Dan,
Please read this entire article, and pay attention to Table 1. Also pay attention to the concept of "Equivalent Depth" described on page 7. Here's the article:
An Atypical Case of Taravana Syndrome in a Breath-Hold Underwater Fishing Champion: A Case Report
For some reason unknown to me, the link takes you to page 9. You'll have to use the arrows at the bottom left to get to the beginning of the article.
SeaRat
JOhn,
Thanks for the article....
It actually gives credence to what I had always suspected, that if you are going to deep drops, you need long surface intervals between them....that just because some freedivers are capable of doing a 3 minute or more drop, than a 3 minute surface internal or LESS, and then going back down for another deep drop, is NO reason to actually do it. It makes total sense that you will begin to grow bubbles, or "seeds" with each deep drop.....which gets the whole issue looking more like a scuba diver that is not using long enough surface intervals...or that has some bubbling going on, and then on the SI, decides to do a couple of deep drop freedives between scuba dives.
I think if this ever gets studied in depth, there will be very large differences between "some" individuals and the "average" individuals....suggesting there may one day be some genetic markers for people with some of the mammalian genes which are far more utilized by seals or dolphins. Without going on too far of a tangent, in the late 70's to the early 90's, I did a great deal of diving with the First diver and dive operation owner of Palm Beach---Living dive legend Frank Hammett( was scuba diving Palm beach from around 1955--about a year after when Gagnon invented the Aqua Lung) ....Even into his 60's, Frank could dive the Hole in the Wall on a single al 80 ( depth to 135 feet), shoot fish till he ran OOA....Free ascend to surface, grab another tank, then immediately go back down and shoot till OOA again. I do not believe Frank EVER felt the need to visit a chamber....that he was ever bent enough to know it--or at all. He remains mentally sharp to this day, and in his 60's he was still the fastest swimming diver I had ever met.
Beyond Frank Hammett, George Irvine of the WKPP had/has an ability to off-gas at a level far off the charts when compared to the Us Navy Tables. This led to George and Bill Mee and Dr Bill Hamilton, developing "Special" trimix tables for George to use on 6 hour long bottom time dives at depths averaging 280 feet deep. Deco for this for George would be around 11 or 12 hours--far from the prediction of the Navy tables, and the successful use of these tables by George and JJ and other WKPP members led to Navy Spec Warfare, being onsite for many of the big dives George and JJ did.
George's personal tables were extended for use by others, using VO2 max...a measure that correlated well to overall perfusion and adaptations to intense cardiovascular training, and others would have a multiplier from VO2 max shift their personal tables to the appropriate degree of less aggressive off-gassing, based on the assumptions from their correlated perfusion....
I was, and still am, able to use George's tables today, for 100 foot to 300 foot dives, without any change for Vo2 max--as George and I were close...mine being a bit higher than his in the 90's. He was a competitive Masters Swimmer, I was a racing cyclist ..both require intense peripheral adaptation to training. We assume this is responsible for the faster off-gassing schedules that the WKPP tables utilize.
Point being....for freediving, I see there is powerful evidence now that a form of tables needs to be developed...and that behaviors need to follow this.
I will likely be doing more deep freediving in the near future, due to some of the opportunities in diving I now have, so I plan on looking in to this a great deal more closely...
Having Bill Mee as a dive buddy and close friend, also means I will have him working on some form of table development for my freedivng
---------- Post added October 19th, 2015 at 09:43 AM ----------
*** Notes on this
I am not a fan of "tables for everyone"...I was able to see in the WKPP tables, that George could actually make a tech dive safer for him and me, using his schedule, than the dive would have been for us using the Navy Tables...( or the present PADI or GUE tables)...So I do think some factor needs to customize any new table, to the individual.
Tables like what PADI uses are a very bad start of any new science on this, as they include fudge factors such as poor cardio fitness, as well as fudge factors to deal with the 25% of the population that has a PFO--this being a group which obviously needs to be EXCLUDED for the purposes of finding and ideal set of tables for an individual without medical problems.
If ever someone is able to find a genetic Marker for this mammalian gene that makes the person able to off-gas so far from the general distribution as to make no sense whatsoever ( call this the Hammett Gene
, then this needs to be recognized, and far more doppler and other studies need to be done on each of these people, with hopes of gaining insights as to what types of off-gassing schedules they could actually use.