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lung volume measured, +3 litres with packing

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Oz freediver
Oct 3, 2001
Hi All,
My friend and I got our lung volumes tested, with and without packing. There is a Physiologist that is doing some research on freedivers and wanted to measure subjects with packing. We had to step into something that looked like a time capsule and then blow into a hosey thing. That's my technical description of what's called a Plethysmography. :D
We were told it's the most acurate way to measure lung volume, much better then a spirometer. It was a sealed box and also measured pressure changes. We also had to inhale some type of gas so it could actually measure RV as well, rather then just estimate.

My readings, normal:-
VC = 6.7L and TLC = 8.4

with max packing it was
VC = 9.6L and TLC = 11.4

So that's about 3 litres extra with packing. Does anyone know what the limits for packing are ?
I may be able to build up a little more but not much I think. I know in my case I get dizzy when I pack to the max and then exhale. Luckilly I don't suffer from packing blackouts when breatholding. I know both Lotta and Herbert pack a lot and had quite a few packing blackouts in training in Cyprus. Perhaps the limits partly depend on the strain on your heart and how much you can pack and still stay conscious ?

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Wow, I just started packing a few months ago.
I'm really impressed by the 43% you gained, you still have a
normal full set of lungs @ like 20 feet! I think my gains are
closer to 5-8%.
Have you tested your surface static times with and without packing? It would be interesting to see if the extra air volume%
matched the static time%.
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Hi ramstam,
packing definitely increases my static time, but certainly no where near as much compared to %extra air volume.
Whilst training in Cyprus I did increase my static PB going from about 6.25 up to 7.02. Mostly due to extra packing. In the past I used to pack only a little because I wouldn't be very comfortable with a lot of packing. When I pack a lot on a static there is a lot of pressure on my throat, sometimes it's hard to hold the air back.

My guess in my case that packing adds about 40-60 seconds to my static.

Some factors why packing may not add as much as you'd think :-.
It takes time to pack, in my case at least 20 seconds to get close to max. That's 20 seconds you are already effectively holding your breath. Packing takes a bit of effort. It definitely raises the heartrate, although stroke volume reduces I think you still burn O2 a bit faster then normal. That may also be partly due to it being harder to relax.

I think packing definitely helps big time with depth diving. At the very least it gives you more depth before you run out of air to equalise with.

I also gain about 3L according to my spirometers:
No Packing FVC = 7.80 - 8.05L
With Packing FVC = 10.50 - 10.93L

All my pb's in static have come with excessive, uncomfortable packing. I struggle to hold the air in for the first 5 minutes. Only after 5 minutes can I keep the air in my lungs without effort. It often slowly leaks through my throat into my mouth, and I must push it back in repeatedly.

Eric Fattah
BC, Canada
My limit for packing is the actual pressure in the lungs that makes me feel like the diaphragm is stressed to its limit (usually only when stretching dry), or that I simply can not hold the air with my throat (epiglottis?).

Packing blackouts become more likely, the more I pack, but it even occurs when doing a few packs only. This tells me that it mainly depends on the state of my cardiovascular system, how sensible my body is to packing BO. Unfortunately I have not found out how to manipulate my cardiovascular system effectively.

My packing volume was 4.3L (2 years ago), by now I think that I am close to 5L :duh

I just want to point out that one can damage the lungs seriously when over-packing :naughty
Herbert I watched you packing when you were doing static training in Cyprus - I was absolutely amazed at just how much you managed to pack! Particularly when you had a little sleep :)

I'm very new to this sport and Cyprus for me was inspirational - its really made me want to learn and improve my performance - I know I've got a lot more in me...

At the moment I don't pack at all, mainly because I don't think with the CW depths and static times I achieve, I need to - but how do you a) train to pack safely and b) know when packing will benefit your peformance?

I know I've gone off the thread slightly but any help/advice would be appreciated...

Donna :)

Ive got a question for Wal, Eric, and Herbet. Roughly how many packs does it take you guys to add the amount you are getting. Herbet 5L extra is outta control, what does that bring your lung volume up to.

Originally posted by efattah
Only after 5 minutes can I keep the air in my lungs without effort.

What happens at 5 minutes? Do you let some air out? Or does it take that long to adjust to the pressure?

I find my throat really hurts during a static, sometimes badly enough to abandon the whole thing about 1-2 minutes into the static. Packing makes it too painful to bother with.

I was born with a cleft palate, which I think is the reason why I can't equalise hands free (hole in the hard palate joins my sinuses), but could that also affect my ability to hold air in my lungs after packing? I couldn't swallow properly until I had surgery 6 months after I was born.
Wow 5 ?
Sounds like I still have a couple of litres to go. ;)
Hey Ivan, it takes me about 30-35 packs. You start of getting a a lot with each pack then towards the end get very little as the pressure gets really high. I'm not an expert on packing I can't get it to work like most people. I have to hold my nose or it doesn't work. Also use my cheeks a lot more and it makes a lot of noise. Herbert was giving me funny looks when I did it in Cyprus :D

Very interesting discussion here. This should be way to improve my static PB. I never did full packing before static, I was told it is contraproductive.

