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increasing lungvolume with packing

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.


Aug 17, 2002
hi everybody

as an addition to all those threads on packing :

i haven´t gotten around doing a spirometric test, yet. but what i´d like to know from those who have : can you give any rough estimation on how much air you are capable of adding by doing for example 10 packs?

i´ve read somewhere in an old thread that one guy measured 18 packs equalling 1.5 liters extra airvolume.

i´m curious.

thanx in advance

extra air

I posted earlier :

Take a bowl or something like that in which you have a scale
(so you can see exactly how much water is in it)
Fill it with water
Suck water out with a straw as much as you can,
as if you were doing a pack
spit out the water and do this again
after 10 packs look how much water is left
the reslut divided by 10 is the amount of extra air you can take with 1 pack
this is not a scientifical result, but it gives you an idea
for me 2lit of extra air, but i stop at 1.25lit for the comfort

good luck
cheers guys

that trick with the bucket and sucking water in sounds quite cool, but i think i´ll wait till i´m by myself (my friends here already start to give me strange looks when they see me sit somewhere and breath and pack).

and thanx also for the link.

so one can be anywhere between 25 to 50 % volume increase with training.

some more questions :

i get to around 28 meters without packing (and a minima mask). are there any suggestions on how many packs might be necessary for 40/45/50 meters??

can you give me also an idea on how long it took you to get to your maximum number of packs??

and finally (so far..) how does heavy packing for max depth affect your weighting?????????

i appreciate your time guys; really glad there are people who share.



Not sure that it means anything to you but, I did some experiments. Things aren't quite what they seem.
I measured:
closed mouth volume..0.13L
70 slow packs into empty lungs..5.5L
10 packs at the pool..0.5L
15 packs in the ocean..0.4L
The easiest way to measure lung volume, proportionately, is by weight change in the water. With proper technique, you probably don't need to pack for 60 meters. I don't have any trouble with 45+, using Eric's method (<5.5L VC, a mask and no packing). Last week, I went to 15 (empty lungs and my mouth full). For me, that is the equivalent of 70 without packing.
hi bill

do i understand you correctly : your vital capacity is 5.5 liters and you get to 45 meters with no packing ??
if so what is ´eric´s method´ that alows you to do that??

about your reference to that empty lung dive : does empty lung mean complete exhale, or do you also do reverse packing after a full exhale (i don´t know how else to describe it)? in which case i´m extremely impressed that you manage to equalise still at 15 meters.

the difference in packs in pool/ocean is something i´ve noticed as well. for me the big difference is dry packing/ocean since whenever i dive in the ocean it´s pretty much pool conditions (somehow i feel like the lucky one indeed ).

the reason for all those questions (i think some explanation is in order) is the following : i basically want to have a rough idea of what depths are achievable. i remember from scuba literature that the average dude is sort of limited to 30 meters. beyond that eqalising becomes impossible (due to compressed lungs) and one can quite easily hurt himself (body fluids in the lungs etc).

i´ve dived 34 m (pb) a few times with packing (8-12 packs) and could rather comfortably equalise. so far i can (dry)pack 15 times, then holding the pressure is just bearable. since i keep training regularly these days and i notice more flexible lungs and better breathing and filling i just wonder where this is all leading me.

i´m a newbie, i scuba dive for 14 years, i freedive since last year. my knowledge needs to improve cause i´m highly interested and i also don´t want to hurt myself.

thanx for the advice


Hi Roland,
I think as Bill.
I have go down 42 without packing, but I do packing in shore before freediving.
The technique Bill told you is to fill your mouth with air 15 meters before the depth you usually can't equalize with valsalva, BTV or any other. It mean if at 45 meters you can't equalize further you should fill your mouth at 30 and continue with the frenzel-fattah technique explained by Fattah before.
I don't believe in limits. You will know how far you can go, I recommend you to find expert instruction on freediving or practice with an expert freediver the first hand advice and security are the best "limit" brokers.
Empty lung is after a full exhale, if you make reverse packs it will simulate deeper depths. I made 12 meters with full exhale. But that takes time, practice in shallower depths before you go deeper. And always make exhale dives with a security diver
Originally posted by fpernett
It mean if at 45 meters you can't equalize further you should fill your mouth at 30 and continue with the frenzel-fattah technique explained by Fattah before

Hi Frank!
Would you please explain what is the frenzel-fattah technique, please. I am trying to digest in few days all the information i learn from you guys.

Thanks in advance, gerard.
hi guys

i understand this technique. but now my question is : when i reach the point where i can´t equalise have i already reached the residual volume?? or does beeing upside down make it impossible to get more air out of the lungs??

my concern is : if i go beyond residual volume what are my chances to hurt myself?? how do i know when or if i get a bloodshift ??

thanks a lot for all your advice


Sorry I missed the questions. It is good to be busy though.
You have the figures correct. I dove yesterday and only could do 12 meters empty. Eric says something like 90% exhale and the rest in your mouth. I fill my mouth with air, exhale fully and 'cough' once. It may be cheating a little, as many people accuse me of having/being a 'big mouth' (American slang for loud and boisterous).
I also made a 'no pack' dive to 41 where I was below Vr. I pulled air out of my lungs OK but couldn't get fully cleared until I turned up. On the dive before that (5 packs and 44 meters CB), I filled my mouth at 30 and easily cleared ears and sinuses fully just before I grabbed the rope. I still had air in my mouth and by past experiments should be able to 5+ meters deeper even if I didn't clear again.

