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Spirometry test

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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looking for deeper water
Jan 26, 2002
hi guys

Thye other day I had to do a medical which involved a spirometry test which ended as a bit of a concern, it said there was a mild obstruction the Doc wasn't impressed and gave me an inhaler thingy for 10days they took a blood test and said I have an allergic asthma to something in the house.

I question is there any concerns I should be aware of whilst diving and using this puffer, is it likely to be detrimental to my freediving in any way :confused:

this is how the test looked, I don't know what most of the letters mean but the one the Doc was worried about was the FEV1/FVC% which apparently is the amount of air you can blow out in 1 second.

height 180cm
weight 70kgs

Measured Predicted %

Best FVC L 6.85 5.56 123
Best- FEV1 L 4.19 4.73 89

FVC L 6.83 5.56 123
FEV1 L 4.19 4.73 89
PEF L/s .19
FEV1/FVC% 55.2 85.1 65
FEF 25-75 L/s 2.69 5.42 50
Omax -25 L/s 4.98 8.84 56
Omax -50 L/s 3.10 5.91 52
Omax -75 L/s 1.09 2.89 38
FET 100% s 6.80

Mild obstruction

As you can see lots of those percentages are only half of what they should be the Doc told me to take this puffer for 10days and go back and I will do another spirometry test to see if it improves.

Should I be worried about this :confused:

Last edited:

Sorry about those numbers being so close together when I typed it they were spread out but for some reason they came together like that.

Anyway the first lot of numbers directly after the letters are what I achieved, the next are what they predicted and the last numbers on the right are the % of the average. :duh

Here is mine (some of it is in german):


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I can't say for sure if your numbers predict an 'issue', but I can say that freedivers (almost always) end up with extremely low scores on some of the more stupid ratios they calculate.

If you walked into the office, and made no attempt at a really deep inhale or a really full exhale, you almost certainly would show up at normal levels. However, it is the very fact that we know how to inhale a bit more and exhale a bit more that gives us screwed up numbers on some of the ratios. For example, the FEV1/FVC says what % of your lung capacity you can exhale in one second. Well, if I do a no-effort inhale and get 6.5L I can exhale 4.5L in the 1st second, which is a pretty hefty fraction. On the other hand, if I make a full inhale of 8L or pack to 10.5L, then the 4.5L exhale in one second now is only barely half or less than my vital capacity, giving the illusion that I have some sort of problem, issue or 'malfunction' in my lungs which is BS. The same idea holds true for the other numbers. If you want to score normally, exhale extremely rapidly with no effort to push out the last bits of air -- just give one powerful exlposive blow. When inhaling, inhale rapidly and make no effort to fill your lungs to the max. Then, you should probably score normal on all the numbers.

Eric Fattah
BC, Canada

Ha Ha I thought that might be the case thanks for your info. I always wonder what they think of me when I walk in Exhale till Im about to throw up then do the most loudest retarted inhale possible and blow into the thing till I go red :D Most people couldn't give a damn about getting a decent FVC ;)

BTW Eric you got any tips on how to get the most out of your fvc on these machines, I gotta do the test again some time this week and would be really happy if I could get an FVC of 7L. Maybe I should do some packing before I go into the doc to strecth the lungs out a bit just need 150ml more air :D


For some reason the spirometry mashine my doctors used with me didn´t work when I pack.
First time I tried it didn´t show anything because I spit a little.
Second one the reading was the same as before.
See my posted reading above? that´s the packed one.
I´ll post the normal one later. It also has the weird numbers in it that eric talked about.

this is it . I hope you can read it... How come the FVC is like ivans
125% but the rest differs so much??


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Mate I can't really read the numbers on the second graph but I can see a 7.54 in there somewhere so is that your FVC. Can you confirm your FVC both with and without packing ??

The answer is yes ivan.
My doctors asked me to do a deep inhale and a maximum exhale. That should be the VC (Vital Capacity) mine is 7.54 liters.
Then I asked them if their mashine could tell a difference when I pack. They did not know even after reading the manual for the darn thing. So we just gave it a try.
At first attempt I spit a little and it didn´t read , the second reading is the graph I posted first. as you can see it also says 7.54 liters even though I packed like crazy!
FVC is Forced Vital Capacity and means something else.
As you see in the first graph of the three I exhale and exhale a little more pushing hard then I inhale. Notice the Inhale goes way below zero liters so I think "forced" doesn´t start at the residual volume but with the diaphragm in a relaxed position.
I found a nice site that tells you about the abbreviations but it is in german not much of help i´m afraid.
Keep looking you´ll find one in english ....


