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Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Jun 20, 2003
Freediving (more than any sport?) is cloaked in mysteries and contradiction. Can anyone help me clear some of them up?

Anaerobic or Aerobic? "Freediving is 100% anaerobic" (Castineyra), but many (Murat, Pelizzari) cite endurance training as imperative. Some people even get their best results during a trough of aerobic fitness (Fattah, Ivan). Contingent apologies to anyone I have misquoted/misconstrued.
Steak or bird? If freediving is anaerobic then I should be scoffing quick twitch (white) flesh. However to build haemoglobin for O2 storage I needs must eat a family of cows per day, just for the iron. (Forget about iron pills - you don't absorb it unless its in the form of haem)
I can equalise several times per second whilst breathing in or out through nose/mouth/both, with my tongue on my chin. No amount of engineering of epiglottis/soft palate diagrams can evince this... any clues?
Wouldn't the best warmup for a constant weight dive be a negative Buccal? (No limits) This would bring on the dive response without creating any lactic acid, which takes 30-60 minutes to clear.
Does anyone know the coefficients of friction for salt and fresh water?
Eric Fattah mused somewhere that Stig and Topi's dives were the best freedives in history. I agree with Stig's (166m unassisted - where did that come from?) but I think second place has to go to Pelizzaris 150m No Limits. The dive was made in the middle of a Mediterranean storm; Umberto had a 2 hour ride in an inflatable over huge waves to get to the navy boat. He spent the whole of the descent worrying that someone would spot the trickle of bubbles coming from his left ear every time he equalised (he had put a hole in the timpon in his previous dive). On the way up as his sled was travelling too fast he did the last 60m free immersion...
Hi will... i think i can help you solve some misteries :)
freediving is anaerobic. Period. Less than 10 minutes activity has a proporcion up of 90% anaerobic, 10% aerobic. But aerobic training
improves the efficiency of your heart, lungs and capacity to absorb O2 and eliminate CO2, so helps
a lot in the breath-hold time.
So when you freedive, your activity has two components:
a) the muscular effort to take you deep (fin kicks)
b) breath-hold ability

anaerobic training helps a), aerobic training helps b)

Steak or bird? both. Steak (or lentils) for the iron.
white flesh to build and repair muscle.
That´s why are mysteries.
I don´t think that Freediving is 100% anaerobic neither aerobic.
The diving mammals has a lot of oxidative enzimes and Myoglobin in his diving muscles. Why you have oxidative enzimes if you don´t use oxiygen?.
Some statics last 8 minutes, the anaerobic system probably can´t give enough energy for that long period.
Why the oxygen conservative effects of freediving?
I think is like a Heavy exercise, you use both systems.
I am unconvinced that aerobic excercise increases breath-hold ability. Yogis have far and away the best breath-holds, and I doubt their tickers ever get going above 100 bpm.

"Less than 10 minutes activity has a proporcion up of 90% anaerobic, 10% aerobic"
- Excercise depends on quality not duration. You can excercise for less than 10 minutes 100% aerobically as long as the excercise is mild enough.

"Some statics last 8 minutes, the anaerobic system probably can´t give enough energy for that long period. "
- The brain will always be aerobic, and I think smooth muscle is the same. I agree with you that there is probably a mix - in fact I hazard that apnea would begin aerobic and gradually become more anaerobic.

A medical friend recommended liver or black pudding for iron. Neither sounds particularly palatable, but I may look into them...

Thanks for your input Frank and BlueIcarus.
Hi will.
There is something funny, you started this thread looking for help, but I think you just wanted to state your believes. The best way could be to tell us your opinion and we share ours.
You have some confusions.
You don't need to be a superathlete to have a perfect aerobic metabolism, some creatures born with this ability, like seals and dolphins. You don't see any dolphin practicing apnea tables, their genoma is configured for that.
We are not dolphins, so we have to train. But training is not just to do physical work, as you said Yogis work their mind, which is more difficult than body.
If you control your mind you will control your body.
The other are just chemical reactions
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We are all rich with gems of information, but I for one am not a good enough jeweller to tell the real from the fake - hence the request for help...:confused:

If static apnea doesn't use muscular systems at all, then maybe it is possible to train the mind, heart etc to slow down (as yogis must do) such that you could do an 8 minute static or more, but without being able to swim a length of the pool underwater due to muscular anaerobic inefficiency.
In other words the two systems - muscular and mental - are independant and may be trained as such. Static uses mental, while diving uses both mental and muscular.

Aquatic mammals have a greater anaerobic efficiency, which is genetically acquired, but wouldn't there be variations within this sytem also? Also I would be interested to see if dolphins born in captivity (and hence a shallow pool) had equal apnea capacities to those born in the wild.

