The theory that Sebastien has put forward is completely logical with our present understanding (mostly based on theory and experience, not published experiments), and the references Sebastien stated FULLY support his theory. This is why I am amazed at the stuff that is coming from Simon Mitchell. I agree with some of the safety concerns taht he states, but not that this method of diving is 'physiologically wrong' (not a direct quote). I hope that he will appreciate during the course of the discussion there that it is not just Sebastien that is doing this, but dozens (or more) or people around the world (all experienced freedivers) are finding the benfits of this manner of diving.
SM stated that Marine mammals can do what they do due to large O2 stores and that we as humans don't have them, ergo we cannot dive this way. This is not Logical.
The logic should be: Marine mammals can dive so well this way due to the large O2 stores they have, and that we as humans don't have such large stores that we cannot perform to the same level.
But Sebastien never said any of these things. He never claimed he could dive as deep or as long as a Sperm Whale or Elephant seal. He claimed that there is logic to why this method of diving could be useful to humans. That's essentially all he is saying (and proving by his actions, along with many other freedivers).
This is a long standing problem in breath hold diving, in that theory and experience are sooooooo far ahead of published experimental research, that published research will take decades to ever catch up with where we are now. I know that Sebastien is trying to bridge that gap.
Eric was absolutely right to point out that 'No research has been published on human exhale breath hold diving [this will change as Seb publishes his findings] and thus there is no research that supports nor disproves Sebastien's theories. The only relevant evidence is that Marine mammals gain advantages (and disadvantages) from this kind of diving and thus, unless proven otherwise, there is no reason to think that Sebastien's theories are incorrect.
As an (ex)physiologist, I agree with the theory.
As a freediver, who has been diving with these techniques for over a year now, I find that it works in real life (and I'm still here
).
I don't see that there is anything more to say, and I find it saddening that a respected physician jumps up and down to denounce Sebastien, before taking the time to fully understand what he is saying, although to reiterate, I think his safety concerns are fair, just inappropriately presented.
I'm off to Orkney freediving for the weekend, so I'll be interested to see if this all calms down by next week.