Failure depth

[Alun]

I'm not a big fan of 'half-lung dives'. the problem with them is that it's difficult to judge how exactly much air you've inhaled. you could have inhaled only 40% of your VC when you meant to inhale about 60%. ie. you've stored less O2 that you think. It can be easy to overstep the boundary, especially if you are trying to dive deep.

empty lung dives will feel weird if you're not used to them. 7m on an empty lung is fair amount - more than enough for a first attempt I'd say. try diving after a passive exhalation to begin with (very nearly empty), and don't dive as deep as you can. Begin with about 3-4m. In the beginning, just do one or two gentle dives, then gradually build up the depth over weeks and months. the important thing is to not to push beyond what feels comfortable.

"exercise the ear drum"... i dont understand this idea. I don't see any benefit in stretching the ear drum, if that's what you mean. i do empty lung dives to condition my lungs for deep diving, not as an exercise for my ears. If you use the mouthfill method, then equalisation is no harder than at any other time. Your ability to equalise depends on how much air you have in your mouth - nothing else.

 

[samdive]

thanks Alun, it wasn't the first time I'd tried empty, we used it a lot out in Egypt but it seemed to be frowned upon over here so I hadnt done it for a while..
ex

the idea behind exercising the eardrum.. well when you have had a perforation the eardrum loses quite a bit of its elasticity because of the scar tissue and rather than your ears clearing smoothly and gradually they tend to clear more by a series of cracks and bangs which is kind of noisy and off putting.... I asked Lee if he could think of any "yoga for ears" to get them supple again and he suggested empty lung dives.. it did work a bit so was worth a try...

sam

 

[Alun]

frowned upon? oh? I dont really see why.

oh, i see what you mean about exercising the ear drum now. I really don't know whether stretching the ear drum will help it regain its elasticity. it might help, then again it may even weaken it? i really dont know. you could talk to an ENT doctor about that, and the risks of another rupture etc.

i think the best solution is to work on your equalisation technique. it's possible to dive to (effectively) any depth without feeling any pressure or hearing any pops at all... if you use the right technique, which needs practice. this can be done using the frenzel combined with the mouthfill. i learned this when sled diving with SteveT earlier this year.

the idea is that you fill your mouth with air and lock it in with the glottis. then you apply continuous gentle pressure with your cheeks and tongue. this action keeps the eustachian tubes open and so the increasing hydrostatic pressure is continuously equalised. so you dont follow the usual pattern of:
ear drum bends in
equalise
ear drum bends in
equalise
etc

this is not the ideal approach in my view, because it does put strain on your ear drum. over months and years it probably doesnt do much good, and it could well contribute to things like tinitus. Don't know that for sure, but i wouldnt be suprised.

so with the continuous Frenzel equalisation approach, your ear drum doesnt bend at all - no stress - no need for increased ear drum flexibility - no risk of rupture.

usually this is done from about 30m downwards. normal Frenzel from surface to 30m, but you can do it all the way from the surface. you'll just need to top up the mouthfill once on your way down to 30m - that probably suits sled diving better. it was awesome to do a 50-60sec sled descent without feeling any pressure on my ears and no popping sounds! the other benefit is that you dont have to 'monitor' the pressure build up and judge when to equalise. the process is continuous and automatic in a sense, so you can mentally switch off more.

alun

 

[Ben Gowland]

Eeek - frowned upon!

Time for some

Sam - if you want to exercise your eardrum - I would recommend that you first let it heal properly and then equalise and deequalise on land. There's no need to do it in the water.

I have eardrums of steel :t from popping away at my desk and from playing loads of underwater hockey - down to depths of 5m, so am constantly training my ears to equalise.

Interestingly,when I jump in the water I have to equalise as soon as I get past 3m, but after half an hour of popping up and down I don't 'need' to do it until past 5m. Although I do it anyway for safety's sake.

You should always equalise your ears as often as possibe - if you can't do it continously as Alun says.

I can't understand why someone would recommend empty lung diving to 'massage' your ears

Empty lung diving is about learning to equalise with empty lungs, to learn to stretch your diaphragm and to train your lung tissue to accept blood shift more easily.

right, time for me to :mute

 

[Erik]

Re: Eeek - frowned upon!

