-second bout of all out

work and this is actually done in

workers in an office and so what they

have them do is run upstairs and I

believe it was about 60 steps is what it

took them something along the order of

20 seconds exactly and they repeated

that about once every four hours

so really it's you go to work you get

you know put your coffee and your bag

down whatever you run up a flight of

stairs 20 seconds later then you go

right back to work at lunch and before

you go home you sort of repeat it there

and if you repeat that that's multiple

times a week you're going to do that I

think they in one of the interventions

it was three times a week

for six weeks 18 total times you did

that

and what you'll see is a noticeable

Improvement this is statistically

significant improvements in

cardiorespiratory Fitness specifically

VO2 max as well as a number of cognitive

benefits work productivity

Etc that can happen in as little as 20

seconds you don't have to go to the gym

you don't have to shower you don't have

to do anything like that just find the

stairs run up and down them a few times

now you may have noticed um you actually

sort of caught me yesterday I did that

right here right I was just I we had a

little bit of a break I was feeling an

energy lull I ran up the stairs three or

four times felt a lot better so that can

actually also help they ran another

study where they looked at that

following a giant high glycemic index

meal and what they saw and then they

took insulin measures and a whole bunch

of

um other biological markers Associated

that you want to pay attention to the

high glycemic index meal and they looked

at those immediately an hour three hours

six hours as opposed and it was very

clear that same intervention was able to

improve post-planned yell glucose

control insulin and a whole bunch of

other factors in addition to that so if

you are the sort of type who's like wow

I'm in an office all day maybe also had

a giant high glycemic index meal not the

best approach but a little bit of

mitigation there can just be running up

a flight of stairs or doing something

like that for as little as 20 seconds so

there's a lot of magic and power and

maximal exertion

if one does not have access to a flight

of stairs at work could they do jumping

jacks absolutely I mean you could do

anything you really wanted it's not the

mode of exercise that matters here it is

simply the exertion you just get up as

hard as you can you could do burpees you

could do any number of things you could

Sprint down your road down the hallway

back and forth the mode is is just uh

something that was easy for the

scientists to control and X number of

steps people could do it you're not

going to fall hurt yourself things like

that just to remind me it's once every

four hours one minute of all 20 seconds

oh 20 seconds excuse me uh 20 seconds of

essentially all out exertion yep while

remaining safe not going so fast up the

stairs or doing jumping jacks certainly

not down the stairs

up the stairs please

um escalators don't count well I suppose

they count if they're uh you know if

you're if you're moving uh if you're not

remaining on the same steps

um in fact in an airport recently I saw

somebody walking against the oh there

you go the conveyor yeah while talking

on the phone while waiting for their

flight to take off and I thought it's

genius right it looked a little awkward

who cares yeah but it was I have looked

awkward in every airport I've been in

for the last 15 years for those exact

reasons doing wild stuff like that yeah

well nothing's more Awkward than not

being able to walk to the end of the

terminal simply because one isn't

familiar with walking that far carrying

a couple of suitcases there you go yeah

that's the the other fit test the

suitcase carrier yeah I'm in the airport

I love this so once every four hours 20

seconds so maybe once when arriving to

work once four hours in and then four

hours most people probably work

somewhere you know eight plus or minus

two hours now one thing I actually

really want to make clear because your

audience is so incredible

um

they tend to be really excited about

these protocols and they follow them

exactly as written that's not exactly

how science works so it doesn't

necessarily have to be every four hours

it's in half three three times a day it

doesn't have to be 20 seconds they

literally built that protocol because it

was so they're trying to replicate a

real life scenario maybe you're in an

office building you're generally there

for eight hours Let's see if you did one

every sort of so if you want to do it

four times a week great if you can do it

only 10 seconds amazing you're probably

going to get the same benefits those are

not the details to pay attention to the

detail to pay attention to is every so

often multiple times a day

try to get your heart rate up really

quickly it doesn't require sweating

doesn't require anything else there's no

warm-up associated with it again you

need a minute break in between meetings

or whatever and you can Sprint up them I

do this all the time in my house when

you you know have those days when you're

on like seven straight hours of zooms

Etc you can get out of 20 seconds I run

to my garage which is over there I hop

on the the airbike and I will just smash

out 30 seconds as fast as I can and then

walk right back in

love it yeah

I'm gonna start yeah just also you can

just put one of those things which I do

also just put one in your office

and hop over right over there you know

the whole entire thing now literally

takes 23 seconds before we begin I'd

like to emphasize that this podcast is

separate from my teaching and research

roles at Stanford it is also separate

from Dr Andy galpin's teaching and

research roles at Cal State Fullerton it

is however part of our desire and effort

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tell me about endurance what is

