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Diaphram and Ribcage flexibility

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Steve Truglia

New Member
Feb 16, 2002
I'm interested in learning different ways to stretch my ribcage and diaphram to assist with deep equalisation. Would some of you deeeeep guys and gals give me some tips please. Also any advice on empty lung training routines. I'm currently doing both these things and would be grateful for some input from those who've had more experience, to learn different methods. I hadn't realised quite how important this flexibility issue was until I took the sled well past the point of my lungs feeling completely empty. I've always hated stretching and am very inflexible at this time. Claude Chapuis attributes his inability to equalise below about 67m to his ribcage stiffness, even though he can stay at depth for ages, so I guess it must be important. Can anyone offer any advice please?:)
I hadn't realised quite how important this flexibility issue was until I took the sled well past the point of my lungs feeling completely empty.

What is this depth (depends, but..)? How similar that feeling is if you compare it to pool & negative dives? At least there's one difference, in pool you really do not have any air, in open water you have, you just feel you don't. That must be psychologically different.
I've never done any CW and I'd also like to prepare well to next summer... I think Frenzel tech will give me ability to equalize (air in my mouth, don't have to take it from lungs), but I want to avoid diaphgram muscle failure etc.

Hi there,
For me it started about 50 metres. That was the first time I felt as if my lungs were very empty. I haven't used the Frenzel yet, partly because I want to try to go as far as possible without it. When I get to a point below which sheer repetition won't help, I'll look to the Frenzel and switch to goggles and noseclip.
Having said that, after a couple of weeks just doing lots of freediving in cw and nl, I found that one day, I just got to 59m and equalised, another day to 62m (the same), then 63m and equalised. Then did a 65, where I felt empty again. I'm led to believe that this is due in part to flexibility and adaption, and partly to relaxing more in the water (not my strongest point!). I did also start some empty lung training at that time which may have helped.
I'm very much a beginner at this so please don't take my views as advice, I'm here to learn and share.
Good luck
Hi Erik,
Many thanks, that's really useful. It's so nice to be somewhere friendly and productive. :)
Off to try it now

Another technique you way want to try whilst getting used to the "crushed" feeling is one that (I believe) Eric Fattah uses for constant.....

When you get to just before residual volume (for you you say 50m). Fill your mouth with air (think of it as a separate unit from your lungs) and close your airway (i.e. don't try and pull any more air up from your lungs)

Then equalize using just the air in your mouth.....I tried this at dolphin, and could go MUCH deeper on empty lung dives than I had done before....

It'll get you deeper definitely, how much i'm not sure, but it's got to be a good thing while you get your ribcage flexible.....and as for stretching your diaphragm.....have you tried the yogic exercises you see people doing (exhale completely and then push your stomach muscles out - can't remember the name now)

Hope this helps...
Thanks Crispin,
I have recently tried this, but find that sometimes it works fine, and other times it takes a bit too long to get the air from in the cheeks, to into the ears. Because of the speed of the sled, this has caused me to sometimes miss an equalisation, and it then seems impossible to make it back up. Stopping and restarting the sled is not an option since I need to learn to do this consistently. (Loic's advice). When I did my first 63 I equalised about 2 seconds after hitting the weights, which would have got me to about 75, had we had the depth. Problem is I probably wouldn't have made that equalisation at that speed, if we had more line under us; that 2 secs would have gotten me behind, and it's not easy to catch up again. On subsequent dives sometimes it worked fine, equalising bang on time. Loic reckons that it's a matter of getting a rythmn going, which needs lots of practice, although he doesn't put air in his mouth; he pushes it up from his lungs with a very flexible ribcage and diaphram. It's probably going to be hit and miss until I get a solid technique in the muscle memory, and a bit of flexibility.
That yoga thing is a good idea, I'll give it a go and speak to my yoga teacher about it too. I think it's an advanced technique, but I'll certainly try it.
Have a good time in Nice.
Ahh, Equalizing

The mouth-fill technique that I invented in 1999 is not easy to master. Currently, only Peter Scott and Herbert Nitsch can do it well (other than myself), and even they can still improve their efficiency.

The mouth fill can be used with various sister techniques, but it really needs the power of the frenzel to get the air in the mouth into the ears.

If done properly, it gives the illusion of full lungs all the way to depth, with maximum possible equalizing speed.

In my case, doing only inverted dives, I would fill my mouth at 30m, close my throat, and then use only the air in my mouth to equalize. It is important to understand that after 30m, I don't equalize 'on demand', I equalize continuously. My tongue applies constant pressure. There is a constant squealing noise as the ears equalize continously. Because of that, I don't even think about equalizing after 30m, once the muscles are doing their job, I can think about relaxing, streamlining, etc.. Even at 88m there was still air left in my mouth to equalize at that depth and further. With a mask I once went to 76.5m and still had air left in my mouth to equalize my mask and ears. As the mouth becomes empty, you must touch your chin to your chest to collapse the dead space in the back of your throat.

