# How much lung capacity used..

Just curious if anyone knows what percentage of our lung capacity we use during intense exercise? I heard that lungs are to a point overbuilt and I'm just wondering to what extent, thanks

Of course, lung "capacity" is affected by size, health, previous training,
and diaphragmatic strength. For purposes of simplicity, let's assume
we're talking about a healthy, athletic guy of average size.

A good total lung volume would be about 6 liters. The measurement
that would affect one's ability to "use" the lungs would be what is
called "Maximum Voluntary Ventilation" (MVV). The MVV is the total
volume of air that one can move in one minute. A good number is
around 200 liters/minute. This is a guesstimate, since there are many
factors that can alter this.

From your original question, it seemed as though you are talking about
VOLUMES, and not efficiency. If so, then the MVV is the best indicator
of how much air you can exchange per unit time.

As for the lungs being overbuilt, you compare them with the other
component of metabolic supply, the heart. The heart is capable of
increasing its rate/volume-pumped about 4X the resting amount. The
lungs are capable of
increasing the breathing volume by about 40X, so that may be the
source
of that statement.

The other component of pulmonary efficiency is MVO2 (Maximal
Oxygen Uptake). This measure states how much oxygen your lungs
are capable of extracting from the air you breathe. The "max" number
is taken from extreme exertion trials, and a quick Google search will
provid e a number of tables, etc. that list good #s by age and sex.

Together, MVV and MVO2 tell the story on the performance limits of an
individual. While someone may have a large MVV, they may have an
average MVO2. However, it would be highly unusual for someone to
have a high MVO2 and a poor MVV (You need to get the air in and out
in order to reach the big #s for MVO2).

At rest, you have 4 distinct "volumes" that describe the apportionment
of the lung space:

1. Tidal Volume: this is the average amount of air you breathe in and
out when you are relaxed and not consciously controlling your
breathing.

2. Inspiratory Reserve Volume: This is the additional amount of air,
more than the tidal volume, that you can inhale when you take your
deepest breath.

3. Expiratory Reserve Volume: This is the extra amount you can
exhale, past your normal exhale of the tidal volume, until your lungs
feel empty.

4. Residual Volume: This is the amount of air that stays in your lungs,
keeping them inflated a bit, even when you blow out as much air as
possible.

There. That's a quick primer on pulmonary mechanics and
nomenclature. I hope this helps you to understand the workings of
breathing.

Lee

Thanks alot for the reply man!

"I heard that lungs are to a point overbuilt and I'm just wondering to what extent"

For the average person with healthy lungs, the cardiovascular system will hit it's limit before the respiratory system. However with elite athletes that have a very high cardiac output, ventilation can't keep up with the CV system and so respiration becomes the limiting factor.

92seconds under water for me :)

Koing

The limiting factors have nothing to do with the lungs themselves. The biggest limting factor is the ablity to buffer the the low pH of the blood caused by intense exercise.

Quote:

"The limiting factors have nothing to do with the lungs themselves. The
biggest limting factor is the ablity to buffer the the low pH of the blood
caused by intense exercise."

This is only partially true. If the capacity of the cardiorespiratory
system was greater, then the blood would not build up concentrations
of CO2 or lactate as high as it does. The increased output would keep
the concentrations lower as it "flushes" the system at a greater rate.

There are other factors that contribute to muscular fatigue. If you've
been following the AVACORE threads here, you'll see that this is a more
complex situation than you describe.

But, gee, all I do in my regular job is operate the heart-lung machine
for open-heart surgery. What do I know about hearts and lungs?

Lee

^Pffft!!  Lemme at that damn heart/lung machine.  I mean, really, how f'ing hard can it be?!?!?!?!?!

I can't remember all the way back to Ex. Phys Class but I recall the diagrams with the relative concentrations in gas exchange in the lungs. If I had them I could prove my point.

So, you took one class (which you don't remember) and feel that a few
diagrams can fully explain a tremendously multi-factorial situation
such as this. Although I stated that your response is partially true,
there are more elements in the picture than that explanation would
cover.

It is the responsibility of this forum to provide information that is as
complete AND accurate as possible. If we do a poor job, then
individuals who trust us will not receive quality input. While posting
workouts, etc. is a very personal contribution, posting about solid
scientific information is concrete. Therefore, I'd like to suggest that we
attempt to raise the standard of posting on threads which require
thorough information transfer.

This is not merely a slap at the one guy I've mentioned here, but an
overall request that I feel will take MMA.TV up a notch in
professionalism.

Thanks to all who are so helpful and active here,

Lee

Yes I took one class and they gave me a degree. I'm just trying to engage in a civilized debate and you feel the need to attack my education. So you want to notch up the professionalism cool you should start with your self.

Yes you opperate a heart lung machine that's great. I opperate the actual human body and that's my background.

I don't have any idea of what your education is. All we have to judge
anything by on the internet is the written word, and how well the
communication is conducted. To say you can't remember something,
and then reference things you don't provide, is not professional. I
don't imagine you got that degree by writing your papers in that style.

Besides, this thread is not really a debate. It is asking for factual
information concerning cardiopulmonary physiology.

A degree is the "white-belt" level for beginning your work in a chosen
field. I was at that point 27 years ago. I hope you feel you've learned a
great deal since graduation. I know I have.

pointed out some further elements which affect the situation being
discussed. I feel it would be wise to have sufficient information to offer
if you intend to pose as a subject matter expert.

For 27 years now, my profession has required me to be very well
educated in cardiopulmonary physiology. The principles of gas
exchange, blood buffer systems, and systemic stress are involved in
my work every day. And I do operate on actual humans, with real-time
inline blood gas monitoring that shows the effect of every buffering
action, change in cardiac output, and change in ventilation. I don't
imagine many folks have that opportunity on a daily basis. I'm
provided a huge database of human responses to acidosis-related
processes.

Just have better supporting information before you make incomplete
posts to answer questions on solid scientific matters. I think that's
good advice, not attacking. You obviously wanted to contribute, since
you posted. I respect you for trying to help, but I'd like you to step up

This thread exemplifies one of the major problems with the internet:

the anonymity allows discourse to be held in ways that couldn't happen
person-to-person. I could be a 14 year-old kid posing as LeeA, and
the only way anyone would suspect something was rotten is by reading
what I write. Your post above did not establish you as an educated
professional, judging by the written word. I hope you understand... I
really have nothing personal against you, since I don't know you at all.

I hope that clarifies my position on this.

Lee

" So, you took one class (which you don't remember) and feel that a few diagrams can fully explain a tremendously multi-factorial situation such as this. Although I stated that your response is partially true, there are more elements in the picture than that explanation would cover.
It is the responsibility of this forum to provide information that is as complete AND accurate as possible. If we do a poor job, then individuals who trust us will not receive quality input. While posting workouts, etc. is a very personal contribution, posting about solid scientific information is concrete. Therefore, I'd like to suggest that we attempt to raise the standard of posting on threads which require thorough information transfer.

This is not merely a slap at the one guy I've mentioned here, but an overall request that I feel will take MMA.TV up a notch in professionalism.

Thanks to all who are so helpful and active here,

Lee "

Very well said Lee and the spirit of your threads and the messages you are conveying exactly exemplify how we should communicate on this forum. Kudos!

nuff said.