endurance how do I get more endurance

and how does it work

when we think about endurance I would

like to open up the conversation to

include more things than people

generally do when they hear the word

endurance so if we just think about what

you typically ask your body to do or

would like to ask your body to do and we

just walk through them

it's going to be things like this number

one I want to have energy throughout the

day that's actually a form of endurance

great I don't want to have these lulls

and fatigue and I want to feel fantastic

as I move throughout my activities of

daily living whatever those may be work

exercise

enjoyment paying attention focus all

that stuff great that's one thing

another thing you want to ask your body

to do is I want to be able to repeat

some small effort in a muscle group and

not and feel great about that this is

what we generally call muscular

endurance so this is something like I

want to be able to walk up those 10

flights of steps and my quads aren't

burning at the end of it right or it

even gives me energy another thing

you'll want to ask your body to do is to

be able to perform a tremendous amount

of work

for a longer period of time something in

the realm of you know 20 to 80 seconds

so this could be something like if

you're surfing and you've got to paddle

extremely hard for a minute to get on on

top of a wave or you want to you got

you're out riding your bike and you need

to be able to get up a hill and it's a

very Steep Hill these are going to take

maximal efforts for some small amount of

time and then you'll get back up there

we tend to call that maximum anaerobic

capacity so that the max amount of work

you can perform at a higher rate for

some amount of seconds to like maybe a

minute

past that is your ability to repeat an

effort kind of like that for something

like 5 to 15 minutes and this example

would be run a mile right some some

interval like that which is a longer

distance right that is going to be your

maximum aerobic capacity

okay

another thing you're going to want your

body to do is we call sustained position

so this is you want to be able to sit in

your chair at work and have perfect

posture for 20 30 40 minutes right you

want to be able to stand in line at a

grocery store for 15 minutes and not

have a breakdown in posture so you want

to be able to maintain position when

you're riding your bike you're not

collapsing you're doing any of these

activities and you don't get hurt

or lose efficiency simply because you

couldn't sustain basic positions all

right whatever those shapes and

positions need to be

okay and then the last one is a maximum

distance so you won't be able to go for

a longer hike or have just a long day at

Disneyland for whatever it needs to be

and feel great at the end of it right so

the goal with all of these things is not

can you just do them but can you do them

and then you feel good afterwards so

we're back in a right position where

they give you energy you feel good about

it and it's not just something you had

to do and you regretted and you felt

awful so those are the factors I think

about when someone says I want better

endurance is I want to walk backwards

and say okay when you say endurance what

do you mean and that's generally the

things I've come across as if you can

handle all of those things you're going

to feel like you're in fantastic shape

you're going to feel your recovery is

going to be excellent and your physical

performance in the gym or in any of the

sporting activities you do will be

enhanced given what you told us a little

bit earlier that endurance really

reflects fatigue and management and

energy production

how do each and both of those things

relate to endurance at a mechanistic

level so really what I'm asking is what

is fatigue management and what is energy

production in order to do that it's

important that we understand all of

those functional capacities that I just

talked about

they all have different points of

failure

okay so in order to then work backwards

and say well how do I optimize my

performance in all those categories we

need to go through each one and figure

out where am I failing some of them are

going to be failing because of fatigue

management and some of them will be

failing because of energy production

issues so if we walk through a little

bit of how we make energy and how we

handle fatigue then we're going to have

a better understanding of exactly what

to do for each one of these categories

if you feel like one of them in

particular is worse for you or lagging

behind or if in general you just want to

improve all of them all right now I want

to make a little bit of a 90 degree turn

here

I'm going to do it with strategy though

I promise and I want to ask you a very

simple question

how do you lose weight

I was taught that the calories in

calories out

thermodynamics of energy utilization

governs most everything that is if I'm

ingesting

less caloric energy than I burn

then I'm going to lose weight and if I'm

ingesting exactly as much as I burn I'll

maintain weight and if I ingest more

then I burn

then I'll gain weight sure that is the

approach you would take

what I'm asking really is how are you

actually physically losing the weight

so my understanding is that we have

different fuel sources in the body

glycogen

which is stored in muscle and liver body

fat which is sort of mainly white

adipose tissue and which is subcutaneous

and around our organs intra visceral fat

and that we can also use protein as a

fuel and then as I recall there's also a

phosphocreatine system and I think

you're going to tell me that each of

these systems is tapped into on

different time scales and perhaps

according to different levels of

exertion and I'm certain that what I

just said is not exhaustive but

hopefully it is most or entirely correct

pretty correct what's that got to do

with fat loss

at some point body fat stores adipose

adipocytes fat cells are going to start

liberating fat as a fuel source

and the stimulus for that I'm assuming

is going to be that other fuel sources

are either depleted or that the energy

and metabolic systems of the body

I don't want to say decide because they

don't have their own Consciousness but

are um our flip signals are signaling in

a way that registers that body fat would

be the optimal fuel source given how

long

or into and or intensely a given

activity has been performed okay we have

some stuff to clean up there but we're

still not really answering the question

how am I actually losing that body fat

uh how is it actually leaving the body

correct uh my understanding is that it

leaves the body through respiration aha

so now we have some interesting things

to talk about

how am I actually losing fat via

respiration what the hell does that even

mean how is something that occupied this

physical space on the side of me leaving

my body through my mouth

and that is a very clear answer there

right which I'm sure you're queued up to

when you take a breath in you're

generally breathing in oxygen O2 that's

some other things but we'll just stick

to oxygen when you exhale you're

breathing out CO2 the difference between

those two is that carbon molecule well

one of the things that's important to

understand here is all of your

carbohydrates which is that word itself

is a carbon that has been hydrated so it

is a carbon molecule attached to a water

molecule it is a simple chain of carbons

your fat molecules are also chains of

carbon all of metabolism really in terms

of energy production is simply trying to

figure out a way to break those carbon

bonds as a result we get energy from

that we use that energy to create a

molecule called ATP which is the central

source of energy for any living being

right that carbon is then floating

around in free form which is bad news

internally so we've got to figure out a

way to get that carbon out of our system

so all of energy production all of

fatigue management really comes down to

this core issue of how are we handling

carbon and how are we moving it around

the body and so what we do is we do this

sneaky thing so another question I'd

like to ask people is why do we breathe

well

for two reasons uh to bring oxygen into

the system and to offload carbon dioxide

but the neural trigger for breathing is

when carbon dioxide hits a threshold

level and the set of neurons in the

brain stem and elsewhere uh activate the

phrenic nerve or the gas reflex or a

combination of things and we inhale or

inhale right so a reduction of oxygen

intake generally doesn't stimulate

ventilation unless you're at altitude

then that sort of changes right in

general it's an elevation in CO2 that's

going to stimulate breathing off the

only reason you bring in O2 for the most

part is to get rid of the CO2 oxygen is

not a fuel source

it is not a way and it works the same

with fire by the way so you know you

have to have oxygen present for a fire

to go and if you use quelch oxygen the

fire will go out right that's about half

of

um how those like fire extinguishers

work but we think then that means oxygen

is the fuel it is not the fuel it is

something entirely different it is a

necessary Pro it is a product that is

necessary for the metabolism process to

actually occur all right so we're kind

of dancing around an idea here which is

this carbon cycle of life

so what happens in plants is they

generally will breathe in the opposite

and breathe out the opposite of humans

so a plant will breathe in CO2 and

exhale O2 all right this is why we have

to have a certain amount of these things

and algae and forests and trees and

stuff to maintain this O2 CO2 balance in

our atmosphere we do the opposite so we

have this wonderful circle of life we

breathe in O2 breathe out CO2 they do

the opposite well what happens is