Herbert fills his mouth at 45m, which I think is a bit too deep. He would run out of air in his mouth at 75m, and then squeeze the ears after that.

Once the air in the mouth is used up (at 120m+ if done properly), then you can switch to a water equalizing technique, which is too dangerous to describe here.

Above all, I must insist that these techniques can be done by anyone. I strongly dislike it when I hear people complaining that a technique 'doesn't work for them.' It simply means they need more practice.

The mouth-fill is best practiced with a buddy in 15m of water. One mouthful at the surface should get you to 15m when using a mask. Whatever depth you get to, you can then compute your max depth based on your mouth-fill depth. For example, if you can fill your mouth at the surface (1 atm) and make it to 15m (2.5atm) with a mask, then you can reach two and a half times your fill pressure.

Now, filling your mouth at 30m (4atm), you should be able to reach (4atm x 2.5 = 10atm) = 90m, with a mask.

Suppose that you have a very stretchy rib cage and a powerful diaphragm. Then, it is possible with great effort to fill the mouth at 45m. Suppose also that you are using goggles, so you can reach 20m using one fill at the surface. Then, your limit depth is (5.5atm x 3 = 16.5atm) = 155m.

Then, at 155m, you transition to a water equalizing technique, which typically allows you to reach 1.5 times your water-fill pressure, putting you at 16.5atm x 1.5 = 24.75atm = 237.5m.

Experts will argue that you must transition to the water equalizing technique before complete collapse of the mouth/throat, and they are right, but the calculations remain the same.

Eric Fattah
BC, Canada
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Thanks Eric,
I think you've just opened a door of discovery for me.
When I've been filling my mouth with air (as you taught me during our telephone conversation) I'm NOT using the Frenzl. I'm still blowing with Val Salva. The reason is that I didn't get it to work following your procedure. I got as far as control of epiglotis, and soft pallete, but never (yet) got to pop my ears on dry land, using my tongue as a piston. Perhaps I need to keep trying.
Interesting to note that you keep the pressure constantly with your tongue. I may try to keep the pressure constant with val salva, until I get the tongue, piston action sorted. That alone should stop me getting 'behind' and missing an equalisation. If I don't miss an equalisation, 65 is a breeze. I really need to make this consistent, so that I know on a given day how deep I can go with confidence. I'm also deliberately consolidating each step before pushing ahead. This, like all sports I hope, will build solid, repeatable performances and progressive experience and adaption.
I also assume that the goggles will give me another 10 or 15 metres, however, I won't use them on the sled until I can't equalise any further with a mask.
Incidentally, Eric, I have not had a chance to try those goggles out yet. I'm worried about chlorinated water. I'll do it this week and get straight back to you. Your last email indicates I might need to do a little work to get them set up right for myself, I'll know by the start of next week, how it is. I'm pretty confident that I can make them work for me so please email me those details, which we discussed.
I've been doing some empty lung training in a 4m pool. I couldn't get to a point of not being able to equalise, so I forced every last drop of air out and went to the bottom for 30 seconds. I did this 10 times, and wished I hadn't...ouch! What's the best way to do this in 4m. I figured that spending time down would train my bloodshift. Perhaps it was too much too soon. Also, I have the use of a hyperbaric chamber. I know Heimo used one to good effect...any advice on how to determine a dive profile in a pot to train my bloodshift. Heimo did 100 metres for 5 minutes, but I guess he built up to it.
Will start to experiment with the ideas you offered on diet, seems to make a lot of sense.
Thanks for your continuing advice, I'll put a review and link up on my site regarding the goggles, once I've tried them out properly.
Got to sleep now, I've stretched myself to bits today :)
Bye for now,
The mouth-fill is best practiced with a buddy in 15m of water. One mouthful at the surface should get you to 15m when using a mask. Whatever depth you get to, you can then compute your max depth based on your mouth-fill depth. For example, if you can fill your mouth at the surface (1 atm) and make it to 15m (2.5atm) with a mask, then you can reach two and a half times your fill pressure.

To 15m with empty lungs? Or do you have air in your lungs, just closed throat and air-filled mouth?



You can go to 15m with a 'mouthful', with full or empty lungs, as long as you keep your epiglottis closed. With full lungs, you can 'cheat' and equalize the normal way. But, with empty lungs, you must be VERY careful! 15m with empty lungs in an enormous stress on your chest, and you could easily black out as well! So at first, practice with full lungs, or half a lungful.

Eric Fattah
BC, Canada
Yep, that's what I thought, 15m with empties sounds like 'ouch' for me nowadays ;) Thanks for focusing, I'll keep on training.