P.S. Frank I really would like to know what you think about "Wouldn't the best warmup for a constant weight dive be a negative Buccal? (No limits) This would bring on the dive response without creating any lactic acid, which takes 30-60 minutes to clear." What warmup do you use before a dive?
Hi Will,
As I wrote before there many evidence of the highly aerobic capacity of diving mammals. Of course they have good anaerobic capacity also, but I think this is for short dives. Some diving birds don't show the "usual" response in short time dives. And I think the same is for us, in short highly active dives we can relly on our anaerobic capacity. But for long time dives I think the aerobic metabolism is crucial.
What you said about genetics is obviously true. You can born with a perfect aerobic system, but if you don't use it, it will never be as good as it should.
About the "negative buccal" I have my own believe.
What you said is probably true, but I think a variable weight dive will be better.
If you don't use your legs at all, when you start the CW dive the flow in the muscles will be very low, so in the first second you should rely in anaerobic sources of energy, lowering it, and you will need it in the way up. If you do, some light kicking, you will have a better blood flow to the muscles, avoiding the need to use sustrate in a anaerobic fashion (in fact, less efficient) in the early part of the dive.
My warm up is to do 2-3 very shallow CW, with some hanging (not so extreme, to avoid oxygen debt).
The words 'aerobic' exercise and 'anaerobic' exercise are only simplifications for non-scientists. If you look at the metabolic reactions, there is no clear division.

Further, there is great confusion since the word 'aerobic' exercise is used for several different things. Fitness instructors tell you that you must exercise for more than 15 or 20 minutes in order for your 'aerobic' system to 'activate.' This doesn't mean that you exercised for 15 minutes without consuming a single molecule of oxygen (otherwise you could have done the 15 minutes without breathing).

Marine mammal researchers invented the term Aerobic Dive Limit (ADL). This is defined as the maximum depth/time that a mammal can dive to, without having lactic acid accumulation in the muscles. However, this is also a vague idea, since marine mammals have huge amounts of ATP and creatine phosphate in their muscles, which can provide energy without O2 consumption, and without lactic acid production; so even if the mammal surfaces without lactic acid, it may have started to run out of O2 and began consuming ATP/CrP in an 'alactic anaerobic' reaction. So as you see, in the end it all comes down to metabolic reactions, and simplifications such as 'is this aerobic or anaerobic' are meaningless.

However, a more reasonable question is whether you should train for fast twitch muscle fibers, or slow twitch fibers. Again, look to marine mammals. Some seals have up to 80% fast twitch fibers, and store much of their energy as CrP/ATP in those fast twitch muscles. Other seals have up to 90% slow twitch fibers, storing most of their O2 in myoglobin and blood. It is also interesting to note that these two types of seals have different behaviour underwater; one of them tends to attack in rapid bursts of energy, the other doesn't. So it depends on your diving style.

My experience is that both aerobic training for slow twitch, and power training for fast twitch, work for freediving. However, if you train aerobically, you must do everything possible to increase the lactate threshold of your muscles, since you will not have enough ATP/CrP in your muscles to yourself get back to the surface alactically.

However, regardless of how you train, you should try to make the dive itself as anaerobic as possible. The more bloodshifted you are, the less blood flows to your legs. If you were completely blood-shifted, no blood would flow to your legs, and your legs would be forced to consume the energy stored inside them (O2 in the trapped blood, O2 in the myoglobin, CrP/ATP, then glucose + glycogen into lactic acid).

You must prevent your legs from consuming O2 from the main blood pool, because the brain can only run on O2, so all the O2 must be conserved for the brain. This is why you must blood shift as much as possible before diving, hence the popularity of negative pressure dives to warm up.

Without a significant blood shift, fresh blood will pump into your legs, and your legs will consume O2 from that blood, stealing it away from the brain. In general, you will be the most blood shifted at the bottom, during the turn around, and during the ascent. That is why kicking in the start of the dive is VERY EXPENSIVE in terms of O2. The legs are not yet completely vasoconstricted, so those early kicks consume far more O2 than the kicks off the bottom.

Remember Sebastien Murat's rule: If you have a samba/BO at the end of your dive, and your legs did not 'fail' during the dive, then you were not blood shifted enough.

A nice example of this was Mandy Cruickshank's dives for her 71m record attempt. During training she was reaching 67-70m with lots of leg fatigue, and clean surface recoveries. Then, she unconsciously changed her warm up, and didn't blood shift enough. Her next dives to similar depths resulted in blackouts. She then remarked that on the blackout dives, her legs did not get tired AT ALL. Murat's rule was violated. She had a BO without leg failure. In all likelihood, she was not blood shifted enough, and I discussed these ideas with her and she agreed. She then commented on the changes in her warm up, which had included shallower negative pressure dives and a longer interval between her last negative dive and her target dive.

In my case, I have had three blackouts and several sambas from constant weight dives -- in each case my legs did not fail. At the same time, I have had many dives which were extremely difficult, and my legs failed, and even though I didn't think I would make it, I reached the surface clean.