because carbohydrates are long chains of

carbon and fats are as well generally

when we think about fats by the way it's

important to understand that structure a

little bit so if we think about

triglycerides it is a three carbon

backbone chain of glycerol so one two

three and horizontally running off of

each one of those are fatty acid chains

right so we form this structure that

looks like an e right like the letter e

three in the back and then three chains

coming off of it each of those chains

are called fatty acids and each of those

fatty acids are a length of carbon right

or a number of carbons strung together

however many carbons are there

determines which type of fatty acid it

is right so stearic acid linoleic acid

like any different number of things it's

also what determines whether or not it

is a monounsaturated or polyunsaturated

as if carbon requires a special thing

called a double bond so if there's a

double bond across every carbon and

carbon then they're all fully saturated

and you're great if there's any of them

that are not double bonded and in fact

an example if there is one that doesn't

have a double bond that is now called

Mono and saturated if there are many it

is called polyunsaturated

so there's pros and cons to all these

things right in either case we're still

talking long carbon chains so what a

plant will do

is bring in carbon and then it has this

wonderful ability to use energy from the

sun called photosynthesis and it can

take those carbons that it inhales and

use the energy from the Sun to form a

bond now in our prior discussion when

we're going over hypertrophy we talked

about the energy that was required to go

through protein synthesis that's because

forming a new atom or a new bond between

atoms oftentimes takes energy in this

cases it does the same thing happens

here so if a plant does not have oxygen

or does not have carbon dioxide in the

air it has no fuel the basically think

about it is that's what it eats it needs

to get nitrogen from the ground in the

soil just like we need to get nitrogen

from our protein but fuel wise it needs

to get carbon dioxide then it needs sun

to give it energy so it can actually

form that Bond right that's what it's

getting its fuel from

all right so if we think about

um a classic

uh plant produce the plant that produces

either a starch or a fruit here's what

happens

it inhales that carbon and it starts

packing it away now in a root vegetable

what it does is it stores those things

together and if we store that thing and

we grow fruit at the bottom of it we

tend to call those things starches

all right it's going to then take the

carbon that is packed away in its root

and send it up the tree and it's going

to actually do that by breaking it down

into a smaller form of carbohydrate that

we tend to often call things like

sucrose and glucose it'll ship that up

the tree it'll go out to the leaves and

it'll convert it into the fruit and it's

going to eventually transform that stuff

into smaller carbon things called

fructose and if we think about the fruit

are the sugar in fruit it's often in the

form of fructose or sucrose or a

combination and sometimes glucose so we

have these smaller carbon six carbon

chains generally in the form of glucose

that are being made from this larger

storage of uh carbohydrates that we call

um starch right so it's packed in

together

your body does the exact same thing so

if it's a potato

and it has a whole bunch

of glucose packed away we call that

starch if it's in your quadricep and we

pack about a whole bunch of glucose Away

We Now call it glycogen if it's in your

blood as that six carbon chain we call

it glucose if it's in the tree and in

the fruit we call it fructose right

those are different molecules but that's

effectively the same thing happens so

the biology or the chemistry is almost

identical it just runs in the reverse

order and that's why again at tubers and

potatoes and stuff tend to be starches

and fruits tend to be glucose fructose

of sucrose so we have this

a wonderful Circle of Life the plants

can survive on just breathing in the CO2

and then getting the energy from the Sun

we don't have that ability at least to

my knowledge to run through

photosynthesis so the only way we can

get carbon into our system is to

actually ingest carbon which means we

have to eat the starch the fruit

the animal some other form of stored

carbon to get that into our system

we then pack that away we put the

carbohydrates as you mentioned earlier

either on our liver

our blood or in our muscles we put the

fat generally in adipose tissue we'll

put a little bit in muscle cells as

intramuscular triglycerides and then the

protein will use as structure right to

do different things we don't like to use

protein as material or fuel it's better

used as structure and what we have to do

then is if all of a sudden we realize

that storage is getting too much in our

body in other words we're gaining too

much weight we have to figure out how to

get the carbons out of our body

and that is metabolism right anytime

we're trying to break a carbon bonds

though we can get energy to make ATP

that's going to release the carbon out

of our tissue into the blood we have to

bring in oxygen to bind that carbon

molecule to make CO2 so we can exhale it

and put it back into the atmosphere it's

a beautiful description of the circle of

life and

energy utilization in the human body

I have to ask the question that I'm sure

many people are wondering about which is

if indeed we exhale these carbons and

as it relates to Fat Loss that is the

way that we lose fat if we're in a sub

caloric state for instance

has it ever been explored as to whether

increasing the duration or intensity of

exhales can accelerate fat loss I mean

that's sort of The Logical extension of

what you described and here I'm actually

interested equally in whether or not the

answer is yes as well as whether it

could be no because I could imagine if

the answer is yes well then there's some

interesting protocols to emerge from

that but that if it's no it will reveal

to us some important bottlenecks about

metabolism and energy utilization you

ever seen those magicians who like show

up and uh they can tell your mom's name

or something like that before you

because they can sort of hold you down a

path yeah I mean not to take us down a

deep dive tangent but I once went to the

Magic Castle in Los Angeles and I was

one of the people called up front and a

in an incredible magician a named um I

think his name was Ozzy mind or

something uh I think that's right had me

write my name on a card

in a Sharpie pen I ripped up the card I

ripped it up I put it in my pocket

and at the end of the 10 or 15 minute

bout of him doing a bunch of other

tricks

he asked me to look in my right shoe and

under my foot in my right shoe was that

card intact yeah and it was no longer in

my pocket and I swear in my life I

wasn't a a collaborator with him and to

this day it still gives me chills

because it well I I don't know how magic

yeah right magic well the reason I say

that is I've given that little Spiel and

I just gave you the countless times on

my glasses and I would say 99 of the

time as soon as I stop the very first

question is

so can I just like

do a bunch of exhales and lose fat which

is wonderful because I was really hoping

you would do that and you rolled right

into my trap right you landed perfectly

so I look like a like a a magician over

here I feel like I should look in my

right shoe right now no I asked the

question because it's the logical

extension of what you laid out but

I know biology to be um both uh

diabolical and cryptic but also

Exquisite in the way that things are

arranged and you don't get something for

nothing there are no free passes in

physiology that's the saying no free

passes the answer to your question is

yes

100 yes in fact that is the only way to

go about it you have two options you can

ingest less carbon or you can expel more

carbon people always say calories in

calories out it's really carbon in

carbonate

that's what a calorie is Right calories

the amount of energy we get per breaking

a carbon Bond so it's really Less in

less more out less in is fairly obvious

whether that comes in any form and by

the way

this is exactly why the percentage of

your intake coming from fats or

carbohydrate it doesn't really matter

that much if you look at fat loss

clinical trials you guys may have

covered this when Lane was in here I'm

sure like this is something he talks

about a lot it doesn't matter it's

irrelevant because it's not about that

there's nothing magic in those things

they are different they have different

physiological responses everything is

different right no duh but in general

it's just simply about carbon intake

turns out fat has a lot more carbons per

mole than carbohydrates do so there's

more calories per mole in there so if

you the physical amount of fat needs to

come in as a smaller amount physical

amount of carbohydrates these are coming

it will come in as a larger amount but

you can play

any number of very high carb low fat

what matters total calories right again

it's not like the only thing that

matters but you know what I'm saying

some percentages in the way can go fat

loss Works fantastic high fat low

carbohydrate why why do all these things

work because that's not about that it's

about total intake of carbon total Expo

so absolutely can you lose fat by simply

exhaling more in fact that is exactly

what you did this morning

when I hopped on the airline bike when

you did anything

right the question is can you think of a

scenario in which you could have a bunch

of increased rates of exhalation

that helps in Fat Loss sure I can think

of a lot of things that will stimulate

