Hello,
For better or worse, I have come here to clear up a few misconceptions. I am not here to indulge in endless circular arguements. Some of this I posted on Diveoz, but I thought it might as well come directly here.
Let's get a few things clear first.
I do not have any problems with the concepts of marine mammal diving physiology. There seems to be an impression that I disagree with aspects of the accepted and published science of diving by these animals. I don't. However, I do disagree with some of the assumptions that have been made about replicating these characteristics in humans, but I don't wish to provoke discussion about that at this stage.
I do not have any problems with the diving. I am known for radical diving myself.
I do not have any problems with interested divers utilising the exhale technique. Clearly it works, to this point, in a group of focussed exponents anyway.
OK, so what do I have a problem with? It is the way that discussions about this technique in my part of the world have been embellished with "plausible" sounding pseudo-science (I will justify this statement below). Why is this a problem? Well, there are members of the diving public who take what they read on these sites very seriously indeed, and adjust their practice on the basis of this information. It follows that we all have a very real responsibility to present information accurately, and if there are no firm facts to report, then we should admit that we don't know. We must not allow our exuberance or enthusiasm for a technique to seduce us into implying we know more about it than we do. Call me a pedant, but I have been around divers for more than 30 years, and I understand the way their thinking is influenced.
This is what brought me into conflict with Sebastian. I am almost prepared to admit that using "complete fool" in relation to him was not the most tactful way of opening the account, BUT, as someone who dedicates a lot of his time to providing divers with accurate information, I get very angry when I see potentially dangerous (I never said they definitely were dangerous) activities or methods promoted to the public on the basis of incorrect or only partly correct science.
I do understand that participants here will bristle at my claim of incorrect science. But as I said on Diveoz I shall provide the opportunity for one of you to slam dunk me with his better understanding of the field:
I refer to Dr Gowland, whose acid wit has been visited upon me, and who is a recognised expert in the effects of pollution on mussels.
Ben, what I would dearly love you to do for me and your adoring audience here, is to explain in clear and accurate physiological terms how this statement from Seb works in relation to preparation for a deep dive: He says...
"Moreover, exhaling promotes venous return which in itself hastens the rate of O2 diffusion, greatly enhancing venous O2 stores and reducing the arteriovenous O2 difference. This all happens before submersion. Inhaling counteracts these effects."
I contend that this is absolute physiological rubbish, and I have chosen it because it describes an issue pivotal to the technique, (it would seem) and it is typical of a number of statements he has made.
As a former physiologist, I think you know what I am after: a clear step by step breakdown of cause and effect. You know the sort of thing ... " On exhalation from TLC there is a change in intrathoracic pressure from x to y. This results in ...blah blah" This should not be hard because as Seb says, all this takes place before the dive, and the physiology is essentially basic cardiorespiratory stuff (with a bit of head out immersion thrown in) and it's in most of the books. Now, if you can explain it clearly in these sorts of terms, I'll crawl back into my hole and never bother any of you again. It would appear from your earlier posts that you were keen for such an opportunity. If you can't, then all I'm after is an acknowledgement that there may be some problems with the way "you guys" are presenting the basis for your activities to the wider diving community. This has been my only point all along.
Over to you.
For better or worse, I have come here to clear up a few misconceptions. I am not here to indulge in endless circular arguements. Some of this I posted on Diveoz, but I thought it might as well come directly here.
Let's get a few things clear first.
I do not have any problems with the concepts of marine mammal diving physiology. There seems to be an impression that I disagree with aspects of the accepted and published science of diving by these animals. I don't. However, I do disagree with some of the assumptions that have been made about replicating these characteristics in humans, but I don't wish to provoke discussion about that at this stage.
I do not have any problems with the diving. I am known for radical diving myself.
I do not have any problems with interested divers utilising the exhale technique. Clearly it works, to this point, in a group of focussed exponents anyway.
OK, so what do I have a problem with? It is the way that discussions about this technique in my part of the world have been embellished with "plausible" sounding pseudo-science (I will justify this statement below). Why is this a problem? Well, there are members of the diving public who take what they read on these sites very seriously indeed, and adjust their practice on the basis of this information. It follows that we all have a very real responsibility to present information accurately, and if there are no firm facts to report, then we should admit that we don't know. We must not allow our exuberance or enthusiasm for a technique to seduce us into implying we know more about it than we do. Call me a pedant, but I have been around divers for more than 30 years, and I understand the way their thinking is influenced.
This is what brought me into conflict with Sebastian. I am almost prepared to admit that using "complete fool" in relation to him was not the most tactful way of opening the account, BUT, as someone who dedicates a lot of his time to providing divers with accurate information, I get very angry when I see potentially dangerous (I never said they definitely were dangerous) activities or methods promoted to the public on the basis of incorrect or only partly correct science.
I do understand that participants here will bristle at my claim of incorrect science. But as I said on Diveoz I shall provide the opportunity for one of you to slam dunk me with his better understanding of the field:
I refer to Dr Gowland, whose acid wit has been visited upon me, and who is a recognised expert in the effects of pollution on mussels.
Ben, what I would dearly love you to do for me and your adoring audience here, is to explain in clear and accurate physiological terms how this statement from Seb works in relation to preparation for a deep dive: He says...
"Moreover, exhaling promotes venous return which in itself hastens the rate of O2 diffusion, greatly enhancing venous O2 stores and reducing the arteriovenous O2 difference. This all happens before submersion. Inhaling counteracts these effects."
I contend that this is absolute physiological rubbish, and I have chosen it because it describes an issue pivotal to the technique, (it would seem) and it is typical of a number of statements he has made.
As a former physiologist, I think you know what I am after: a clear step by step breakdown of cause and effect. You know the sort of thing ... " On exhalation from TLC there is a change in intrathoracic pressure from x to y. This results in ...blah blah" This should not be hard because as Seb says, all this takes place before the dive, and the physiology is essentially basic cardiorespiratory stuff (with a bit of head out immersion thrown in) and it's in most of the books. Now, if you can explain it clearly in these sorts of terms, I'll crawl back into my hole and never bother any of you again. It would appear from your earlier posts that you were keen for such an opportunity. If you can't, then all I'm after is an acknowledgement that there may be some problems with the way "you guys" are presenting the basis for your activities to the wider diving community. This has been my only point all along.
Over to you.
Last edited: