do you use a snorkel?

[Simos]

As a fitness trainer, you may be interested to know of the latest research done on breathing.

Most of the research is done on aththletes but some may rub over in`to freedivers.

CO2 build up in snorkles. I would be interested to know where the extra CO2 is coming from. Snorkles these days are bottom purged, meaning your exhilation is going out the bottom not up the snorkle. There should be air in the snorkle.

CO2 fallacy, there is only around .03% CO2 in the atmosphere when you breathe in you don't breathe in much CO2.

Most of the CO2 is in your exhilation and people think they need to breathe out heavily to remove as much CO2 as possible. And they are correct, except your blood PH is regulated by the level of CO2 in your blood stream.

How does your blood know where to drop the oxygen into the muscles that require it?

Well, your blood holds on to oxygen when it hasd a high PH. When it reaches the muscles that are working, the CO2 enters the bloodstream and drops the PH. As the blood can't hold oxygen at a low PH it releases the oxygen into the muscles.

If you exhale too much CO2 the PH of the blood is so high that the oxygen will not be released. This will cause muscle fatigue.

Slow gentle breathing using the diaphram to breathe is now recommended for athletes.

I realise that we are also talking breath holding here which is not what athletes do, but that information may be of interest to you.

Poida

Don't want to go too much off topic on this Poida but the Bohr effect etc are well known to freedivers and they're relevant to hyperventilation - there are many threads on DB on this if you are interested.

Regarding the CO2 buildup, I guess the 'worry' is that when you breath through the snorkel instead of breathing in 100% fresh air, you breathe back in some of the air you exhaled which is higher on CO2 etc. If I remember correctly in AIDA courses they recommend a 'short' straight snorkel with big diameter but I'd guess that if you bought any half-decent snorkel it should be ok.

Maybe some cheap snorkels with problematic designs might cause an issue with CO2 hence the warning... I remember as a kid seeing some odd things, for example one of my friends had a mask that had a snorkel connected to the top and you were breathing in and out through the nose and I seem to remember some kind of ping-pong ball design at the end of the snorkel to keep it dry (snorkel end was facing down, ping pong ball would float and seal the end when submerged)

 

[Poida]

Jeez Simo you must be as old as me if you can remember ping pong balls on the end of snorkles.

They were banned in this part of the world due to sea grass etc. getting in the ball mechanism and allowing the snorkle to fill with water. The user thinking there was an empty snorkle sucked in a lung full of water.

Of course the Bohrs effect is what I was talking about, and although it was disscovered (if that is the right word) earlier 1900s it has been ignored to a great degree. I'm pleased to hear that it is a factor in freediving.

I am not an experienced freediver, not as length of breathholding goes, and only brought my comments to the fore due to the CO2 build up factor.

People think that CO2 is an enemy but as you already know, obviously due to your knowledge of the Bohrs effect that CO2 is an important factor in Oxygen distribution.

I didn't expect statements such as "Have you ever used a snorkle," from our friend Efattah. When you purge the water out of your snorkle, what replaces the water. Ah, a vacuum, he's still uses a ping pong ball.:hmm

Thanks anyway Simo I'll try and find more on earlier threads as to apneaism.

Poida

 

[efattah]

I didn't expect statements such as "Have you ever used a snorkle," from our friend Efattah. When you purge the water out of your snorkle, what replaces the water. Ah, a vacuum, he's still uses a ping pong ball.:hmm
Poida

Poida,

I find your comments more and more offensive. Under normal conditions, obviously, no water gets into the snorkel. If you purge the snorkel, what replaces the water? Air from your lungs, laced with CO2. Either way, the purge valve will never cause the introduction of any 'fresh' air into the snorkel.

You seem to think that because you are a fitness trainer it makes you an expert on freediving. The truth is that freediving physiology and techniques are highly specialized and unlikely to be known by 'fitness' specialists. If you spend some time searching the forum archives, you will find a lot of useful, specialized information that is decades ahead of any published research.

 

[ptoot]

@efattah: Eric, could you describe in further detail how you do your breathe-up through your snorkel. You wrote:

When breathing through a snorkel, the ideal breathing pattern is 1-4 very deep breaths, followed by a 'hold' at the top of the next breath for 5-10 seconds.

