-: Now we're going to dig into the actual function
of the mitochondria, talk about the mechanics of how we're
actually taking this resource based stuff like glucose
and carbohydrates, and getting that ATP conversion.
It's going to require me to pull up some of
my artistic ability here.
If we look at this green segment here
as the mitochondria, what we'll look at
is the two major functional pieces within that
that are made up of pieces of their own.
So you saw that ETC thing
referred to in the previous unit.
That's the electron transport chain.
This is actually where the ATP is made.
So, if I have ATP and it's out here.
When I break that down, I'm going to
break that down into ADP plus phosphate, all right.
So I'll have that broken down energy
that needs to be recycled.
What that's gonna to do - is it's gonna come in here
and this electron transport chain
is essentially the thing that is going to provide
the energy that is necessary to recreate the bond
between the ADP and the P - so it's gonna use the resources
within the mitochondria to be able to then add the phosphate
back to the ADP, and then send ATP back out
to the rest of the cells.
So this is the the mitochondria.
Everything around this is the cytosol...
we're inside a cell right here.
So now this ATP can be used by things like
the ribosome, and the lysosome, or muscle contractions,
or whatever may be requiring that ATP.
But, how do we actually get this thing to work?
This electron transport thing - it doesn't happen freely,
it doesn't happen, you know, via magic.
It's going to be fueled by something else
that we call the citric acid cycle,
which is often referred to in this traffic circle type form.
And what this is, is it's a series of reactions
that is going to provide the
biochemical energy needed for
this electron transport to chain.
Or for this electron transport chain to run to do it's job.
So let's walk all the way from glucose or fatty acids
coming in to actual ATP being produced.
So glucose or fats are going to enter the mitochondria,
our glucose, remember, is going to be broken down
into piruvate first, our fatty acids are going to enter in
in a free form, not the triglyceride form,
once they're in there, they're gonna to be
broken down into a cyto coA.
That a cyto coA is going to enter right here
into the step one of the citric acid cycle.
Now there are a lot of steps to the citric acid cycle,
for this particular video, for this particular course even,
it's not important that you memorize all
of the steps for this, so knowing all of the steps
for the citric acid cycle isn't necessarily
going to make you a better trainer per se in this context,
or be able to determine the stress.
What's important to understand is
is this functioning, and how it relates to the big picture.
So we're not going to go into those details yet.
What I am going to tell you is that
for all of the reactions here, is that there is a
corresponding portion of the electron transport chain
that requires either a nutrient or quo factor
that is being created, so the electron transport chain
essentially has four components.
One, two, three...and then the fourth is the actual thing
that connects the ADP to the phosphate and makes the ATP.
So there are three components that are just working up on
building up enough energy to
finally drive the fourth component.
And in order to do that, we have this wheel basically
turning over here, this providing all of the subsequent
substrates that are needed to do so.
Now, in the illustration form this kinda looks like it's a
step by step process, meaning that okay...
step one, step one; step two, step two;
step three, step three.
For understanding it, we're going to talk about that way
but from a visualization prospective,
and to actually understand what's going on
what I want you to understand is we're looking at
this cell that's cut and half and assuming that
this thing is inside and whatever,
in reality this stuff exists in numerous amounts
all over the place.
So there are large, big protein complexes, and you have
a number of each one of these components
like all over the mitochondria.
So these things exist in mass numbers all over the surface
of that mitochondria, and this chemical reaction stuff
is happening in abundance.
So there are lots of places where glucose can jump in
there's not just one starting point.
There's multiple starting points all over the place.
As we get through this whole process,
if everything's working accordingly,
there's this checks and balances
where this thing fuels that thing adequately,
we get the outcome, and there's
minimal waste, minimal stress on the system.
However, what would happen if say this process here
could no longer work - like I was missing a micronutrient.
Or it could work per se, but it just couldn't
work at the same rate that everything else was working at.
If that's the case, what's gonna happen is
then there's also gonna be a block right here
on the electron transport chain where
it's not able to proceed.