increased rates of exhalation one thing

could be simply going

right and so the question is like can I

literally do some breath protocols where

I force exhale and lose fat and the

answer is yes

but what happens what happens if you do

hyperventilation training well my lab

studies cyclic hyperventilation is one

of our many uh deliberate protocols and

one of the most prominent things that

one observes is that levels of

adrenaline increase very quickly

extremely quick people feel jittery

anxious stressed and unless they are

consciously trying to Anchor their

thinking about what that means and the

benefits that to persisting typically

they abort the cyclic hyperventilation

protocol really quickly within seconds

right you will feel tingling sweating

all kinds of things you're

hyperventilating right and we could we

could talk a nauseam about how that

changes everything from adrenaline to

focus to a whole bunch of things so

unfortunately a strategy of sitting

around just exhaling more than you

inhale

technically helps you lose more fat but

it's not going to last very long so then

the question is well how do I get no

situation or scenario in which I can

increase my rate of expiration

where I'm not going to pass out I'm not

going and altering hypocapny and

hypercapnia issues

any idea of a situation in which you

would have an enhanced rate of

explanation without worrying about

passing out

sure a steady state exercise or not

steady state exercise lifting weights

intervals moderate training repeated any

of these things they all work equally

for fat loss because all they're doing

is increasing respiration rate they're

saying increased demand for energy

increased exhalation

that's the trick here and when you

equate these things to that they have

equal success in fat loss

it doesn't matter theoretically

where you're getting it from and so when

we get into this idea of well what are

the best training strategies for fat

loss

it doesn't matter which one of these

tactics you pick

as long as you maintain a consistent

adherence over time

because of this exact fact it doesn't

matter if you're burning quote unquote

fat in the exercise session or if you're

burning carbohydrates in the exercise

session it is totally irrelevant to your

net fat loss over time okay now there's

some significant misconceptions there

about what I just talked and I would

love to come back and walk through that

in more detail but that's the main

take-home message here

it won't matter what's coming in and it

won't matter what's coming out because

in either case it is the same rate of

oxygen in and CO2 out that's the key

metric and hopefully this helps a lot of

people have some relief because they're

like man you're so tied up on what is

the exact protocol for training for

optimizing fat loss what's the exact

nutritional intervention I need for fat

loss and then you wonder why all these

different diets can work effectively and

wonder why all these different training

protocols you know surely you know

somebody who lost a bunch of weight and

the only thing they did is they just

started running

there was no Advanced protocol they just

started running and they ran five miles

every day that works and then tons of

people who tried that and like didn't

lose anything and lots of people who

went to I went to cardio kickboxing

class lost weight oh I just started

doing intervals on my law why why

mysteriously you'll do all these things

work

they had you have something had some

spidey sense have to has to be going off

in your brain where like there has to be

something linking these things

and what's linking it is simply carbon

Exchange

so put yourself in a position in which

you are exhaling more than you and

inhaling without passing out

the other problem is if you were to

Simply do a breathing protocol

while the rate of exhalation would go up

after that you would correct and go in

the opposite direction so that's the

problem is your net carbon the output

over the course today is not going to

change unless you increase the demand

for energy and that's how you get into

that negative state

along these lines of exhaling carbons as

the route for fat loss

it makes me wonder whether or not

increasing lung capacity is possible I'm

guessing the answer is yes and whether

or not

increasing lung capacity is a good goal

and route to enhancing fat loss

essentially what I'm asking is if you

can offload more CO2 okay carbons per

exhale

are you a more efficient fat loss

machine it's a wonderful thought and the

answer would be no

not something you worry about because

if you were to Exhale more

carbon than actually needed

now we're in a state of inefficiency

you're burning way more energy than

needed to do your activity the heart has

a metric called cardiac output this is

in Sciences we abbreviate this as Q

for some odd reasons it's either seal or

q and cardiac output

is heart rate multiplied by stroke

volume so it's how many beats per minute

you're having as well as how much

blood's coming out of it so cardiac

output is actually

very specific to energy needs if you try

to work around that it's just going to

adjust itself so what I mean by this is

if you were able to increase your stroke

volumes the amount of blood coming out

per pump you would automatically adjust

reduce your heart rate so that you keep

cardiac output

exact to energetic demands so you're

sort of pushing one end of this of the

spectrum but your body will pull the

other one back to keep you at that exact

same neutral level so if you look at if

you think about like cardiovascular

adaptations to endurance training and

any type of endurance training a common

thing people will understand is resting

heart rate and so what that number is is

just how many beats per minute you're

having when you're sitting here doing

nothing a very positive adaptation is a

lowering of that resting rate over time

as general numbers what you will hear is

people will say things like a normal

resting heart rate is between 60 to 80

beats per minute and you know if any of

the things I've talked about

um with the individuals I work with I

don't work with anybody with disease

just to clarify that I don't do anything

with disease management treatment

anything it's always about people who

are in a good spot

who want to optimize or get to the next

level whether this is professional

athletes trying to to Peak for physical

performance or uh the folks in our rapid

Health optimization program that feel

good again it's not disease stuff and

they want to feel incredible

one of the metrics we're going to pay

attention to is this resting heart rate

so here's what happens as you improve

your endurance

your resting heart rate will go down if

I see somebody over 70 beats per minute

um unless something's going on you're

not physically fed

regardless of whether or not that is

quote unquote within the normative

values I want to see everybody's sub 60

beats per minute or close right and that

does not a difficult thing to really get

to for most people so if you train a lot

regardless of how you train intervals

steady state

doesn't matter that resting heart rate

will come down but since energy demands

at rest haven't really changed cardiac

Alpha stays the same so what happens is

stroke volume goes up so literally like

we trained your quadriceps on the Legacy

engine machine to get stronger so you

can produce more Force per contraction

the heart will do the exact same thing

and so as you're able to get more of the

blood out of your heart per pump

the heart realizes I don't need to pump

as often

so that's the compensatory adaptation

which is saying hey look I don't need to

beat 60 times a minute I now need to

beat 55 times a minute because I'm

getting the same amount of Blood Out per

pump chill and this is why your resting

heart rate goes down your resting stroke

volume goes up but your cardiac output

is identical so that's not a good metric

of Fitness it's going to stay the same

cardiac output will only adjust for

energetic changes all right energy

requirements in the acute moment right

how much do I need go which is going to

be determined by ventilation right how

much air am I bringing in and putting

out that's going to determine cardiac

output and that's going to determine

where we're at if you were to do like a

sub maximal exercise test

when you were unfit to when you're fit

or when you're fit the way you're super

fit at sub Max you're going to see the

same thing

cardiac output will be identical and

you're like damn nothing happened what

you're not realizing is your heart rate

at that same workload is now lower

and that's efficiency because your

stroke volume is higher where it gets

people tripped up is at Max

because you may not see much of a change

at Max because you won't really you

don't really see an increase in maximum

heart rate with Fitness that's not a

thing right so maximum heart rate is not

a good proxy for fit or unfit or

anything like that stroke volume will

get limited eventually by filling

capacity of your heart it has to have so

much time to fill up with blood before

it can contract again and squeeze the

blood out and when you have a heart rate

of 200 beats per minute that just

doesn't leave much time to fill and so

it won't really push you past that so

don't worry about trying to increase

your maximum heart rate that's not

necessarily a good thing and it won't

really change but your cardiac health

will because stroke volume will be

higher but that doesn't necessarily mean

that I should avoid training that gets

me up toward maximal heart rate correct

oh you should absolutely do it right

that's what that was my assumption I'd

like to take a brief break and

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special offer getting back to energy