Eric Fattah
BC, Canada
It is always interesting to hear about the many instances in freediving where technique is vastly different but with the same results - the seals are the best example yet.

I had an inkling about the necessity of muscular lactate tolerance - nice to have it confirmed. Is the speed at which we convert lactate to pyruvate pertinent? I know it takes as long as an hour to clear totally, but obviously this will be exponential.

Murat's rule will be referenced well in future - I samba all the time, but have never noticeably failed my legs. I guess the body will acquire a greater rate of MDR onset with familiarity to the dive experience.

Once again obliged for your detailed help Eric, while you're here, do you have any secret formulas for blood building (ie absorbing iron)? Must I acquire a taste for black pudding...?
Eric I agree (your statements works in practice for me) and I have another comment in this and it's about weighting and how this can be optimized along with the facts that you mentioned.

-Some divers prefer to have little weight and in this way they claim that the ascent is easier.

-Other divers (me for instance) like to be relatively more heavy weighted to take advantage of the fact that EARLY ENERGY OUTPUT WILL TAKE MORE O2 OUT OF THE BODY THAN ENERGY OUTPUT AT THE END OF THE DIVE.

This does not mean that I'am sinking at the surface. I am neutral at approx. 8-10m.

Maybe I have so few kicks down to the point when I can relax that I only use ATP/Cp, what do you think Eric?
i used to dive quite light in the water- neutral around 15m. now, i dive like you derelictp - neutral around 9m with full packing. (i wear 1.0kg with a 3mm in freshwater.)
it takes hardly any effort to leave the surface and i stop finning around 17m. one thing i used to do was to graudally reduce finning effort as i became more negative. after a while i realised that this was actually holding me back. it's more efficient to fin at a good speed, then suddenly stop dead. on one dive profile i could see how the action of finning gently was actually slowing me down. my speed instantly increased as soon as i completely stopped finning.
now, when i stop finning around 17m, my initial sinking speed is quite slow - around 0.7... but if you keep streamlined (without too much effort) your speed soon picks up. i normally hit terminal velocity in the late 30s. the amount of O2 you save by diving this way is amazing. with arms by my side during the descent (and ascent) it seems i use hardly any O2 during the descent - almost like a variable weight dive! :)
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It's so fun to hear that you dive exactly in the same way that I do and with the same experience from it!

Arms by my side is very good for relaxation and it makes equalizing easy because it does not stretch my thorax!

Cheers Alun
A very good argument for heavy weighting. Until now, under orders from Pelizzari, I have been diving very buoyant - 3mm with no weight at all. I dive only no-fins, so it is even more of a struggle.

However about the arm position, remember that the most relaxed position has to be orientated to gravity - arms extended in descent and by sides in ascent. This will also allow for a quicker descent. For no-fins it is imperative to maintain balance.

Alun it was interesting to see what you call heavy diving for yourself, 1 kg of lead isnt very much, well at least I didnt think it was.

I use a cressi comp 3.5mm suit and use 13lbs of lead which is probably around 6-6.5kgs this is in saltwater but I didnt think fresh would make such a difference that you only use 1kg. With this suit I can sink from 10m although I dont dive to your depths but was 1kg a typo ;)


Ivan aka heavy diver :D
yes, i did mean 1.0kg - no typo

i can't remember the difference between fresh and salt in terms of lead - 1 or 2kg?? i've hardly ever dived in the sea, so i don't need to know!
it depends on other things too of course, like the size of your lungs and the amount of fat you carry. i'm about 10% fat, but i'd like to blob out a little more (without compromising fitness) - it would help me in the water temperatures we have here.

Im a very small skinny guy only 65kgs and small lung volume so maybe its that extra .5mm of suit I wear that makes me need more leads :D

1kg of lead would be too hard to get below the surface for me

I like to dive heavy. I've done some good dives undeweighted, but they weren't that pleasant. I wear 4kgs with a 5mm 2 piece farmer john Picasso. Herbert says he wears 3kg with a 3mm. If you watch any of his dives, he needs his coach to hold him up during breathup so that he doesn't sink during the exhale phase.
Erik Y.

When I do the dinamic not fins in pool In winter time -I use my 3mm wet suit and 6 pounds-I do with it 70 meters...I feel like the water is to cold for me ...in summer time I only use my 3 pounds...and I can see a big different ..


i would also have that problem of sinking below the surface if i prepared on my back or vertically. instead i do my 2-3min dive preparation through a snorkel, so i don't suffer the problem. i've learned to pack really fast through the snorkel - in about 8-10secs.

i think preparing vertically has benefit in that it helps to maintain the blood shift. i think preparing on your back has the benefit of being easy to breathe deeply and pack.

...but i think it can be difficult ot relax when preparing vertically, especially when sinking on the exhale - you have to hang on to something or someone! it can also be difficult to relax on your back when heavy as Erik said, plus then you have to change position before diving.
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