I always thought FVC and VC were the same thing Ie how much air you can blow into the machine after a max inhale :confused:

So which one should be the higher number FVC or VC, ie will my VC be lower than my 6.85 L FVC

Hi all,
First than everything I don't think calling stupid ratios we calculate is the best way to explain the problem.
Those ratios was made for screening and detect diseases (I don't know if you understand sensibility and specifity of a diagnostic test), if the FEV1/FVC ratio was set in 40% we will only detect some cases of obstructive diseases and a lot of cases will be missed, and if it was set in 80% almost everybody will be classified as abnormal.
The results of Ivan and Erasmus can be seen in persons with a Vital Capacity beyond the standards without suffering any disease (for example my brother and I), but this is just a test, if your doctor found something wrong during physical examination like wheezing, then your results show the disease, but if you are completly healthy, this is only a defect of the test, no test is perfect.

I had mine tested a couple of weeks ago and did 3 with packing and 3 without packing.

Average results were:

FVC - 5.8 (no packing)
FVC - 7.3 (with packing)

Just got back

hi guys

Just got back from the Doc after doing some more spirometry.

Before I went today I did quite a bit of Pack stretching and packing practice to see if I could improve my FVC.

I went in there and on the very first go I did a huge exhale inhale then blew It was going great but something stuffed up and it didn't come out with the numbers properly, though on the graph the FVC was up near 8L

next go was noticably smaller in terms of how long and hard I blew for but the reading was 7.16L

and my last go after taking my puffer and waiting a couple of minutes I blew 7.53L which was 35% above average for me, I was extremely pleased with considering that a couple of months ago when I had bronchitis (spelling) I only blew 4.6L :hmm

Frank would you be able to clarify the difference between FVC and VC :cool:

Hi Ivan, good to see you around again.

VC = Vital Capacity
FVC = Forced Vital Capacity

The difference is that in the first you exhale and inhale at your own pace (slow), the VC is the volume you can exhale after a maximal inhalation. The forced maneuver is the same, but you should exhale as fast as you can. Why use the FVC?. In the studies the results of the same individual are more reproductible, with the "slow" maneuver the numbers can change with every test, that´s why the FVC is more used.
Hope it help

Oh right so what is the more effective way to get a bigger number, blowing Slower as in VC or blowing fast as in FVC.

Anyway thanks for your help and im now quite happy with my lungs ;)

I had a spirometer test three days ago, and there was a huge difference between the VC and the FVC values:

EVC (Expiratory Vital Capacity): 7.74l (without packing)
FEVC (Forced Expiratory Vital Capacity): 15.1l (without packing)

These tests were done at a doctor with an electronic spirometer, plugged into a computer. I did one VC test and three FVC tests.

The VC seems a little low but the FVC is way too high.
How can such huge differences occur?

I have a small mechanical pocket spirometer at home to check my lung capacity. Normally the capacity is between 8.5 and 9.5l without packing. The maximum with packing I ever measured on the mechanical spirometer was 12.2l.

Thanks Max for the info you made things a bit clearer for me.

So my 7.53 L FVC is not really comparable to other people when they mention their VC. Maybe my VC is around 3-4L. How can I ask the Doc to measure my VC because the machine he has doesn't come up with VC results.

Also 15.1L without packing is massive I believe Hubert maier only had something like 14.5L with packing !!!!! Would you be able to tell me your height and weight.

I never thought these spirometry tests were so confusing :duh so can you tell me when guys like Herbet who I heard has 7L without packing and 10L with packing I guess those are his VC results not FVC. And Umberto had 7.9L without packing this would also have been a VC result right.

Eric if your reading, earlier you said you had 8L without packing and 10.5L with packing did your machine say these were your VC results or FVC results. :)

thanks guys

My height is 188cm (6'2''), and my weight is 77kg.

As I mentioned in my earlier post, I do not believe the 15.1l FVC value was measured correctly. I don't know how the spirometer machine actually worked. Maybe it wasn't calibrated correctly. Maybe the nurse who set up the test did something wrong.

Why should there be a huge difference between VC and FVC values?
I mean, the only difference in the test is the speed of exhalation. What's measured is still the amount of air you exhale which cannot be strongly increased by exhaling faster.

I know Hubert. He has got a VC of ~10l (without packing). His 14.5l were measured in 1998. He did an hour of painful lung stretching to get this incredible result.

Thanks again Max, will see what Eric or Frank thinks about this difference in your VC and FVC.

So Hubert has a VC of 10L that is extreme and then 14.5L VC with packing is also huge do you know his height and weight ??

I did quite a bit of Lung stretching to get my mere 7.53L FVC I have never done one with packing.

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