production and metabolism

so we've got these different modes of

moving energy but making and breaking

energy Bonds in the body moving energy

into different tissues and out of

different tissues and indeed out of the

body through exhalation

how do each of these different modes of

energy utilization

relate to different modes of movement

and exercise yeah in my mind I'm

starting to draw a bridge between

okay when I walk for 60 minutes

you know if I'm talking I'm breathing a

bit more maybe I'm burning a little more

fat after all speech is a modified

exhale

um and amazing if I'm sprinting

um breathing differently and if I'm um

you know doing a 30 minute moderate

quote unquote moderate jog breathing

differently so you've beautifully

Illustrated this bridge between energy

production and utilization and carbon

dioxide offload through exhalation

what are some of the specifics about

energy utilization

according to different modes of exercise

and if we could better Define modes of

exercise or types of exercise that

trigger specific adaptations I think

this is where the the bridge will move

from being a a mere line to a real

structure yeah absolutely I want to lay

one more foundational piece and then

it's going to be much easier to

understand

the limitations I put on some of these

training protocols as well as the lack

of limitations okay so it's really

really important the way I want to start

this is

we have this this Foundation now of of

carbon and and basic energy production

that's not to say there's no difference

there is and that difference is

important but maybe we can answer the

question from earlier which is

actually something you asked me this

morning when we were exercising

you're like training fasted

right does training fasted

enhance fat loss

and the logic is sound if I don't have

any fuel then I should be burning more

fat therefore I should be losing more

fat it's sound it's not true

is this great idea it's one of these

classic things in science and exercise

physiology where like sounds good

turns out it's not it's actually a

pretty gross misunderstanding of

metabolism

so it's not to pick on that topic I

don't really care about that topic but

it is a it's a common question it also

gives me an opportunity to just tell you

more about metabolism so

here's what happens

you're breathing in O2 and breathing out

CO2 however the ratio to that is what we

call the either rer respiratory exchange

ratio or RQ respiratory quotient and I'm

not going to differentiate those two

they're not the same thing but we're

going to skip past that for now as you

begin to increase exercise intensity

the percentage of o2 to CO2 rises in the

favor of CO2 so you start breathing out

way more CO2 than you are breathing in

O2 right and so if we were to look at

that number you know once the

relationship Echoes up so at rest most

people have a of a value that we would

typically call something like 0.6

okay and that's again the relationship

between O2 and CO2

maybe 0.7 if you were to go for a walk

that increases slightly because you're

now expiring CO2 at a higher rate so now

you've moved up to say 0.8 or something

like that one of the ways that we Mark

somebody of achieving an actual VO2 max

on a test is if that value exceeds 1.1

now any of you who are paying attention

are thinking wait a minute how the hell

can a ratio between two things ever get

past one

well that's because you're getting in a

place where you're actually offloading

more CO2 than is actually necessary and

this is what actually causes and

explains a thing that people like to

call Epoch which is excess exercise post

oxygen consumption this is another way

to think about it

the only reason you're breathing is to

bring in oxygen when offloads CO2

right

if I'm no longer exercising why am I

still breathing

in other words once you stop the demand

or the need for for energy you should

stop ventilating

but you don't

right that's because in the case of low

intensity exercise the second you stop

you're right back down to resting

ventilation no problem because you were

able to match the need for energy with

the offload of waste one to one during

that exercise when you start creeping up

the intensity you can't do that so you

have to basically start stealing a

little bit of fuel here so even though

you're done exercising you're still

ventilating because you have to pay that

back and pay that back by that I

specifically mean you have to bring in

oxygen because you have a whole bunch of

waste that's been accumulating in your

tissue that you've got to deal with and

I'll walk you through what that waste is

it's a particular molecule that a lot of

people have heard of but grossly

misunderstand

so you got to be able to handle that so

the reason that you sit there and go

and continue to ventilate is because

you're now trying to pay back that

excess post exercise oxygen debt that's

that oxygen debt we're specifically

talking about all right so

that being said as we start cruising up

that RQ starts going up up up up up up

up and if we get to one your 1.0 you're

you're in a like you're hurting you're

in a pretty good spot all right I like

that you're hurting you're in a pretty

good spot yeah a window into Dr Annie

galpin's mind now you really want to be

a subject in his uh his laboratory study

sure

masochists swarm to Andy's lab

absolutely all right

so

the idea that I will lose more fat

by being in an exercise situation that

is burning more fat it seems to make

sense but it's a massive failure to

understand the metabolism it's the exact

same explanation to like exercising

fasted doesn't matter so the exercising

fasted issue under normal circumstances

is irrelevant because you have plenty of

fuel in the system even when you haven't

eaten breakfast that morning now if

you're talking like extended fasting

over multiple days this is a different

scenario if muscle glycogen liver

glycogen and blood glucose are at

sufficient levels then you absolutely

have enough energy to perform almost any

type of exercise that most people are

doing

you know maybe if you're Rob and you're

at Mile 20 today it's a different story

but the vast majority of us have plenty

of fuel sitting around so we're not

going to burn more into fat

um just because we didn't eat breakfast

that morning so that just doesn't make

energetic sense we have a lot of backup

supplies you're never out the trick here

is this is there's a there's a concept

here we call crossover concept so as we

are starting to move up exercise

intensity

we start burning a higher percentage of

our fuel from carbohydrates and a lower

percentage of our fuel coming from fat

I'm sleeping

that's the highest percentage of your

fuel that will be coming from fat of any

activity you could ever do so if the

theory that I'm going to stay at a lower

intensity to burn more fat was true the

optimal fat burning strategy would then

be to sleep

like that doesn't make sense of course

it doesn't so why would then going at a

slightly elevated rate somehow all of a

sudden magically make you lose fat

it doesn't actually make sense when you

think about that where you're like oh

yeah there's no way

so

it's a percentage trick it's a

difference between absolute and relative

this is what this confusion is so yes as

you start doing lower intensity exercise

whether you're faster than audit it's

irrelevant but lower intensity exercise

a greater percentage of your fuel

is coming from fat however your total

fuel expenditure is very low

so that whole total carbon balance is

not really being shifted much

as you start exercising at a very high

intensity you actually start getting a

higher percentage of your fuel from

carbohydrate and a lower percentage from

fat in fact at rest about the highest

you can get in most people is about 60

of your fuel from fat

as you're sleeping you might be 70 but

you'll never be in a position ever no

matter what sort of thing you've heard

on the internet you'll never be in a

situation where fat is your only fuel

source

the highest I've probably ever seen is

like 70 percent

um you should probably beat about that

that's a kind of a good number to think

um honestly but people will understand a

little bit about metabolism to be

dangerous but not enough we'll we'll

throw out these terms like fat adapted

and fat adapted is a real thing but is a

massive misunderstanding oftentimes

right it is this idea thinking like I

can get into a spot where I'm maximizing

fat burning maximizing fat burning

and maximizing fat for exercise and

maximizing fat loss over time are not

the same thing at all right that's the

confusion so if you enhance fat

oxidation and exercise that does not

enhance fat loss

per se

right so this is a lot of the confusion

that's happening

right so as we start moving up we can

never get in a position where we're

using fat only as a fuel again at best

you're at 70 fat 30 carbohydrate for a

lot of reasons we probably just don't

have time to get into today

however the opposite is possible when

you get into true high intensity

exercise you'll be basically 100

carbohydrate and zero percent fat all

right that is very possible that in fact

is 1.0 that's what our Q 1.1 is actually

because your ventilation got so high you

actually exceeded that number even

though you're at 100 carbohydrate this

is what people came up with the idea

then it's like whoa I don't want to burn

carbs I want to lose fat

so my response to that is always like

okay great

so it makes sense burning fat losing fat

burning carbs is losing what then

like you think your liver shrunk like

wait a minute what did you lose then

where'd it come from it's all coming as

carbon don't worry about where it came

from for your fuel

it just has to come out as carbon

right there are differences in exercise

efficiency for performance with our

professional athletes of course but if

the only goal here is phallus it doesn't

matter where you get it from

the last Bridge we have to connect here

is like well wait a minute if I only

burned carbohydrate

how did I actually lose that fat there

was there was that love handle sitting

on the side of me how did that come out

of me if I never burned that from my

fuel what you're failing to understand

is there's a balanced game that happens

here so if you were to do a bunch of

high intensity exercise training

and you burned only muscle glycogen and

blood glucose and maybe even you did it

for so long you burned some liver

