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IANTD course

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Mermaid, Musician and Marketer
Nov 12, 2002
Hi, whilst writing the AIDA UK/PADI SPECIALTY freediver courses, I came across the IANTD Master Freediver Manual. All in all this seems a great book, there is just one weird statement that had me thinking...

right at the end there is a piece about breathing up before a dive. I don't have the book here but is says something along the lines of "if at any time you feel tingling, slightly dizzy or have a metallic taste in your mouth - dive - you are ready"

to me these are signs of hyperventilation - and I get a metallic taste in my mouth just before I samba or BO.... is this statement a mistake?

yikes!!... i didn't spot that when i flicked through it! how did a statement like that find its way into the manual? is that statement written in the latest version? when was the manual printed Sam?
its the manual Ben gave me - printed in 2001
It says that in my IANTD manual and is repeated in my Performance Freedivng Manual.

The idea was to stop your breathing and just go before you put yourself into a hyperventialtion situation- I think. Another good reason to dive with a buddy.

dont try this at home kids :)

i'm guessing the statement is basically saying: "if you think you're beginning to notice the signs of over-ventilation, then don't ventilate any further, just dive right away."

i wouldn't teach that to any freediver.

personally, i think freedivers would be much better advised to abort a dive if they find themselves in that state. the freediver should then just relax and breathe normally for a few minutes, then re-start their preparation. this time taking slower breaths to avoid over-ventilating like before. beginning a dive when you're experiencing those tingly/dizzy symptoms is just asking for a nice big BO... :(
I have read the manual too. If you can’t find the paragraph, please don't forget that there are two manuals; the Freediver manual and the Advanced & Master Freediver. I don't have them currently under reach, but at least in one of them is that sentence.

Personally, I am not in favor of breathing up to the moment of the symptoms. However I do know that most standard breath-ups lead to a mild form of hyperventilation. To that extend I think that in anyway instructors and students could benefit to know the signs and symptoms of hyperventilation, just as a precaution.

Perhaps more important from how it is written in the manuals, does someone know how this issue have been handled during the related courses?

I'm with you Alum, just relax and wait for a while after the tingling passes.

It may read like that in the PF manual, I'll check mine, but they don't teach it like that.

"if at any time you feel tingling, slightly dizzy or have a metallic taste in your mouth - dive - you are ready"

If properly ventalating, you body will start producing signs/signals that your oxygenated; tingling in the fingers/toes, a warm (dizzy) feeling and sometimes even a metalic taste. Keep in mind that these signals are similar to those produced when Hyperventalating. This is why it is important to know that there is a difference between Ventalation and Hyperventalation. Ventalations are slow, almost rythmic deep, diaphramatic inhalations and exhalations. When teaching the courses, we stress the importance in knowing the difference between the 2. I am currently in the middle of updating/re-writing the manuals, and that is one area that I will be making a more clear distinction.

safe dives to all

i think those symptoms you're describing have nothing to do with being oxygenated, and are nothing more than the effects of hyperventilation. the reason the signals are similar is probably because they're actually the same.

i never experience those symptoms before a dive, only complete mental and physical relaxation and a feeling of confidence. those are the signs i look for.

"if at any time you feel completely relaxed, both mentally and physically and feel confident - dive - you are ready" :)
Well, I've actuall done both to see if there is a difference, and there was for me. I don't hyperventalate. My breathes per min on my breath-up are around 4 per min. If thats hyperventalating, then you got me. I can sit at my desk right now and do a breathe-up and get those symptoms. Its like a warm flush across/through the body, kinda like being dizzy, and tingly in my fingers. I'm not say do your brethe-up untill you get these signs/symptoms, just be aware of them, and provided you haven't been hyperventalating, them start your dive

Quote from Cali: [ If properly ventalating, you body will start producing signs/signals that your oxygenated; tingling in the fingers/toes, a warm (dizzy) feeling and sometimes even a metalic taste ]

I agree with you Alun, but I really doubt if the body produces signals that your oxygenated. Being oxygenated should be a permanent state and therefore signals are not necessary.

I have read that the tingling sensations in the hands, feet, and lips and a light-headed feeling are the initial symptoms of the central nervous system function being affected by the gradual elevatation of the pH of the cerebrospinal fluid. This is caused by hyperventilation and not by oxygenation.

So I can only conclude that IANTD promotes hyperventilation.

Fred S.
If I am not mistaken, the average O2 saturation when breathing air is somewhere between 96-98%. Breathing pure O2 will raise this level to 100% but you won’t feel any signs or show any symptoms of the increased oxygenation. Even breathing O2 under pressure, say at 6m on a decompression stop will not cause you to feel any different unless you are suffering from O2 toxicity, which is a completely different issue.

So why should anyone show symptoms of hyperventilation after doing a breathe up if it’s only related to being oxygenated? I would have to agree with Alun in that I suspect the symptoms described are being caused by Hypercapnia, regardless of how slow and controlled the breathe up was.

I do a very slow and relaxed breathe up for statics but I can get so lightheaded at the start of the static that it takes 30-40 seconds before I start to get back to normal. I get my best times when I get to this stage on the final attempt but it’s definitely not hyperventilation as we know it. I am pretty sure that it's related to Co2 levels. Put it this way, I wouldn’t dive feeling like that.

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I started looking through some of my other books and found this statement in the NAUI: Mastering Breath-hold diving book by Neal and Morrissette:

With any breathing drill or exercise, if at anytime you begin to feel numbness, tingling, faint, lightheaded, dizzy, unsteady, nauseous, or different in any way, stop all activity, rest, breath normally, and if you are in the water- get out!

That's a little different take on the subjcet than the PFD manual and the IANTD book. Actually, it sounds like one of those prescription drug commercials that are on all the time in the States.;)

I appoligize, I was mistaken. The signs/symptoms that can be generated are due to hypocapnia.
my bad

thanks for setting me straight :)
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You can get hypocapnia from breathing slower then 2-3 breaths/min, so the only way to avoid hyperventalating is to let your body breath the way it wants to.
Just my opinion...
hyperoxygenation symptoms

If you get symptoms of this I think I would know about it - 2 weeks in a recompression chamber breathing pure O2 for four hours a day at 18m and I never got any of those symptoms....
you do get numb fingers and toes after all a while but certainly not dizziness and the others listed in the IANTD manual. The only time I ever got those was from hyperventilating...... which I used to do and used to dive more fearlessly... until I learnt the hard way!

Amazed the NAUI have a manual.. ordered my copy already.... project for later this year is to write one to go with my PADI courses..

Hi guys,

Could you compare IANTD freediver courses and Apnea Academy 1st and 2nd levels?
I wrote several times to IANTD International and lots of IANTD freediver instructor, but nobody answer.

Thanks your help.

Don't know about apnea academy but IANTD Master Freediver looks a lot like AIDA *** Freediver
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