I found out strong packing can prolong my dives efficiently. Recently I improved my dive-lenght up to 3:06min with deepest point 11,6m (bottom). This wasn't a deep static, because I did som 50 or 70m swimming down there.
Eric F,

You mentioned that all your personal bests in static were done with packing. In terms of percentage of time, how much more hold time does that buy you ?

Also, you mentioned you fight to keep that packed air in. How much more difficult or uncomfortable is a packed static vs a non-packed static ?

thanks in advance !
I'm stoked on this thread too. I had the understanding that
packing was used to give extra air to offset the volume loss
at depth, allowing for deeper equalizations. Now I think I have the tool I need to break over 6 min on my static times.

You weren't asking me, but give a packed static a try and you
will feel I tight feeling in your throat. Feels like a really bad
version of the lump when you are sad.

Thanks Wal, I also get less and less air towards the end and then If I push it real hard it starts making weird noises :D

After reading this thread I had a go last night at beating my pb for packing which I did by 4 packs, so I guess I should start practicing packing a bit more.

I don't usually pack for statics, as I don't find it gives me any extra time, but maybe it's worth trying again! As I explained in another thread (Lung volume during statics), if I pack a lot there is a feeling of pressure at first, but then the volume of air seems to decrease, or maybe something stretches, so it becomes easier. This can be so much that if I pack to the max and do a 4 to 5min static, the first thing I do afterwards is breathe in, so there must be quite a lot of extra space.

For me, the limit of packing is when I can't get any more air down! I have been careful not to overdo it.

At first I could hardly take any packing without almost blacking out, but now this is not a problem, and I feel perfectly fine doing it.

My VC is 4.4L, and 5L with packing, so I must be packing 0.6L.

I don't know if these measurements are completely accurate, as they were done using a measuring jug, a sink full of water and a shower hose!!!

More info on my statics:
- As you hold your breath, three things contribute to the air shrinking:
1. Usually RQ < 1.0, so every molecule of O2 consumed produces less than one molecule of CO2 (excess being converted into water)
2. As O2 is converted into CO2, the CO2 dissolves into the body water and plasma, and thus doesn't only exist in the lungs (this is the biggest effect)
3. The rib cage & diaphragm gradually stretch during the static as well

That is why during my statics, I start off with a hugely uncomfortable amount of air, and my neck is extremely tense for the first 4-5 minutes. In fact, just to hold the air in is extremely unrelaxing. As the air gradually shrinks, finally at 5 minutes I can fit it into my lungs without having to bloat my cheeks. Usually I keep my cheeks full of air in the first 5 minutes to offload the pressure from my lungs. If I can squeeze all the air into my lungs at 3 minutes, then I know I didn't pack enough or I wasn't stretched enough. The more I am stretched, the less I stretch during the static. If I am fully stretched, there should be no progressive stretching which happens during the static, only air shrinkage.

Even though I'm extremely tense trying to hold the air in, I still gain dramatically, 8'20" w/packing vs. 6'30" without.

For me, the worst part of the static is the first 4 minutes. The struggle phase (contractions) at the end are much more relaxing than the early part of the static, because the air fits into my lungs very comfortably and I can relax at a lot more.

Eric Fattah
BC, Canada
Eric, thanks for the explanation, I was wondering what was happening!

For me, the best part of a static is the first 3:30 - 4min, before the struggle phase starts, though it seems to be starting later now, and I am getting used to it.

I'm not much of a packer (Sven's gonna have a field day w/ that one), but I have noticed that I lose buoyancey over time when I'm underwater (this is over the course of a single breath-hold).

Not sure if it is due to gasses being absorbed into tissues (C02 is more than O2) or due to conversion of some O2 into H20 (i.e. RQ < 1).

At any rate, it implies a reduction in displacement over time and I suppose it corresponds to a reduction in the volume of air in the lungs. I wonder it is a factor in the reduction in effort of holding in packed air over time?

oops, posted this before I noticed Eric's similar, but far more complete explanation above. I feel kind of clever for thinking of some of the same ideas:cool:, but stupid for missing the post:duh
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I once did a static with lots of weight (at the surface of a pool). By the 3'30" mark I had sank to the bottom!

Eric Fattah
BC, Canada
When i pack and do statics i feel as most of you guys mentioned high pressure against the throat, i stuggle to keep the air in the lungs(dry statics i often hold my nose to prevent air leaking out).

But after statics i get a really weird dark voice, like if I had a bad cold or something. Any other of you guys experience the same or know if the vocal cords can take any damage from the packing. :confused:

Very intresting thread! :)
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