glycogen

the body understands that it has

expelled a lot of energy

from that side of the equation it's

going to do a couple of things now it's

very difficult

to go through this fancy situation where

you convert carbohydrates into fat and

back and forth like that's actually like

fairly hard what's easier to do with

something you said earlier is actually

just bias energetics to a different fuel

source so in that scenario where you're

down really low in your carbohydrate

carbohydrate stores

any carbohydrates you bring in are going

to go to storage

and since your net energy expenditure is

something that your body regulates a lot

any fat that you then bring in is going

to be utilized as a fuel source because

it knows it doesn't need it anymore that

is in excess so that's how you actually

use fat

as a fuel because you've burned down

carbohydrate storages

as I'm hearing this uh a couple of

things come to mind first of all

thank you for that incredibly important

description of what is otherwise a very

confusing landscape for most people one

of the key points I took away and

I just want to say from the outset this

is not exhaustive by any stretch is that

burning fat does not equal losing fat

from the body correct and then burning

fat has to be divided into burning of

body fat stores

and we need to distinguish that from

burning of dietary fat that is brought

in correct oftentimes people don't

disambiguate those correct

and I'm also understanding that

reducing one's body carbohydrate stores

muscle glycogen liver glycogen Etc

occurs during high intensity exercise

yep as well as other ways but that is

one very efficient way to tap into those

stores which makes me wonder

again this is one of these things that

does it lead to a protocol

makes me wonder whether or not doing

high intensity let's say weight training

for 45 to 60 Minutes 75 minutes of

strength training power training

hypertrophy training which we've covered

in an episode about those topics

and then doing some steady state

cardiovascular exercise is there any

benefit to that arrangement

that would quote unquote enhance

body fat loss from the body to be very

specific now

because unlike the idea that training

fasted would shift the bias towards fat

loss which it doesn't you've told us

under those conditions muscle glycogen

and maybe even liver glycogen is going

to be depleted

put simply can I enhance body fat loss

by doing some cardio after a bout of

weight training if you equate for total

energy expenditure it won't matter

now that you did bring up a very

important point that I want to clarify

if you look at the exercise modalities

that we laid out in our previous uh

conversations we talked about nine

different adaptations one was skill and

then speed power strength hypertrophy

muscular endurance anaerobic capacity

aerobic capacity and long duration

endurance

speed

power and skill development

have almost no benefit for fat loss

because remember those are low weight

a lot of rest and low volume

they're not really really going to be

helpful you can make a little bit of a

case for strength

a little bit but the total energy

expenditure for strength training even

if it's an hour if it's truly strength

training it's fairly low because the

repetitions are in the one to three

range that's exactly it's not enough for

total work so if you're trying to

develop a protocol that sort of

optimizes fat loss what you want to do

you were close in my opinion is do a

combination of something in the

hypertrophy slash muscular endurance

strength training realm okay so

um six to Thirty repetitions something

like that resistance training great

deplete muscle glycogen maybe even a bit

of liver glycogen maybe a little bit

depending on if you're doing it for a

long time but probably not a noticeable

amount okay so an hour of of uh

hypertrophy type training if you're

training hard with low responsibils and

you really did an hour you would for

sure get there but most people don't

because the reason why I crave large

bowls of oatmeal and rice after I do

weight training yeah and replenish

muscle glycogen totally right

um then you maybe do a little bit of

very high intensity maximum heart rate

well overview to Max uh hard as you can

for 20 30 45 60 seconds something like

that with some recovery

a lot of recovery and repeated and

that's going to do a great job of

replenishing muscle glycogen right if

you do that long enough you'll get the

liver but again most people don't

because it's really really hard to go

that hard so liver is sort of last Last

Resort yeah basic mechanics here which

will which we'll actually get into as

our like third segment here

is

energy production comes from the local

exercising muscle first and foremost

from phosphocreatine and carbohydrate

stores right and so again and we store

it in a muscle we call it glycogen right

that's it's your first sign of light on

defense if you need

glucose outside of that you're going to

start pulling it from the blood but one

of the things your body regulates a

handful of things over almost everything

blood pH blood glucose blood pressure

and electrolyte concentrations like it

really does not want to mess with those

things at all it will change almost

anything else in the body to keep those

things standardized right you generally

because you need all those things for

your brain to work and your brain will

stop working right if you lose blood

pressure it won't go up there pH changes

you can't run metabolism electrolytes

change you can't think and glucose is a

primary fuel source for the brain it's

going to be a problem right so if that

number starts to come down because

you're grabbing glucose out of the blood

your liver is going to then kick in it's

going to break down its glycogen to put

glucose in the blood to keep the blood

number the level in fact one of the

things you'll see is blood glucose

concentrations rise during exercise they

don't fall in fact they rise as an

anticipatory state if you train a lot

your blood glucose will start going up

before you start moving it knows it's

coming right so you you can play that

game you can rob Peter to pay Paul for a

long time and tell your liver runs out

and that's what actually is a bonk in

terms of like long duration endurance

stuff you're talking many many miles

several hours typically we say oh it's

got to be over two hours

before your liver starts to become a

real problem or it has to be

tremendously intense because of those

reasons you have to burn through just a

lot of energy before your liver starts

to get into a problem you can continue

to train when your muscle glycogen

levels are low

in fact people say glycogen depletion

and muscle but it's it's generally

misnomer and you are going to have

tremendous signals of fatigue when that

number gets lower than 75 percent

so people think that like their muscles

are getting heavy you're probably still

75 full a lot of folks will quit around

the 50 the highest I've ever seen is

like 95 true depletion and that's an

extremely high level cross-country

skiers and like they're deltoid it's

very very low some very talented Runners

will get fairly low in their quads but

the vast majority of folks by the time

you're 50 depleted you're gonna quit

it's going to be really really

challenging so you're never really going

to get that low it's like a bit of a

protective mechanism right but when your

liver gets low

you're going to be shut down and that's

the case of if you've ever been to like

a marathon and you've seen people run

like 25 and a half miles and then they

just like Bonk they go into like baby

deers walking stands and then they

collapse and you're like how are you

mentally weak like you ran 26 miles and

you can't run the last point it ain't

mentally weak it is if your liver is

done it's gonna stop you because there's

no more backup reserves muscle you can

get away with you can push through it

liver will not let you go any farther I

find this fascinating because it makes

me wonder whether or not the liver being

depleted sends a neural signal to the

brain or the brain must register some

signal like I would like to be alive

tomorrow thank you whatever is happening

right now

um stopping is going to be safer than

continuing yeah and so that stop signal

um is is one that I think a lot of

people including myself are are

intrigued by because we always think

that it's uh related to willpower but

the brain needs to preserve itself and

as the master computer I mean there are

ways to go into kind of automaton type

um you know not thinking just doing type

uh Behavior you have override switches

right and you can play those cards and

you can get better at learning and be

being less sensitive to that switch

that's exactly what happened when you

first start training right you start to

realize like oh my gosh I'm super tired

then you realize really quickly like oh

I'm totally fine here and this is like

the

pick pick your person who's made sayings

like this but it's like you're really

only 10 percent depleted or 30 or 40 or

something we're all operating 40 of what

we could do of course any of those

things are true because it is like a

little bit of an override um you've just

gotten very sensitive to being a small

percentage depleted and you've learned

okay I'm tired and there is a long way

to go past that but once you get past

that and you flip that override switch a

lot

um you just you're going to break

quickly because you basically learn to

ignore that signal and problems can

happen really quickly after that and

that's even experienced endurance

athletes if you hit that level

it's like you're going to be hitting the

concrete next and that's you know

potentially a problem

I want to make sure I understand a

concept that you referred to earlier

correctly because I have a feeling that

I don't and that's this issue of

how the body accesses body fat stores

when in a sub caloric State and I'm

doing mainly glycogen burning exercise

yeah

what I heard you say and please correct

me where I'm undoubtedly wrong

what I heard you say was that okay I go

into the gym and I start

lifting weights I'm burning muscle

glycogen mostly local to the muscles

that I'm using and then I start pulling

glycogen from the bloodstream

maybe there's some

body fat stores that are mobilized

probably not dipping into my liver

glycogen

okay I complete the workout maybe I even

hop on the air dime bike and do a little