The mouth-fill is a skill that is challenging at first and can always be improved. So fill your lungs or limit your depth so that you don't get terribly squished but not so full that you can easily draw air out of your lungs to equalize. I usually use a little less than a neutral breath. Get into the habit of doing it on recreational dives to shallower depths on a full lung (no packing) to make it second nature. The constant pressure against a nose clip is THE way to freedive.


I don't really understand why you want to use a mask until it stops you from equalizing. Ear/mask squeeze can sneak up on you during a constant ballast dive--let alone a no limits dive when you're going down much faster. Diving with goggles is much more relaxing and a different experience than with a mask. If that's what you plan to use below 100m then why not train with it at shallower depths to get used to it?
I do support you in your approach to freediving--master skills at each level. Any fool can jump on a sled and take risks. It takes someone who appreciates the sport to learn all he or she can learn. Respect.


So you get to a point where you are effectively "holding your ears open" if you like......

I think I get it now - it makes sense when you say about the constant squealing you get......

I have done this a few times at dolphin, I found it easier to go down with no mask and a noseclip (gives me a heightened awareness of my ears with my eyes closed)

When you concentrate hard you can "pull" the tubes open (thats the best way I can describe it anyway), and you can feel the air going in.....

I can do it more often when spearfishing - don't know why - probably a mindset thing...

When I got it right - sinking from 15 to 30 without having to do anything at all was great, but like I say I only got it right a few times.....makes sense to me now though.....


I have some notes from Umberto's course that i'll copy for you that might help you (there are some good exercises in there to strengthen the muscles that help you push air in using your tongue), and heres the link to Erics home page where you can get his frentzel document www.ericfattah.com (hope thats ok Eric)

Hi, the reason for sticking with the mask, rightly or wrongly, is that if I'm physically able, I'd like to see how deep I can get (meaning 150+), but I stress, if I'm physically (and probably mentally) able. This is such a huge task for someone so new (and not a naturally comfortable person in water), that I'm using the 'train hard, fight easy' approach. The theory, (again it may not be right), is that if I can get to 90 or 100 with a mask, and THEN start using goggles, I'll get a performance boost just at the point where plateau's in progress may become harder to work through. I'm using experience from other sports. After the steep and rapid learning curve that one gets initially, there is a plateau in improvement (that's where most people decide they 'can't' or are 'not a natural' at a sport). By working through it, you progress again (usually at a slower rate), then hit another. As this continues, the progress deminishes, and the plateau's become longer and more frequent. For many sportspeople it wears them down, and it all blurrs into one big stale period. They get depressed, demotivated, and start finding reasons, and making excuses not to train...they self saboutage. The person who succeeds is the person who finds ways through this later period. Most people believe that it's just time, but this only works sometimes. People who succeed with the 'just keep doing it the same way' approach, usually do the right things by default, often without knowing. There are many techniques I use to overcome these challenges (just having been through them before is a great help), and it's different for each person. One of them is to make the training when you are still improving, uncharacteristically hard. This has the effect of making the next plateau much easier to work through. Another way is to constantly seek the advice, and observe those who've already achieved what you want to achieve, or are nearer to it, or have knowledge of it. They will have already found ways around the limiting factors. With that in mind I'm extremely grateful to all of you who are offering advice. In some sports people keep it all to themselves. This sharing attitude is very refreshing, thanks
Sorry for the long winded explaination :) :)
Steve, I think you're quite right about the plateau's that people get to in anything that's challenging. You should see the gym I train at after New Year's day....crammed full for about 3 weeks full of people who, after stuffing themselves silly for a few weeks, make a "resolution" that they will get in shape "this year". Fair enough, and well-intentioned, but most drop out within a month, and many that train a little longer drop out at a low plateau level. I usually stay away from the gym during Januaries ;) . The results seen in intial training are always big: going from nothing to something is a massive rise in ability, and when it of course levels off, they become uninterested and go back to the couch. The smart trainee knows about his/her limitations and copes mentally and physically, using whatever methods necessary to motivate him/herself. Including, I might add, declaring before the world that he intends to become one of the next contenders in an extremely dangerous and challenging sport. The way you are doing things seems right to me, Steve. When I finally quit smoking 10 years ago, I declared to everyone that I had done it, and I did. Maybe I would have done it anyway, maybe not. But it certainly provided some motivation to me when I was tempted in the first few months.
Looking at Stepanek's story is interesting, but he and Paul nearly died simply because they did it "low-budget". Keep going for it, and we know that you will be back the next day to talk about your experiences on the boards, because you are doing it properly. :)
Erik Y. ~~~~~~~~~~~~~~~([:]^)~~~~~~~~~~~

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