Packing Hypercapnia

[holdown]

Why when I pack do I often have all the tell signs of hypercapnia? Additionally, I often pack and then do stretches to loosen up my rib cage. One of these stretches invloves bending over (i'm sitting with my feet under my butt, knees in front) with my fists at the base of my thighs, this, in theory, compresses the air into my thoracic cavity, stretching my ribcage. However, it invaribly makes my head feel as if it were about to explode and I can't do it for more than a few seconds, without bursting a vessel. Should this be so, and/or are there other recommended techniques for mantaining ribcage flexibility? Thanks for any imput, David (I actually find packing and then swimming a 50 hypoxic stretches things out pretty well)

 

[trux]

Well, packing is indeed a very contraversial method, and bears considerable risks with, even if performed just for stretching in moderated levels. Diverse risks of packing were discussed many times here. You can find a collection of such links for example in this post: http://forums.deeperblue.net/safety/65340-dangers-dry-apnea.html#post630454

You will find even much more if you enter packing into the search box above in the menu.

 

[SEDATE]

my idea after packing and holding breathold kills DR
... but very useful doing 10 minutes before apnea, it makes our rib cage expand and give us a big advantage
me i do packing 2-3 times 10min before max hold and resting and directly going breathhold without warm up i mean big inhale 80%-85% fill and max hold ,
trux you do packing before max hold? or what kind of way you using before max hold?

 

[trux]

trux you do packing before max hold? or what kind of way you using before max hold?

Well, myself I am not really a reference for anyone here. I am just trying to point out that packing is a technique that should not be used without fully understanding the risks it represents, regardless if used for max performances or just for stretching. I am concerned seeing young beginning freedivers with huge reserves elsewhere, using the technique without even getting any information about possible damage it can cause.

Among the risks and disadvantages often quoted in diverse DB discussions, you can find these ones:

• Risk of immediate blackout [i.e. here]
• Initial tachycardia (increased heart rate) and reduced blood flow (due to the heart crashing by lungs)
• Suppression of the Diving Reflex
• Risk of barotrauma, generally (some specific cases below)
• Risk of pneumomediastinum - [here]
• Risk of embolia or air-trapping [i.e here]
• Long term increase of the residual lung volume [i.e. here]
• And paradoxically also increased risk of lung squeeze [i.e. here]
  - this is especially important to know, since many freedivers use packing just to avoid lung squeeze at deep dives

Each freediver who wants to employ such technique should be sure to go through the above linked threads and make sure he/she understands the involved risks. Also looking at some scientific papers like the ones linked below may be worth of reading. Freedivers who use to pack extremely should consider making regular checks at a pulmonologist.

• Features of glossopharyngeal breathing in breath-hold divers
• Features of glossopharyngeal breathing in breath-hold divers
• Respiratory mechanics during glossopharyngeal breathing in competitive breath-hold divers.
• Cardiovascular Effects Of "Buccal Pumping" In Breath-Hold Divers
• Studies on inspiratory and expiratory glossopharyngeal breathing in breath-hold divers employing magnetic resonance imaging and spirometry
• Apnoetauchen – Physiologie und Pathophysiologie
• Andhållningsdykning – en växande äventyrssport med medicinska risker

 

[SEDATE]

thnx trux , i agree with you totally but this below is really interesting !!!!
............
Here we report a pneumomediastinum found on chest CT scan in a diver during a physiological study, when glossopharyngeal insufflation increased the volume of gas in the lungs by 1,040 ml (over his total lung capacity); at the same time, his transpulmonary pressures increased up to 4.1 kPa. We discuss the possibility that the very high transpulmonary pressures during lung packing caused this pneumomediastinum
.............

 

[trux]

Yes, exactly. An additional 1l is quite moderate packing. You can imagine the pressure if you pack to your extrem, and then make some flexes, reducing so the inner ribcage volume - the pressure then grows even much higher and the risk of injury grows too.

 

[shoutatthesky]

"pneumomediastinum"?

I am one of those beginner divers (2nd season) who is just finding out how risky my approach to these sort of techniques was in the beginning. I try to stay away from packing too much now. I do find however that if inhale fully then relax - just holding the breath with my glottis. I can then inhale a little bit more then relax again and repeat 2 or 3 times before I am 'full'. As far as I know this would not be referred to as packing. I can 'pack' by filling my mouth with air then forcing that air into my lungs. I can use this method at least 10 times but like I say I don't like to push it for fear of going too far. What am I doing?

As for all these medical terms - maybe there should be a glossary on this site?

 

[naiad]

I can 'pack' by filling my mouth with air then forcing that air into my lungs. I can use this method at least 10 times but like I say I don't like to push it for fear of going too far. What am I doing?

That is packing.

Additionally, I often pack and then do stretches to loosen up my rib cage. One of these stretches invloves bending over (i'm sitting with my feet under my butt, knees in front) with my fists at the base of my thighs, this, in theory, compresses the air into my thoracic cavity, stretching my ribcage. However, it invaribly makes my head feel as if it were about to explode and I can't do it for more than a few seconds, without bursting a vessel.

I am not too happy about pack stretching - I explained why in this post. I know that it is very popular among freedivers, but I am scared to do it, even though I can pack quite heavily.

Lucia