Sprint yeah go for a jog maybe

um I eat immediately afterward maybe I

don't eat for a few hours afterwards but

across the day I ingest fewer calories

than I burn

is it the case that body fat is

mobilized in order to replace the

glycogen that my sub

caloric intake

was insufficient to provide in other

words because I didn't eat enough to

fill the glycogen stores

am I using body fat

converted into glycogen to fill those

stores right

and if so is that a case where I'm no

longer exhaling carbons in order to burn

body fat but rather I'm repurposing body

fat into muscle have I turned fat into

muscle in that case yeah I'm really glad

uh you asked this because I did a very

poor job on that last Point talking

about earlier I'm realizing playing back

in my head because that's so many really

good questions you cannot turn fat into

muscle

can you turn muscle into fat no I'm so

glad you said that because when I was in

college yeah our I don't want to out

that person the physiology teacher

seem to think still at that point that

one could lift weights get muscular but

then it would eventually turn into body

fat that that I that myth has I think

largely been dispelled I heard that so

many times

as a kid I heard it so many times in

college I heard it so I hear it so many

times in our

uh undergraduate students from other

faculty and such so

um no like they're not the same

structures they are very different um

let me take you out on answering this

better you're really really close so

yeah

if you were to do that type of exercise

where you've burned a lot of muscle

glycogen how is it I'm losing stored fat

right that's really the Crux of the

question and it doesn't even actually

matter if you then went ahead and

ingested carbohydrates or fat post

exercise

that's not really a thing you hit on a

couple of key things number one this is

all under the assumption that total

caloric intake

is still low right you have a total need

it's below okay

I also want to flag calories in calories

out is not the only thing that matters

this is a very complex thing calories in

is incredibly complicated calories out

is even more complicated okay so we just

maybe another series we can spend on

that alone all right so don't don't go

nuts about that

you have to be hypocaloric one way or

the other if you burn a bunch of muscle

glycogen and you are hyper caloric

you're still going to add fat

if you burn a muscle glycogen and you're

hypochloric you're going to lose fat

right think about it this way

you're in a negative calorie state

where are those calories going to come

from are you going to reduce your muscle

glycogen storages permanently no no are

you going to reduce your glycogen

storage in your liver

no you want to reduce blood glucose no

no way right so where is that extra

energy coming from it's coming from your

stored fat it is your backup Reserve

Energy System um the way that I want to

fly this here is people tend to think

about it as like carbohydrates versus

fat that's not it's more like a chain

more like a bicycle where there's a

front gear and a back gear you turn one

gear it turns the other one these are

complementary systems they are not and

or systems right you're turning one and

when we go through carbohydrate

metabolism maybe here in a second you'll

understand why you have to have an

anaerobic and an aerobic component to

that there is absolutely no way to

complete carbohydrate metabolism without

oxygen that has to happen the only way

to engage in fat metabolism is aerobic

and oxygen there's no anaerobic

component to it there's a fundamental

difference there

so the your carbohydrates are meant to

be incredibly flexible it is the primary

fuel source for a reason your fat is not

meant to be flexible it is meant to be

Unlimited that's the basic point so you

want flexibility over here and an

unlimited capacity over there now I'm

safeguarded against any energetic need

okay I need to run up a hill for safety

cool carbohydrates are there I need to

then run for 17 hours cool fat is there

we want both of these systems you want

to be able to have great energy

throughout the day

you want a slow drip coming from fat you

don't want up and down up and down feel

great up and down awesome you want to be

able to think very quickly and get hyper

focused boom carbohydrates ramp right up

right get it into the brain get thinking

better get thinking clearly fast so we

want all these not just for exercise

purposes for but for activities of daily

living we want an optimal system here

and when people use the terms like fat

adapted they're generally hijacking that

and they're thinking it used to be a

thing we said all the time and like all

of my undergraduate classes for years

and that idea of metabolic flexibility

is using optimal fuel sources and

optimal types not maximizing fat usage

the people have co-opted that term of

metabolic flexibility to be like oh yeah

yeah therefore learn how to maximize fat

burning that's not what that term means

that term means maximizing your ability

to use whatever fuel is optimal in that

time

now I'll Grant you most people

aren't fantastic and using fat as a fuel

source relative to the other direction

but nonetheless the the gold standard

here should be maximizing both

all right finally answering your

question if I were to to burn a bunch of

muscle glycogen how am I losing that fat

well the fuel you're ingesting in that

hypochloric state is going to say hey

look we have a lot of muscle glycogen we

have to replenish so any carbohydrate

that comes in needs to be biased towards

storage

it's got to go into those tissue any fat

that comes in or doesn't even come in

but any fat that we're using for fuel

needs to be utilized for activity

and that's where the caloric expenditure

from fat comes in so you're basically

saying you're

General physiology

the energy for that starts coming from

fat and the energy that's coming in from

carbohydrate needs to be simply stored

and so what you see is your respiratory

quotient changes right the rer is going

is going off and so in the exercise

moment it shot way up for carbohydrates

and shot way down for fat

as the compensatory response it goes the

other direction because your body's

saying we are low on carbohydrates don't

use them for fuel unless we absolutely

have to right so use them for storage

get our fuel

from the fat side of the equation and so

what you're generally going to say is

like oh I'm burning more fat just

sitting around

after things like that and that's not

even taking into the equation the epoch

part which is like it's not actually as

large as people think it is it's fairly

small

but it is it adds up sort of over time

so um does that explain a little bit

better about how you lose fat when you

actually only burn carbs for exercise

you explained it beautifully

you talked about Epoch the post-exercise

oxygen consumption yeah not being that

significant in terms of energy

utilization

even though today we're talking about

endurance and different forms of

endurance I do have to ask whether or

not people consider the

elevation in basal metabolism that

occurs when there's more muscle around

yeah because muscle is such a

metabolically demanding tissue

um you know if is there a

straightforward-ish equation you know if

one adds one pound of of lean muscle

tissue to their body even if it's

distributed across multiple muscle

groups does that equate to a caloric

need of X number of calories per day and

is that because of the muscle protein

synthesis needs of that muscle or it's

glycogen storage needs or both if you

don't have enough muscle you start to

have problems with fat loss it's

difficult challenge if you have enough

muscle and you're just trying to get

extremely large if your ffmi is 24 and

you're 15 body fat adding more muscles

not really going to play a lot in the

equation and here's why

muscle is more metabolically active at

rest than fat but fat is not inert so

fat is still going to burn a small

number of calories muscle burns more but

it's not nearly what people think it is

I'm a muscle guy I'm a muscle

physiologist I would love to get people

to have more muscle for any excuse I can

it's not honest to say that though

you're talking about when I was in

undergraduate we would say numbers like

50 Cake House per day per pound

is what you can look at right so if you

put on a pound of muscle spread across

the body your basal metabolic rate would

go up by around 50 calories per day

I think that number is grossly

exaggerated it's probably a tenth of

that

six to ten calories maybe um it's hard

to know exactly what that number is but

the more recent estimates are are

something like that so now on one hand

you could say oh my gosh that is not

even meaningful the other hand you could

say that's super meaningful it just

depends on time domain you want to put

that out right so if you were to put on

five pounds of muscle and your basal

metabolic rate went up 30 or 40 calories

a day well over the course of a thousand

days

like that actually adds up so you you

could slice this any way you want

um now maybe that number somewhere in

between I don't really know it's not a

field I paid that much attention to

candidly

because it's not a metric kind of like

epoch

um where it's like we used to really

harp on it and now it's sort of like wow

maybe we exaggerated that like honestly

just a bit but to me it doesn't change

the equation much because if you don't

have enough muscle as they describe

there are other consequences that are

going to make fat loss hard and so you

need to have sufficient muscle

if the additional caloric expenditure is

the carrot great if it's something else

I don't really care there's just enough

evidence that you need to have it or I

should say there's enough evidence that

it will really help you in your path

um maybe a few calories here there is

not really the thing especially if you

understand

a normal food item

anything you pick is going to be

probably a couple of hundred calories

one bad food Choice a day well out kick

almost any amount of coverage you got on

adding muscle mass to you so like

you're really stepping over a dollar to

pick up a dime if you're worried about

how many calories you're getting from

adding muscle

um fat loss is going to be about

regulating that carbon intake above and

beyond anything else

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20 off so I've heard about this concept

