Hyperventilation

[trux]

Originally Posted by hteas

Trux, two new divers here have had Performance classes recently, and both were taught to do 15 hyperventilations before doing their static. It's beyond me!

Well, I understand that is is much easier for a newbie to hold the breath longer after a hyperventilation, but it is counterproductive (not speaking about the risk of BO, of course), so I am really surprised about hearing this. Is it the same for FIT courses too?

[DiverTodd]

No, PFI does NOT teach hyperventilation! They DO teach purging, and they are also VERY careful to explain the differences between purging and HV! They also discourage even doing purging until the Advanced level. TRUST me on this, I've been through TWO PFI courses (I was even one of Mandy-Rae's safety freedivers on her world record dive last year), and one FIT course (and going back down to dive with Martin and co. in two weeks).

Todd

[trux]

Todd, purging is also a kind of hyperventilation - just like any other type of ventilation reducing your CO2 level below normal (and the purge breath serves exactly to do that). And if freedivers are being taught to do 15 purge breaths (as Howard claims), then it already sounds like a pretty serious hyperventilation.

Well, if it is done in a safe environment and taught not to be used otherwise, it is not too bad, but it is actually considered counterproductive since it delays the onset and the strength of the diving response. So although it helps a newbie immensely to come close to his physical limits without too much pain or discomfort, to reach longer times it is actually better learning to cope with the pain and discomfort.

[Erik]

I'll use 'purges' if I'm supervised, which is never anymore haha!
I use Fattah's 1 or 2x 10-second breatholds before the dive to load up a bit extra CO2. I've been using that for years and have never had even a close call as a solo spearo.

[monkeyhatfork]

I'm going to back up DIVER TODD on this, very mild purge, not going to give any specifics cause don't wan't to give away course material, and nothing near 15(can't speak to the advanced course) and dive reflex is fully addressed, and not to be done without supervision. Safety drills make up a good portion of the class.

[ADR]

I'd suggest you do their course and find out or at least ask them directly before flaming them.

Secondly - I have seen course materials for 6 freedive courses and they all teach you to breath fully again(eg 3 stage inhale)......strictly speaking they all therefore teach hyperventilation to varying degrees

[trux]

There is no need for accusations. I do not think anyone is flaming PFI here Quite opposite - I always valued their work highly and am their admirer. I only expressed my surprise after reading the article about Blaine, where the reporter took a course with PFI and was describing his progress while mentioning terms "cycles of purge breathing" and "exhalations to purge carbon dioxide".

If I was ever flaming someone, it was the author of the article, not PFI. You should read all those comments of people (who have no clue about freediving and the safety involved) how they were all eager to know how to increase their breath-holds with the "cycles of purge breathing" and "exhalations to purge carbon dioxide". I found publishing such material a very dangerous deed that may bring some unsuspected kids to a tragedy (despite the final sentence warning people not to try it at home).

This was the reason I asked whether it is true that PFI teaches hyperventilation. So do you really think that trying to find out whether they do it or not, is flaming? Howard answered that two DB members who recently took a PFI course were taught to do 15 hyperventilations before statics. I do not know if they lied or misunderstood the instructions, but am happy that others claim they do not teach hyperventilation or purge breathing to wash out CO2.

As for other courses teaching hyperventilation to varying degrees - yes, I know there are certainly some. As I wrote for a newbie it is the simplest and the most impressive shortcut to breath-hold times he never expected to do. However, personally I prefer teaching newbies in our club the exact opposite - normal or slightly higher CO2 level for the breath-hold. It is certainly the less comfortable way, but I believe that it reduces oxygen consumption and protects you against blackout much better.

[ADR]

Hi Trux

I didn't mean you and I probably should have been more directed...you choose your words very fairly. This is what I was responding to as it assumes correct the recount of two novices and then passes judgement

Originally Posted by hteas

Trux, two new divers here have had Performance classes recently, and both were taught to do 15 hyperventilations before doing their static. It's beyond me!

