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What is "pack stretching" before a dive?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Jan 30, 2001
I was just reading Eric Fattah's account of his deep free dive, and he mentions doing a "Pack Stretch", and "packing 43 times" before a dive. I have been doing a bit of freediving in my spare time for a while, and I was wondering what "packing" is? Is it a spcial technique?

Thanks for your help!!

Hey Sickboy, from what I've seen it's apparently a technique that Kirk Krack teaches in his 500$ clinics. No one's coming forward to describe it, unforunately. Maybe we'll have to fly somewhere and spend the 500 big ones! If you find out, let me know. Erik
Cliff, maybe you could do some digging for this info? Much appreciated, Erik.
I believe it is basically "hyperventalating" or however you spell that.

IF it is hyperventalating, then don't do it. Even though people use that to improve there "breath holding" ability. One thing it does is to mess up your senses so you don't know when you need oxegen and you can black out like nothing, when you feel you don't need any air even.
I don't think it's hyper-ventilating, since most semi-pro freedivers know not to hyperventilate because it makes your body think you have more O2 than it actually does, and so you black out near the surface (Shallow water blackout).

What I think it might be is inhaling deeply, then exhaling completely, but not rapidly which is hyper ventilating. I think it might be to stretch the alvioli of the lungs, to allow the largest volume of air to be breathed in for the dive.
The article says he does this 42 times before going down, whcih seems like quite a lot!!

This is just a guess at what pack stretching is. I hope someone with a bit more knowledge can actually confirm what it is!!

I'm the one who wrote the deep diving stories in which I say that I did pack-stretching and packed 43 times before descending. Pack stretching and packing are very similar. They are a technique in which you can force more air into your lungs, even after you inhale to your maximum. For example, my lung capacity without packing is 7.8L, but with packing it is 10.2L. With a wetsuit on, without packing, it is 7.0L, with a wetsuit on, with packing, it is 10.2L. So I get 3.2L extra air from packing. Almost all competitive freedivers know how to pack. However, be careful, because in the beginning your lung tissue isn't very stretchy and you can damage your lungs if you pack too much. Once you have inhaled to your max, suck air into your mouth as if through a straw. Now close your mouth, and use your cheeks or tongue to push that air into your lungs (not your stomach--don't swallow the air). That is one pack. Pack again and again until your lungs feel full and stretched, but stop there.
Yeah, thanks for clearing that up Eric. I just did a quick try of your pack stretching (in the office!!) and I see how it works.

Do you add the extra mouthfuls of air quite quickly, hence look like a fish breathing? I presume the quicker you do it the less air you waste.

I will definatly try this out next time I can.

Thanks again!

With "practice makes perfect" very true of most things, Freedivers need to practice their skills all the time.

Power Lung is a great tool for all Freedivers...Cliff, our Freediving Editor did a review of the training device here:

I've heard nothing but good things about this tool so it might be worth checking it out.

Stephan Whelan

Deeper Blue [ http://www.deeperblue.net ]
The Online Resource for the Underwater World
Just a quick note to all who are posting that I will be taking a more active role from now on. I came down with a bad repiratory infection on Chrtistmas day and it basically wiped me out til the beginning of March. I will also be getting emails when ever there are postings to the freediving area. Nice to see people like Eric Fattah contributing to the site.

Take care and safe diving.

Cliff Etzel - Freediving Editor

Deeper Blue [ http://deeperblue.net ]
The Online Resource for the Underwater World

There has been quite a bit of water under the bridge since this thread first started and the answers are available to the initial question. I'm wondering what peoples experiences have been with the use of packing. Any comments would be welcome.


Eric Fattah - please email me privately

Eric - would you contact me privately at my email address. I want to ask you some specific questions regarding deeper diving...

Under the bridge(way under)

Hi all, since Eric Fattah's post, I have experimented with packing a lot. I have found that it definitely helps with equalizing at depth, and think that I have reasonably good potential for some deeper stuff since I have had some practice with it in the last month.
I haven't found that it has helped my static breath-holds. It takes a fair bit of effort to do the packing, and a fair bit of effort to hold the air in, especially between 20 and 50 packs. Enough effort that it has so far eliminated any extra time in my static attempts. My best "on the floor" static is 6:05, and with 20 packs, 5:30. I do know that the big record holders use it for static though, so I think I need more practice with it; maybe more often.
I will be going to the West Coast of Canada this month to join a good friend who you all know;) , and will see what kind of depths I can reach with this technique.
Cheers, Erik

Since I asked the question, I guess I should also share my experiences. I have a horrible time packing with a snorkel in my mouth, so I don't do very many in the water, but I have started to routinely pack-stretch during my pre-dive warm-up. I'll do a basic Yoga/Tai chi exercise for about 20 minutes and then do pack stretches, by taking a big full breath, raising my hands above my head, and then packing, once I'm packed I side stretch holding the packs. I start out 10 packs to both sides, then 20, and finish right now with 30. My sense is that this really has helped my overall volume and my working volume once in the water. Most performance freedivers do not use a snorkel for many reasons, packing being only one of them.