of metabolic flexibility mentioned a few

times

frankly you're the first person who's

ever explained it to me in a clear and

concise way how do I know if I am

metabolically flexible and how do I

increase my metabolic flexibility sure

there's no specific standard which is

actually a good thing right and so if

you have a level of specificity that you

want or need metabolically then you

don't actually want to be in this Middle

Ground an example would be if you are a

performing in a type of exercise or an

athlete who performs in a sport that is

glycolically dominated you don't want to

be optimally metabolically flexible you

don't want to be super quote unquote fat

adapted you want to be biased towards

the energy you're going to use the same

could be true for the other end of the

spectrum so in those particular cases

it's not optimal

to be equally effective because there

are no free passes in physiology right

your

energy producing systems

will up regulator down regulate

accordingly so you will actually limit

your ability to say maximally utilized

carbohydrate as a fuel if you're trying

to up regulate your ability to use fat

as a fuel and so this is like there's a

saturation point

outside of that Spectrum most people

just say hey like I want to feel great

throughout the day to be able to do a

bunch of different things how do you

know a couple things

there's a lot of biological markers you

can take there's also just some some

practical takes now none of these

markers

by themselves are any sign what you want

to do is probably a couple of them

and then say okay this is maybe a clue

so again it's really important to

emphasize not a single one of these

tests that I'm about to walk you through

automatically means you can't use fat as

a fuel or the other case which is maybe

you're poor using carbohydrate as a fuel

so disclaimers aside

we'll get into a couple of them so

should we think about these as

informative and useful but not

diagnostic exactly what we call this

data inspired or data LED and not data

driven

right okay cool so number one you want

to think about just overall

functionality do you have a reasonable

regulation of your energy throughout the

day now many things could be going into

this which is why these are not specific

Diagnostics but as a basic measure we

talked about blood glucose levels

um you know a lot of people will say

again you want that to be something like

between 80 and 90

um milligrams per deciliter is the blood

glucose level and you can go look at the

the cutoff points for what determines to

be pre-diabetic and type 2 diabetic Etc

um what I can actually recommend um this

is there's a little bit of science here

actually that I'll walk you through but

a lot of this is my personal preference

um I generally want people to be at 85

or lower and that's because of a couple

of things number one there's actually

some papers that showed any uh every

single point increase

above 85 increases your likelihood of

developing type 2 diabetes by about 6

percent

okay great so technically while maybe 90

or 95 or even up to 100 are you know in

the quote-unquote normative values

that's one clue again it's not

definitive by itself doesn't mean

anything

you need to really pay attention to what

increasing by six percent actually means

but it's a data point where I'm looking

at if I actually then see symptomology

and we run you through maybe some

questionnaires ask how you're feeling

throughout the day and we see

uncontrolled energy about so you're a

lot of energy then get really really

tired and swings okay another data point

all right and we may patch a few of

these things together that may give me

some Clues

um that being said

again this a lot of this rhetoric is

used to then scare people off of

carbohydrates and that is I want to be

as clear as possible that is not

not truly

um

the only thing people should care about

right it can be a thing that can also be

unrelated there are reasons you could

have blood glucose concentrations at

this level or energy swings that are

unrelated to carbohydrate ingestion at

all

all right so one test you can either run

in addition to that if you're going to

get blood glucose measured you can look

at some markers we talked about earlier

Richard AST and ALT what we talked about

how you can kind of look at that AST to

LT ratio before you can actually do the

inverse which is look at alt and AST the

kind of normative value there you're

going to look at is like 0.8 I actually

like to see it lower than that and that

alone has been actually associated with

blood glucose dysregulation and so if

you've seen multiple of science again

we're looking for patterns and patterns

and patterns in both in our case

biomarkers symptomology and performance

and now you're if all three of those

things are lining up you may have an

issue so performance wise

a couple of little tests you can run

um ideally you have some sort of

standard workout you do oh and hopefully

it's it's pretty objective so in other

words like uh I run the same 15 minute

Loop every morning for my cardio okay

great how long does it take you to run

that Loop like you could pick whatever

distance it doesn't really matter what's

your heart rate during that thing and

then what's your perceived exertion now

you should be able to do that fasted

with very little drop in performance

okay if you can do that then that tells

me you're fairly good at using a fat as

a fuel source if however the one day you

go to do your standard workout

and you feel awful

fasting that may be another clue that

perhaps you're not very good at dialing

in

that system if your recovery afterwards

in terms of heart rate recovery is very

long it may be another clue that you

have a poor utilization of fat as a fuel

source the inverse can also be true

so if I give you something in the

neighborhood of like 50 or so grams of

carbohydrate

and 30 minutes later your face is

falling off the table that's a good sign

that you're in the opposite you're

actually very very very poor utilizing

carbohydrate as a fuel and the reason I

bring that up is

um that is equally a problem we send we

hear people a lot make comments

um like man I have to stay away from

carbs I crash really hard if I do them

that has a what that actually means is

you're very poor at utilizing

carbohydrates as fuel you're getting a

your uh your sensitivity is way off we

should be able to have carbohydrate at a

reasonable dosage 50 grams and not fall

asleep 30 minutes later or have to run

to caffeine so that is a sign in our

opinion this is again now just my

practical brain telling you is that's a

sign of dysfunction we should be able to

have plenty of carbohydrates through the

day if we choose to if we want to for

any reason now of course if you were to

throw 150 or 200 grams of carbohydrate

in your belly

you're probably going to take a little

bit of an energy hit after that but we

should be able to have a reasonable

dosage and not you know have to fall

asleep afterwards

what is one way that people can enhance

their utilization of carbohydrates uh

for exercise the reason I ask is I think

I fall into that category yep um I do

consume some complex carbohydrates and

fruit post

resistance training and that tends to be

when I'm hungriest for them but

typically unless I'm I've just done some

resistance training I keep most of my

daytime meals relatively low

carbohydrate and then in the evening I

prefer slightly less protein and more

carbohydrate because it has this effect

of

um sedating me a little bit yeah and I

sleep well and I know this runs against

what everyone was taught which is to not

eat carbohydrates late in the day but I

like it because then I tend to wake up

in the morning

with at least as far as I can tell my

glycogen stores not necessarily topped

off but but certainly filled yep um and

I'm able to train fasted in the morning

and my favorite pre-workout is consists

of water and caffeine and electrolytes

and maybe some supplementation as well

but I love training fasted so there's

actually a number of things um

one little sneaky thing you threw in

there is actually the use of caffeine so

that's another sign if if you have to

have caffeine to do your fasted training

that's generally another sign you're not

very good at using fuel so I use

caffeine prior to resistance training

workouts generally I don't need it for

any kind of cardiovascular training yeah

and when I say that it doesn't mean it's

bad

it's just like another clue that's like

okay you should be able to do this

without having to have caffeine to

execute it now using caffeine to get a

better result is sort of different as an

ergogenic aid um we actually use

a lot of high carbohydrate meals at the

end of the day a lot of the times for

our athletes who are cutting weight or

trying to reduce weight so it is a

fantastic way to handle a lot of things

and that idea that if you eat carbs late

at night

that'll increase fat so like that's all

is so old and so well destroyed

scientifically that that's not a concern

um there's just so much data showing in

fact there's so much data on

like eating timing is is uh generally

poorly understood about when you can eat

and what you can eat eating in the

morning

um versus eating at night like a lot of

what we've heard in there is stuff in

maybe we just saved that for sort of

another day because we're going to get

really far down that's about our weekend

yeah but yes I think our plan is to

cover that in an episode on nutrition

um okay which is in this series the uh

the only thing that would add to it is

you know would you hear about ingesting

carbohydrate late at night I should just

say that uh at least in my case I'm

eating the majority of my carbohydrate

unless

I trained yeah resistance trained early

in the day and which guess I I post

resistance training

um in the last meal of the day but for

me that's not really late at night that

last meal is somewhere between 6 30 and

7 30 p.m so it's three or so hours or

something like that before we go to

sleep around 10 10 30 or so yeah so it's

not you know midnight uh bowls of pasta

I've done that too but um but typically

it's not so I think that um people will

be very interested uh myself included in

how meal timing relates to all of this

but

um yeah let's

so how do you improve fat utilization

how do you improve carbohydrate

organization let's Hammer both out

really quickly

um enhancing fat uh utilization is as

simple as doing a little bit of work in

a

either pre-fat ingested state

so anytime you ingest a nutrient prior

to training you're going to bias towards

that nutrient

right which is almost what we were

talking about earlier so if you want to

guarantee you burn more fat eat more fat

prior to a workout now you're not going

to lose fat but what you're what you're

effectively signaling is we have an

overabundance of this fuel

preferentially Target this fuel

now the downside is that may actually

hinder your performance that's typically

only a concern for people at a very high

level

um

fat is a slower fuel source so if you're

relying more upon that your top end is

going to come down a little bit and so

you wouldn't want to use that strategy

prior to race if it is a carbohydrate

dependent race

all right and in fact we actually see

long-term adaptations that would suggest

that so the enzymes responsible for

carbohydrate metabolism will down

regulate and so you'll get worse at that

so not not a great strategy there

carbohydrate be the opposite right so if

you have carbohydrate prior to exercise

you're going to bias more towards that

so a handful of things you can do

if your total caloric intake is simply

managed that's going to take care of a

lot of these problems an appropriate

eating strategy so the types of food the

combinations of food

all those things are going to make your

post carbohydrate ingestion bunk a lot

of those things can go away so there's a

little bit of physiology that has to be

corrected for so it's a little bit

in one hand you can go very deep here

right so the real answer of how we would

do this is if we see a scenario like

that we're going to do a whole set of

analyzes we're going to go full Labs

right probably extensive blood panel

urine saliva stool even and we're going

to figure out where is that glucose

dysregulation coming from so a lot of

people think like oh it's a metabolism

issue it might be it also might just be

a flag that something else is happening

in the body so we're going to actually

work backwards a lot to try to figure

out exactly why that's occurring it may

be as simple as oh you're eating a lot

of your carbohydrates

without any fiber or protein and we know

that that's important because those will

actually blunt the glycemic index like

the rise in blood glucose so it could be

a simple thing of just like oh your

combination of food is doing it it's not

the total amount um it may be something

again more endogenous to the actual

system

uh it could be

um a heart rate issue it could be a

breathing issue there could be a number