"one can quite easily hurt himself (body fluids in the lungs etc). "

Good observation. Even in the pool it is dangerous. The body needs to 'learn' this fluid lung fill and it also must be warmed up, I think. My buddy recently changed her diving routine. Instead of stepping down, she aims for 3-4 equal deep dives but, the warm up includes two negatives.
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about that nopack-dive to 41 : what do you mean ´i couldn´t get fully cleared until i turned up`?

my main concern is : if i go beyond residual volume what are my chances to hurt myself?? how do i know when or if i get a bloodshift ??
is there a certain sensation that tells me my lungs are ready to go below VR, or do i just notice during the warmup dives that now i´m ready for a deeper one?? do you feel a bloodshift ??

maybe you guys know any links to related articles.

i´ll be back diving in a week or two. and this question of mine needs to be solved and understood completely.

thanx so much.

cheers guys

Hi Roland,
When our sport (or passion) was beginning many people thought that the lung volume will limit the depth, there was a rule that the athmospheres that our body tolerate was TLC/RV (TLC=Total Lung Capacity and RV=Residual Volume).
Bob Croft has a huge TLC and many explained his depths because the TLC/RV relationship was still high, but after him many others like Majorca show that the theory was wrong.
If we take in account just the air in the lungs the depth limit for many of us will be around 40 meters. The blood-shift just change the air content of the thorax with a fluid (blood) making the thorax less compressible. In the Craig chapter of Diving limits of the Book "The Physiology of Breath-hold Diving" he describes experiments with inmersions starting at RV, and the transthoracic pressure weren't as high as it should be, thats how the concept of blood-shift was born.
As you are going down, your lungs will compress but the thoracic cage is more rigid, so it doesn't compress as much as the lungs, that make that intrapleural pressure goes more negative and also the transpulmonary pressure.
With a "negative" thorax and due to the effects of inmersion there is a blood flow redistribution toward the thorax, and the lungs become less compressible thats why the humans can withstand that incredible depths.
As our organism is not static, I think that with training is possible that our pulmonary vessels "learn" to support higher pressures.
My advice:
Don't worry about your RV, it doesn't really matters.
The blood-shift will come, some feel like a sharp pain in the thorax at certain depths, and that will indicate a huge lung compression, but it doesn't mean a blood-shift.
If you are training CW diving you will have the blood-shift, also you can try negative diving to improve your ability before you go to the sea.
Don't hurry to reach extreme depths, do it at your own pace.
When I started serious freediving I felt that chest discomfort at 35 meters, and thought that it was my depth limit, then it moves to 38 and 2 weeks ago I made 40 without any discomfort.
For deeper dives you can warm up with shallow dives in exhalation to make the blood-shift maximal before the deep dive.
Remember this is fun, go next week to the ocean without fears and do what your body tells you, it won't go wrong.
Hope to helped you
cheers frank

very good information indeed. and it gives me some good motivation as well.
can you maybe tell me the name/publisher of that book???

i know what you mean about chest discomfort at a certain depth and after some training you experience the same but deeper.
i also started doing easy negative dives last year and just got a basic idea about the sensation. but i´ll definitely work on that as well.

i´ll be diving in the red sea for about 2 months and then on to se-asia for half a year (diving) so i don´t think i will be in a hurry.

thanx for the encouragement.

what a life

Hola Roland
The book is " The Physiology of Breath-hold diving, Undersea and Hyperbaric Medical Society Workshop"
Edited by Claes E. G. Lundgren and Massimo Ferrigno
It's very good and you will enjoy reading it.
Good luck

Dear all,
During my last health check I used a spirometer to measure the effctiveness of packing for the first time. Immediately my vital capacity was increased by 800ml. It may be a good exercise for lung-stretching and neccessary for reaching the absolute limits, but it should be practiced very carefully, to avoid injuries and pre-dive blackouts (I watched a world-record holder having one this summer!). Personally I am absolutely fond of the frenzel-fattah-technique, because it has really helped me! Whatever is really helping is not hard to advertize. :) This technique is so efficient, that I don't see a need yet to resort to packing for deepdives, even though I only have a "normal" lung capacity (5.5l) and a "normal "cressi super occhio mask. A very reputable freediving-school fell short of passing on to me a proper equalization technique, instead they were vaguely alluding to a diaphragmatic move in a "relaxed" state. Which is fine when You live close to perfect training conditions all Year round. In contrast, Eric Fattah's - method is not only brilliant, but absolutely for free on the internet! Applause!! It allows me to improve on my depth inspite of having only 10 days of practice in a year(!). I am all for proper freediving education but we better make sure we ask people if they have clear concepts for teaching ALL subjects, including equalization, before we sign a check!
To answer the question with the pressure: I believe, empty lung-dives are a good warmup to stimulate the body into a bloodshift-mode without wasting energy for a consecutive maximum-dive. The pressure on the thorax may come shallower or deeper, depending on the shape of the day and should not be ignored. However I had to turn very rarely because of a thoraxic pressure.
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hi gerald

(hopefully i ll mail the next one from dahab)

about your mail: sorry if i m bothering again, but it does seem like i didn t get one vital point after all. so far the equalising technique for deep dives you are using i understood as follows : some where around 30 meters you fill your mouth, close your throat and keep diving down just using the air in your mouth to equalise. is that correct??
i also seem to have a bit of a problem with the frenzel-fattah technique which i so far understood to be equalising using your tongue to push the air into your sinuses.

hopefully a reply will clarify that for good.

i d also like to hear your personal description of how you feel the bloodshift setting in when going below residual volume. or is it just that feeling of pressure, same as when doing empty lung dives??

thanx for the patience and the continuous good advice.


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