Howard

[ADR]

BTW - an observation, a question...plus partial judgment

Observation - Anyone who has a pulse oximeter can confirm that normal tidal breathing can produce oxygen saturations in the mid to low 90s and about 2 full more forced breaths will have at about 98/99 after a few seconds

Question - Is this increased saturation through hyperventilation (two forced breaths) detrimental? For it to be detrimental the off gassing of CO2 and therefore the lower blood acidity at the start of breath-hold would have to have a greater impact than the increase oxygen saturation benefits.

Partial judgment - I don’t think we know and why there may be a good safety (belt and braces) basis for saying never breathe more than normal tidal breathing prior to breathe hold it is rarely the practice even for the "no warm up" practitioners.

[trux]

Yes, I completely agree that there is some trade-off, and that most freedivers use hyperventilation to some extend anyway. What I am scared of though is when someone writes an article like the above mentioned one, where he explains to lay public that they can quadruple their breath-holds with deep breathing and purges, and where he does not mention the disadvantages, risks, and side effects of such hyperventilation at all, and only mentions safety in the compulsory-looking footer. It has nothing to do with a freediving course where you get the complete information and safety is very much in the main focus.

[efattah]

Any conscious breathing pattern beyond regular breathing, if done long enough, will blow off the entire body's store of CO2 and eventually cause total hypocapnia and even a hypocapnic blackout.

The reporter explains how their breathe-ups were 'longer and longer' between each hold, with it being very likely that they didn't even 'refill' their CO2 store from each breath hold. As such, the reporter's progress was almost entirely due to gradually decreasing CO2 levels with each successive hold. It makes little difference how forcefully they were breathing. What is much more relevant was *how long* they breathed for.

Trux called David Blaine's previous apnea stunt a 'flop', when in fact it was one of his most successful events ever. His fan base, public image and popularity increased, he developed and got deep sympathy for the planned 'failure', and so on. It was a masterpiece of execution that came to exactly the end that had been planned all along -- even Kirk admitted that at some point. So I don't think it is right to call it a 'flop.'

[azapa]

FYI the "purge breaths" used on my FIT course where more of a supervised example than a "must do" technique, quite the opposite. In fact, I would say Martins teaching is that sense is wonderful: he lets the participant feel the difference in a 100% supervised environment, pool statics, and at the same time clearly states all the dangers. The interesting thing about the purge breaths (OK, mild hyperventilation) in the controlled (pool static) environment is to observe the delayed contractions.

If you take the course material in its whole depth and context, it was very rewarding, and clearly indicative of the perils of hyperventilation.

PS. the "15 purge breaths" is a total myth and not in the course at all.

[DiverTodd]

Exactly, azapa. Even in my PFI Advanced course, I never did more than 10 purges before my target dives, followed by a few normal, relaxed breaths before my peak inhalation.

Todd

[TRITON]

I concur with Eric's opinion.Every ventilation other than normal breathing IS hypervetilation.I've felt this myself many times when trying to breath deep and very slow but eventualy i start to feel "needles nad pins" in my extremities(obvious sign of hyperventilation).Now i just breath normaly(like when i'm sleeping).Only when breathing like that I know that i start the dive with normal level of co2.Since i started breathing like this i haven't had an LMC or a blackout and regularly feel burning in my legs and hands at the end of the dive as a sign of the diving reflex kicking in.

[trux]

Well, technically taken, and letting aside whether it is good or bad, even a single purge breath is hyperventilation. 10 purges sounds already like a pretty serious hyperventilation even if it is followed by a few normal breaths. Now I am not telling you should not do it when in safe environment secured by experienced safety divers, because I know many freedivers do and the hyperventilation prolongs their comfort phase. But I believe it may be dangerous getting used to it, because you will then replicate the same or similar breath-up even when diving in less secure conditions. And I am letting completely aside the fact already mentioned above, that the hypocapnia messes up your diving response and in the end-effect it leads to a quicker oxygen stock depletion.