Originally posted by Ben Gowland
I can't understand why someone would recommend empty lung diving to 'massage' your ears

....probably good intent, but misguided and uninformed. Being a reasonably good diver doesn't necessarily mean being a good instructor or advisor. That was among the worst advice I've heard....scares the hell out of me! Negative dives collapse the airspaces so fast that this is not a good technique to try and stretch the eardrums. As Ben says, do it sitting in front of the computer....and really this is more about keeping your eustachian tubes open. And who needs to stretch their eardrums anyway, if the proper technique is used? Maybe Eric F and Herbert N and Carlos C, diving past 80 metres, but not the rest of us.
Sam, if you value your eardrums ( I know you do after reading your website) then take care of them, or you may not be diving much. Listen to doctors (Dr. Gowland perhaps) and take anything you hear or read on the net with a grain of salt. I have had more bad advice given to me than good, and I have also had bad advice from good instructors and good doctors too, so I really try to analyse the advice I get now.
Ok, time for me to :mute too!
ps Sam, have you been up to Dahab and the Blue Hole?

 

[samdive]

dont worry guys I have seen about half the dive ear docs on the planet and they all think it looks fine

thanks for the advice but resting it and practising in front of the computer wasnt an option this time as I burst it 2 days before flying to hawaii.....

maybe I should build an ears website....

sam

 

[Ben Gowland]

Don't trust those quacks!

Nice Avatar Sam, by the way.

 

[samdive]

and no I havent been to dahab.. full of smelly hippies isn't it???

only kidding but not my kind of place..

sam
x

 

[Skindiver]

negative dives and ears

Hi Sammy

Before Hawaii i did an hour of messing about in a 5m pool with my team mates doing negative dives. ( first time )
Getting to the bottom seemed easy enough and the big thing between us was to produce a mouthfull of air at 5m and then to equalise with it again.

I had no pain and it all seemed to go ok. The next day my left ear was blocked. If i pushed on my ear from the back towards the front i could unblock it for a bit. Releasing it though would block it gain. If i pulled a funny face and really pulled the inner muscles controlling 'God knows what' including the bit that crackles your eustachean tube, i could sometimes unblock it for a second. i would keep trying in the hope that that time it would pop open and stay open.
I stuck an earbud in up to my elbow and ... nothing except much creaking popping and crackling noises. If i equalised it gave off a noise like bubbling. No pain though. Just a full swollen feeling.

This seemed to clear with some drops and at Hawaii things were fine till the static comp. During my breathe - up on my back some water seemed to get into my ear and it blocked intermittantly till i got home after the flight and then it blocked solid again for days. Same symptoms.

It cleared up after a bit and the first time i went to hockey it blocked again without me getting water in it. ? Its almost as if it is sensitised to water / chlorine water and swells and blocks at the sight of a pool now.

Doc looked and said the ear was clear but the ear drum was bulging outward, seeping some liquid and was scarred.

Prescribed drops. open again and feels fine exept I have not been in much again since, i'm too chicken incase it blocks again.

Skin.

 

[samdive]

THANKS

Hey Skindiver! you made me smile! I am not all alone in the weird ears world... your symptoms match mine exactly which I guess is why I posted on here in the first place.
Don't know what we both did but at least someone else has had the same.
Doc Pro Plugs looked at my ear in hawaii and gave me some of his plugs so gonna try those next time I get in the sea.

my ears still a bit crackly but does clear even on yawning so I don't mind that too much, let me know if you find out more

sam

 

[loopy]

Slightly off topic, but maybe not... I've got a few questions on barotrauma's if y'all don't mind.

First up, if you have a mild barotrauma, how long should it last? Is there any possible medication for it, like drops? And finally, has anyone heard of any recorded instances where someone has packed their lungs, opened their throat but left their mouth closed/nose blocked, and recieved a barotrauma because of this?

Thanks for your help!

 

[Ben Gowland]

Nope - but it is theoretically possible.



All the stuff in that article by Erik Seedhouse is somewhat questionable from a physiological perspective. I don't know how many freedivers Erik has come across to have these effects. The 80 mmHg is an interesting figure - a forceful exhalation should have the same effect as a fast ascent from depth - hence we should be at risk of embolism whilst heavy breathing - and would most certainly be getting embolisms whislt packing.

Has anyone EVER heard of a freediver getting an embolism or pneumothorax? I accept that in many instances if it did happen, it would be unlikely to be diagnosed.

Ben

 

[Alun]

Ben: you probably meant to say
"a forceful inhalation should have the same effect as a fast ascent from depth "
instead of
"a forceful exhalation should have the same effect as a fast ascent from depth " - right?

In fact, by inhaling from RV to VC very quickly, you can simulate an ascent from 35m to 0m in about a second - no big deal and certainly no risk of lung damage. I think this is what you were saying, right Ben?