Before a CWT dive, do you do normal tidal breathing first, then this pattern, followed by a complete purge breath and full inhale (with or without packs)? I would be really interested to know your complete preparation.

Personally, when I can't hang from a buoy or a tight rope, I find it difficult to have a nice sinal, tidal breathe-up; instead I do deeper inspirations and normal expirations in order to stay well buoyant and keeping my snorkel dry.

 

[BennyB]

Guys please respect each other's opinions and try to avoid inflammatory statements. We are, after all talking about snorkels - not middle east politics... :hmm

 

[Fondueset]

Wow. This thread is still alive?! Given the very widespread and longstanding use of snorkels by freedivers - competitively and recreationally - I would think the idea that potentially toxic or even nominally problematic CO2 buildup occurs with them would have been thoroughly discredited by now.

Perhaps someone can calculate the total volume of potential CO2 a snorkel could hold relative to the lungs - taking into account diffusion caused by turbulence, the presence or absence of purge valves etc. etc. Then we could develop some sort of algorithm to enable us to know precisely how much we should overbreathe in order to compensate for this nefarious pollutant.

Not to put too fine a point on it - but with experience one learns to feel one's state relative to CO2/O2 - and to adjust breathing accordingly. Doubtless, to the extent there is any significant CO2 in a snorkel - we compensate. Possibly it would be a problem if we were trying to purge ourselves of every molecule of CO2, but we are not.

It reminds me of something William Chen (Taiji master) said. We were discussing the saying from the classics that a Taiji practitioner develops sensitivity such that, if a fly should land on his/her hand, it cannot take off again because the practitioners whole body will shift with the pressure. Specifically this was in the context of a discussion about competitive fighting with gloves; Chen asserted that, gloves on or off, the fly weighs the same.

When I first began freediving I rapidly discovered the original big-barrel snorkel developed by Dacor - about the same time Farallon came out with a similar product. These had no valves. I used the technique mentioned here of leaving the snork in and letting the expanding air clear the snorkel almost effortlessly in the last meter or so of a dive. Now that I prefer to take my snorkel out its a little more awkward as I have to tilt the snorkel up and let the water run out - otherwise theres always that bit in there rattling around. These snorkels still breath very nicely however.

I'm sure Eric will answer the breathe-up question - but I can say that part of reason he likes the Impulse snorkels is that they really do shed water very effectively. Such that even a small wave over the top is practically unnoticeable. They are very good during open water breatheups. Likewise for surface swimming with a monofin.

There have been snorkels designed under the premise that the CO2 in the tube was a problem - these vary from designs with scrubbers to designs with two channels and a valve that switches between them. If you're that concerned about it get one of these contraptions and save yourself some sleepless nights. (actually owned one of Snorkel Bob's original MoFlo snorkels)

http://snorkelbob.com/cgi-local/SoftCart.exe/online-store/scstore/moflo.htm?L+scstore+nxxg2518ff02cf02+1322163000

 

[JennyWren]

For recreational diving and warm-up line diving I just use a very basic Omer Zoom snorkel. No purge thingy, no fancy stuff on the tube to stop the water getting in, comfortable mouthpiece, slightly flexible so quite durable. I used to have a snorkel with a purge valve and it just caused me problems, would get stuff in it, etc, start leaking, whatnot. Never had any issues with my Omer, it's easy to clear if a wave comes over the top, and for recreational I can leave it attached to my mask when I dive (I do not keep it in my mouth) and I pretty much never notice that it's there as there's not too much drag.

For competitive line diving, I breathe up on my back (more comfy breathing for me, and I have a routine which involves having a little smile at the sun before I turn over....) and have the snorkel off.

 

[Simos]

For recreational diving and warm-up line diving I just use a very basic Omer Zoom snorkel. No purge thingy, no fancy stuff on the tube to stop the water getting in, comfortable mouthpiece, slightly flexible so quite durable. I used to have a snorkel with a purge valve and it just caused me problems, would get stuff in it, etc, start leaking, whatnot. Never had any issues with my Omer, it's easy to clear if a wave comes over the top, and for recreational I can leave it attached to my mask when I dive (I do not keep it in my mouth) and I pretty much never notice that it's there as there's not too much drag.

For competitive line diving, I breathe up on my back (more comfy breathing for me, and I have a routine which involves having a little smile at the sun before I turn over....) and have the snorkel off.