Best wishes,

When its time to start packing

The discussion about packing is interesting. I think it is important to realize that is but one of many techinques and everyone has to find the approach that works best for them. Hell, we used to lay down and have people stand on our chests and/or stomaches and then try and push them as high as we could without lifting our backs of the floor as many times as we could. I have no idea if this helped in anyway but we thought we were cool. At that time we didn't now anyone who trained to hold their breath and go deep. Most people never pack and some are major competitors. And packing is not without its risks, including blackouts, rupturing blood vessels, siezures, and cardiac arrest to name just a few. I get concerned when I hear about people doing 40+ packs without discussing how long it took them to work up to that capacity. Initially I seldom did more than 3 packs because I got uncomfortable, but now I am up to about10 before I start feeling discomfort. It does require energy and is very difficult with a snorkel. I only pack when I am going for duration as I find that I tire much more quickly when I pack frequently. It is a trade-off between the length and depth of the dives or the number of the dives. Unless I am going for over 180 seconds I don't pack. The other aspect of packing, one that I think is under recognized, is its value as a part of dry training. Not only is valuable for increasing oxygen tolerance but also for increasing our psychological and physical accomodation to more gas volume than is typical. When a person first starts increasing the volume of air that they are holding static their heart rate increases in response to the pressure and oxygen build up. This is an autonomic response and only with repeated "pumps" does your autonomic system not respond to these increases. As you dry train with you will increase your holding capacity for breathing up without packing. Part of the trick with packing is to learn the balance between forcing air in and muscular tension. Initially found that I was trying to use my neck, shoulder, chest, arms and stomach muscles. It took real concentration to learn to relax while packing and only use face and throat muscles. I think this is more important than the number of packs. Read the article on epiglotal training for this. And then there is reverse packing - Hey Octo, how about a little advice on reverse packing? I also have a power lung as well and have seen improvements within a week or so. Still learning after all these years, Angus
Snorkel packing

It's good to have a person like Angus who's knowledgeable about our physiology. Incidentally, when I'm diving, I breathe up for my 3 minutes, gently turn over onto my back for a full exhale while taking my snorkel out, pack,equalize, and then dive, in that order. I've never tried to pack with a snorkel in my mouth, I don't think I could do it. I'm off to the local mudhole to look for -30 metres, Cheers, Erik
Heal thyself

Erik, thanks for the acknowledgement. :hmm Now if I could only use my knowledge to get my weight backdown .... Angus, the potbellied waterbull.
LOL! - I love that last line Angus!

Actually - I have been in some pretty intense training the last 2-3 months - I have lost 20 pounds and dropped 2 pants sizes in the process.

In february, I weighed in at a hefty 230lbs, thanks to being deskbound for so long.

Realized I was a poor example and got on the ball - I lift at least once a day and swim 1/2 mile, or fin swim a mile - every day!

Cut my caloric intake to about 1500 - 2000 calories during this time as well. Virtually no pasta, only orgainically grown meats (beef and poultry), vege's and fruit with suppliments. Has made a HUGE difference in my energy level for training.

Am now beginning the harder process of using the Powerlung twice a day and doing some dynamic apnea training in the pool.

Sure you still wanna go diving? :D

I want to get some freediving photo's done - Never been to Waldo Lake - is it any good? How warm is it? Clarity?

Lets do this soon - What about the last weekend in July?

Dear Cliff, Thanks for the psychological boost. I have been so desk bound that I forget I could actually get up. I'm 6'2" and now about 220 with a :eek: 38" waist. I have recently switched to a similar diet and have just started training again. Over the next year I plan to get back to diving trim which means about 190 with a 34' waist. I way past the need for cosmetics, I just thought it would help my diving if I could get into my wetsuit without feeling like I just swam a 50 s 100 meter freestyle (and that is just a fading memory now).

Waldo lake is considered to one of the clearest bodies of water in Oregon and that includes Crater Lake one of the clearest in the world so it is right up there. Visibility is usually 100+ feet. It is about 178 feet deep and big. There are fish but it is pretty sterile. Mosquitos can be a real problem so being in the water is best. I have only dived there once, back in my well spent youth, meaning poor adventuring, without a wetsuit so I was not in for very long but have always wanted to go back. I just don't remember why.

I would love to go diving. Late July might work, just depends on how well the packing for our move is going. Utah isn't sounding so bad for diving after all and we only be there for one year. There is place called the Bonneville SeaBase which is a series large hot saltwater "ponds" that have big tropical fish in them, including nurse sharks up to 6'. Then there is homestead crate which as 95 degree hotspring that is 65' deep year round. You'll have to come visit. Did you get my private message? Let's work something out, Angus

Oh, Octo and I will be very photogenic too. Okay not Tanya or Umberto photogenic but I do a really good imititation of a walrus or a really big seaotter. Octo just looks like a water elf - going bad. So there will lots of photo ops. I have really skinny legs and maybe I can get the proportions of a dolphin and increase my laminar flow. Or I could just get my medications adjusted . :t Angus
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