Lung capacities and volumes?

[Newbie_spearo]

Hey All,
I remember reading a thread about this a while ago but can't seem to find it again. I had the chance to get my lung volume or something along those lines tested at uni today. I know that there is some confusion as to what is what exactly but I was wondering if anyone could give me some insite as to what this all means. My FVC which is Forced Inspiration volume is 7.436, 128.2% of the predicted norm for someone my age weight and height, my Forced Expiration Volume was 5.786, 120.3% of the norm. I believe the above figure are in Litres? The ration between the 2 which should be 100% was 93.2% but that is most likely due to me being an asthmatic. Can anyone tell me exactly what this means and if anyone themselves has had the test please share your results.

Jono

[azapa]

I am pretty new to this too. there is great info on the web and in freediving books like Umberto Pelizzari's. Your Vital Capacity is what you can actually exhale. Your tidal volume is what you inhale and exhale in a relaxed state. Your residual volume is the air in your lugs that will remain after a forced exhale. It seems that most freedivers refer to their Vital Capacites (VC) as it shows what they can Inhale naturally, or using packing. The later of the two will of course be up to 25% more. I weigh 64Kg, am 179cm and had 6.7l VC in Nov. last year. I have been diving a lot so expect 7l now. I don't pack.

[perow1]

Forced inspiratory volume corresponds to the volume you can inhale forcefully during the first second of inhalation. This does not neccesarily correspond to the vital capacity.

A value of 7.4lit seems to be a whole lot, since most people cannot fill their lungs completely whitin a second. Are you sure you did not confuse FIV with IV or VC (Inspiratory volume och vital capacity)?

Forced expiratory volume is the amount of air you can forcefully exhale dureing the first second of expiration. This FEV is often expressed in percent. FEV/FVC This gives you a value comparable between individuals of different Vital capacities. A 30 year old male should have a FEV% around at least 80%

The percentage you were given are compared to average values of a person your age and height.

I suspect that you made a measure of your vital capacity and not a forced inspiratory (during one second) measurement and that you also did a FEV test. In that case your FEV% is around 77% which might be about 90% of average. (the numbers do not add up otherwise)

[Newbie_spearo]

here is a copy of the computer print out with all the relevant values and percentages.

[perow1]

Yes, this confirms what i wrote earlier. Your vital capacity is around 7,4. Your FEV is 5,786 which gives you the FVC/FEV ratio of 0.77 which is around 93% of the predicted value.

The 128% and 120% of predicted value is compared to someone your age and height. The ratio FVC/FEV is calculated using the volumes and you are predicted to have a ratio of 0.833 (or 83% of your total VC blown out during the first second) You do however get around 0.77 (93% of the predicted value) which may be due to your asthma.