However, when diving with a nose-clip and packed lungs I *always* make sure that I exhale a small amount of air about 1m below the surface. imagine that you can achieve 110%VC with packing, that means you will have 100%VC at 1m. The idea being that exhaling perhaps only about 20% of your air at about 1m will stop your lungs from expanding from 100%VC to 110%VC in a fraction of a second. The lungs may well be able to cope with such a sudden expansion at the limit of their elasticity, but then again, they may not. Of course normal packing takes 10-20secs which gives time for the lungs to expand. The ascent from 1m to the surface simulates the act of packing in about 0.5sec - this is the possible danger. I think it's a sensible precaution to take, and it has no significant effect on your ability to maintain consciousness, from what I can tell. I have to stress that I'm talking about a very small exhalation - just below the surface - certainly not below 2m. You have to time it quite carefully.

When packing with a mask, this is unlikely to be necessary. Excess air will simply vent from the mask - you'll not be able to reinhale to 110%VC, and so there should be no risk to the lungs.
(Incidentally, one other factor in this is that your lung volume should be slightly lower after a dive, with all other things being equal, due to the burning up of oxygen. I'm not sure what the figures are. But i do know it's so small that it can't negate the effect of maximal packing over the course of a normal dive.)


alun

 

[samdive]

Has anyone EVER heard of a freediver getting an embolism or pneumothorax?

did they ever find out what happened to Benjamin Franz? that sounded a bit like it could have been an air embolism?

 

[Ben Gowland]

Am I wrong?

I did mean exhale. I realise that the lung volume change is the equivalent of an inhale, but the lung pressure issue is equivalent to an forceful exhalation - thus making pressure inside the lungs slightly greater than external (irrelevant of volume), this is the concern (or not!).

Lung volume in the last few meteres of dive:

assuming the 110% rule a short dive to 5 m and back would be as Alun says, but also as Alun says there will be a volume reduction if the dive is a long 'un. I think the figures are around 15%. If you absorb say 80% if available O2, and say 10% of nitrogen (probably too much), and pump out 4% lung volume of CO2 (probably more than real). That works out as 90% (110+4-8-16). Which sounds as though it is of little concern...

BUT!!!!

What about blood shift? That will fill up a percentage of the lungs and will remain there at the surface. It will probably be around 10 - 20% (dependent on depth dived) so we could be back into bad territory. That blood would be forced out of the rib cage on ascent - which woul up the pressure in the brain (good) transiently, and would then be followed by a reduction of pressure in the brain (below norm - bad).

So the lesson is....do as Alun says! Breathe out a bit in the last metre or two - I always do - out of habit rather than out of reasoning.

(Alun - check it out with the model - I will send you lateste update - may have a pop at this paradigm too).

 

[loopy]

Hey doc, cheers for the replies guys.

Will blowing off air below the surface put you more at risk of SWB/samba?

The reason I asked about barotrauma's before (and I should've explained, I meant just inner ear bt's) was because I think I may have done that to myself over the last week or so. On Sat, I did a lot of work practising my equalising in a 5m pool, because I've always had problems doing it inverted. When I woke up on Sun morning, I could fel like a slight pressure inside my ear, like I was equalising and holding it. This was in my right ear, lasted about 3 days or so, then went away. On the last day, I was practising packing for pretty much the first time, and to do it I need to hold my nose, to stop air getting out there. At one stage I had my nose held, and my mouth closed to try to force the air down, but when I opened my throat, I accidently let all the air rush out. I didn't think it'd be too good for my right ear, but it didn't seem to effect it, however about 3 hours later, my left ear stated doing the same thing as my right. It's been slowly getting better too, and should be ok by tomorrow or so. I've kept myself dry to let it heal properly before going back in the water. That's also why I asked if there's any kinda medication or anything like ear drops - not that I need it, but maybe for next time.

Cheers again,

Brad

 

[hydro]

holding nose when packing

It sounds you are doing something wrong when packing. You don't need to hold your nose to pack. The epiglotis should take care of that. The way you're describing forces alot of pressure up the eustachian tubes with every pack. Maybe that's why your ears ended up hurting.
It could help you figure things out trying to pack through your nose.

Good luck

 

[Alun]

yeah, me too...

yes, when I first learned to pack, I could only do it by holding my nose. I soon learned how to do it without holding my nose by controlling my soft palate.... just a matter of practice. Sometime, it will suddenly click and you'll know how to do it! You can even pack through your nose with your mouth shut, but it's not really useful for diving.

alun

 

[hydro]

packing through nose

Packing through nose can be useful in diving. You can pack in the expanding air of the mask and throat during ascent. It just takes a little bit of practice.

 

[Alun]

I experimented with that idea earlier this year, but in the end I found that it was easier just to sniff! I think it depends on how well (quickly) you can pack too - whether you can keep up with the expanding air as you near the surface. For me sniffing is more natural - just down to what you feel comfortable with i guess!

alun