So when we look at the electron transport chain,
we have essentially these three groupings,
these three components.
And the reason we call it an electron transport chain
is it transfers electrons.
For those of you guys that haven't had any chemistry,
an electron is basically a negatively charged particle.
And like a magnet, a negative sticks to a positive.
So we look at something like oxygen.
Oxygen is O2. It's two oxygens sticking together
the force that's driving those two oxygens to stick together
is the magnetic pull of those electrons basically pulling in
getting the two positive charges of the oxygens to
come together around the electrons.
So it functions kind of like a magnet if you will.
So, these charged particles that are
being pushed through here.
So what would happen if I'm pushing charged particles
through here, and all of a sudden...can't go through there.
Obviously, if I'm getting glucose in here
the first two processes are gonna keep happening
all over in the mitochondria.
Remember there's numerous of these.
So there's lots of this going on, and what's gonna happen is
this is going to get built up more and more, and more,
and more, and more, and more - until I have
this massive abundance of extra charge here.
When that happens, there's something that's called
electron leak, which is where we actually get electrons
that are supposed to be being transferred across here,
we actually get them leaking out into this part of the cell.
And those will attach to something like an oxygen
and they'll make something like a hydroxide molecule.
This is what we would call a reactive oxygen species.
Oxidative stress...this is one of the big ways
that happens in terms of like metabolism-based
oxidative stress is when the electron transport chain
can't function efficiently because there's a bottleneck.
We get this built-up of negative charges,
as that charge is built up there's a likelihood that I'm
actually going to lose some of those electrons
free into the environment, if you will, to go
and attach to other things.
So they can take something like a water molecule,
which is H-2-0, and they can break that up into
O- and OH- or something like that
adding negative charges.
When we have an abundance of those
we have to produce antioxidants to then come in
and neutralize those free radicals.
If not, these things can build up.
They can build up into basically like hydrogen peroxide,
like H202, or O2-, like other reactive oxygen species
and what those will do is they will stick to and damage
parts of the cell like parts of the cell membrane
they can actually damage parts of these
components themselves or if the electrons leak into
the inner part of the mitochondria.
They can damage parts of the citric acid cycle,
exacerbating the problem.
We ideally want to avoid the situation where
we'd be getting this electron leaking
so it's important we're not missing any nutrients
for either the citric acid cycle,
for all of these steps to happen easily
or for all of these steps to happen
so there's B vitamins, there's alpha-lipoic acid, there's
coenzyme Q10 is very important for
the electron transport chain - there's a variety
of nutrients that are gonna be important for this stuff
to work in synergy and harmony
when we have had a lot of stress
or when we have had poor nutrition,
or a combination of both.
Some of these parts can get damaged - need to be repaired -
if we don't have the micronutrients to do so,
then we start to get this inefficiency.
Now, at a very low energy demand
if I can still keep up - so like say this process here
is broken, but it can still keep up at low demand
then it's not a big deal.
But what about when we add a high demand of energy?
Exercising per se, we're burning a lot of ATP
meaning that we need to make a lot of ATP
so this means this thing needs to run fast.
The faster this thing runs, the more likely that
any part of this that's just a little bit slower
than the rest is going to start creating some build up.
So when you look at training, at the extreme,
It's kind of like redlining your car
so in your car you have have your RPMs, measures how fast
that engine is turning around.
And there's a section of it where it gets to a certain point
and it's marked red, because once the engine gets revving
that fast there's a potential that
you might break that engine.
Like you're creating so much friction and heat
and whatnot that there's damage possible
or you make total destruction possible.
Same thing for your mitochondria,
when you're revving that thing fully
when you're running this thing, and this thing
as fast as possible, there's a likelihood
that there's going to be some fallout somewhere.
Now this isn't like an engine where you throw a rod and...
