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My Spirometer results.

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


Freediving Sloth
Sep 8, 2002
My doctor sent me to a casual spirometer test before my trip, since I had asthma when I was younger, and she wanted to know what's my situation.

So, no asthma fear at all, and the proffessor that signed the results said i'm 110% healthy, but I still have some questions.
Ofcourse I looked at Cliff Etzel's thread about this to "translate" some of the findings, but not everything that shown in my test apears in his thread, so here are the results:


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My point is, that I should do better than normal on all accounts, since I'm a freediver - although a novice, but not a Golfer (no offend to glofers out there. Just don't plung any whale's breathhole while practicing).

Anyway, my questions are:
TLC=total lung capacity?
if yes, is 7.25L a good result for someone in my size who never packed?

What's the difference between RV and ERV?

Do I have a residual volume problem? (RV/ERV less than predicted, and PEF 75 shows 94%)
and if I do, how do I train to lower it?

what are:

R tot & SG tot
and what kind of measurement is (kPa*s)?

Many thanks to any opinion or clarification.

Hi DT,
For the way you wrote I note you are disappointed with the results, the same happened to me, I was expecting to have a superb pulmonary capacity. Freediving is much more than two lungs, so don't worry at least you are normal.
For the results you made a plethysmography or a gas dilution method (Helium), but if you have normal lungs the results will be similar
Yes, TLC is total lung capacity and as you see the result is 104% of the predicted value for you
RV= Residual Volume=volume of gas remaining in the lung after a full exhalation
ERV=the maximal volume of gas exhaled from end-expiration
Both values are normal for you and PEF 75 is in normal range too
IC=Inspiratory Capacity=maximal volume of gas that can be inspired from the resting expiratory level
VC IN=Inspired Vital Capacity=maximal volume inhaled from RV to TLC
ITGV=Intrathoracic Gas Volume
R tot=Resistance Total
SG tot=Specific Conductance (the reciprocal of resistance)
kPa=Kilo Pascal a unit of pressure, 1 atm=101.3 kPa
Resistance= Pressure difference/flow rate (kPa/L*s)
With the image inserted you could understand the volumes.
So take it easy with your lungs, you are normal thats the most important to continue freediving
Hope I helped you


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Thank you!

Well, at fist I was supprised in a good way, cause I was expecting for a 5.8L tlc (don't ask me why) and wishing for a 6.8L, and I got 7.25L.

And certainly this test is much better than any of the tests I've done so far (till the age of 20).

I got disappointed when I started to think I could've done a lot better. :) that's the perfectionists' problem.:hmm
But I'm over it now, since those results are with very little training.

About the Helium test, after the normal spirometer test, she (the technician) closed the "chamber" door, and I heard some gas flowing, and I think it's then when she tested resistence, since the spirometer stoped giving/taking air from me at mid breath for a few times. Ofcourse, if I knew it was measuring resistance I would've give it one hell of a fight. :martial

Thanks for the info Frank! You're the man!
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