(poof noise) it's all done, but you will start to get this
electron leaking, because inevitably
-: even under the greatest nutritional circumstances -
if pushed hard enough, one of these processes is gonna
run a little bit slower than the other
and so eventually if you redline your mitochondria
if you push hard enough, long enough...
we're gonna get oxidative stress.
Now, that may not be a terrible thing
if it's actually your goal of training,
but a lot of people are...if their mitochondria
isn't healthy, they're redline happens way sooner than
somebody that's very healthy.
So in the context of train-ability,
some people - this is extremely trainable
because they have healthy mitochondria
so they can really afford to push that.
For other people, it's not trainable because
a walk in the park actually pushes them into the redline
because their mitochondria are so inefficient
and so unhealthy.
So we have to make sure we're paying homage to
the effect that's stressing this system
has on the rest of the cell.
If I'm leaking oxidative stress, I could be damaging
my ribosomes, so now my protein synthesis is gonna suffer,
I could be damaging my cell membranes,
so now I'm gonna be responding to inflammation a lot more
and maybe I'm not even able to get receptors
in the membranes, so I'm not able to
respond to insulin as well.
A lot of things can start to go downhill
if I'm developing a lot of oxidative stress
and it's inappropriate.
That being said, oxidative stress is an important training
stimulus because if you were drag racing and you took your
four-cylinder Corolla out there and
you're racing a 12-cylinder Ferrari, and you're there
in your little four banger what's gonna happen is
in order to compete, you're gonna be
redlining the whole time.
So you're Corolla... you're gonna be pushing
the pedal through the floor the whole time.
How do you fix that?
Well, you gotta upgrade.
You can't drag race in a Corolla.
That's just stupid.
So what does our body do when it senses oxidative stress?
If it is in an adaptable situation, if it's trainable here,
What it'll actually do - is... you will upgrade your engine.
You will get more cylinders, and by cylinders I mean
we will signal a process to start
duplicating the mitochondria.
So if I train and I get some oxidative stress coming out
one of the things that I can signal from that is
I can signal a process in which this mitochondria,
once all the energy is rebounds
is gonna go through a process where it is going to duplicate
all of the stuff inside, pinch off,
and become two mitochondria.
Essentially upgrading you from a four-cylinder to
if all of them duplicated,
an eight-cylinder so to speak, right?
But you can't duplicate all of your mitochondria
simultaneously because when they're in the process of
duplication they can't be producing energy.
So that's why it's very important that you allow
enough recovery time for you to actually get to
a good energy balance so that some of the mitochondria
can be duplicating while the other ones are able to provide
the amount of energy needed when activity is not very high.
But that's a good thing; then we can upgrade.
So the next time we train, the same exercise,
the same program, the same stimulus would produce
less oxidative stress because each individual mitochondria
would not be being revved as far.
Or you could simply require more.
You could increase performance, and you could
stress those mitochondria some more
and hope for this adaptation again.
Now if you keep doing this over and over and over again
what happens is eventually you get to a point
where you're no longer having that adaptation
but you're continuing to produce the oxidative stress
in which case you'll be getting all the negatives
and none of the positives.
So it's very important that we obey train-ability
and we use that stimulus when it's appropriate
but then we back off when it's not appropriate.
And we'll dig a lot into that when
we talk about the metabolic phase.
But in a nutshell, that's how the
mitochondria is gonna function.
It's gonna take the fuel source.
It's gonna use that to fuel the citric acid cycle,
which is used to fuel the electron transport chain,
which actually does the act of recycling that ATP.
And the important thing to get from this is that
this fuels that in segments, right?
So there's a process here that fuels a specific part
of the electron transport chain and it's then being able
to be in sync and in harmony that keeps
the oxidative stress low.
If you rev it harder, any inefficiencies
are going to stress that system out.
If you rev hard enough, even a good system
will be under a certain amount of stress
so it's always possible to get oxidative stress
if you push hard enough in training.
But it is not a situation you want to be in
if you're creating oxidative stress when
you're not even training hard.
That's a sign that the mitochondria health is very poor.