The very few times that I use a snorkel, I use an Omer Zoom too - if you are looking for something simple that just works I'd recommend it, it does what it says on the tin.

The other advantage (if i remember well, been a while since i used it) is that it floats so you could simply leave it on the surface as you duck dive for your buddy to pick up (otherwise you'd need to attach a small float to the snorkel)

I did find it a bit annoying at times while diving though, seem to remember it vibrating...

 

[Fondueset]

Pah! tiny freakin diameter. AND DIAMETER MATTERS!

No matter what they tell ya.

Now the new sporasub snork:

http://www.sporasub.com/breeze_frame.html?lingua=ING

- that bitch got diameter - that and the old farallons and the impulse.

 

[ReefTroll]

That looks like my snorkel there. I love the thing, has enough diameter to breath up between attacks in a game of underwater hockey.
The Sporasub that is.

 

[Poida]

Yes Fondueset, the CO2 buildup in a snorkle is a myth otherwise we would have lots of people passing out when snorkling. It is not like breathing into a paper bag.

Your blood absorbes Oxygen from your lungs when you breathe in, not CO2. Your blood releases CO2 when you exhale.

Air contains 21% oxygen, your blood to be staurated with Oxygen only needs 5% of it. You exhale 16%.

Got to go.

Problem at mill, so they say, back to work.

Poida

 

[Fondueset]

:head?!:mute

 

[Erdi]

You don't NEED a snorkel for plain free diving. However, it can be useful to have one for certain times:

Safety diving (being able to watch the descent and ascent of your buddy and doing breathe-up simultaneously)
Swimming on surface for long distances (saves having to keep turning around when on your back to see if you're going the right way)
Breathe-up on your front if it's quite 'choppy' / wavey, although usually if you're calm enough, in a wetsuit your body would just flow with the water.
Beathe-up on your front if you find it more relaxing than on your back.

The 'snorkel' used for all events mentioned above would be best if it can float, never actually attached onto your mask. It definitely helps with drag etc as mentioned in this thread.

The only time I ever used a snorkel attached to my mask is for underwater hockey and spearfishing. (I'd use a floating one for spearfishing too if I dived deeper than 10-13m)

 

[BennyB]

Pah! tiny freakin diameter. AND DIAMETER MATTERS!

No matter what they tell ya.

I've always said that girth is much more important than length...

 

[ReefTroll]

It's ok Benny, I'll tell em all the pool was cold.

 

[ptoot]

Yes Fondueset, the CO2 buildup in a snorkle is a myth otherwise we would have lots of people passing out when snorkling. It is not like breathing into a paper bag.

Your blood absorbes Oxygen from your lungs when you breathe in, not CO2. Your blood releases CO2 when you exhale.

Air contains 21% oxygen, your blood to be staurated with Oxygen only needs 5% of it. You exhale 16%.
Poida

I don't think anyone fears large negative CO2 buildups from breathing through a snorkel. I don't think that's the point here.

(Analogy: You will not pass out from 1 glass of beer :friday, but the presence of alcohol in your blood still has its effects)

A snorkel does increase the 'dead space', and if we practice a tidal breathing of -say- half a litre, it makes a difference whether a quarter of that quantity passes through a tube or through open air.

When I do laps on a snorkel in the pool, it feels easier and I recover quicker when I had been exhaling through my nose.

Exhaling through your nose requires more effort from your respiratory muscles though (tightness of the headstrap or noseclip) and when wearing a hood, you could gradually inflate it and it is not easy to stay tidal with the added resistence. The big advantage is that you will not be inhaling any CO2.

If your tidal breath is 500cc and the snorkel is 125cc, this 125cc would contain 16% O2 and 5% CO2 at exhale. At inhale, you would take in 375cc of 21% O2. Theoretically, your tidal mix at inhale would be 75% normal air and 25% recycled air.

So: 1.25% residual CO2 and 19.75% O2 in every breath if breathing tidal from a 125cc snorkel as an alternative to no residual CO2 and 21% O2 if breathing on your back. Now 1.25% does not seem a lot, but only 21% of of the inspired air matters.

If I made any errors in my calculation or assumptions, please let me know.
I left the residual lung volume and volume of airways out of the equation.

 

[pingshui]

I don't think the Omer Zoom floates. I use it (the transparent one) and once I somehow lost it and could not see it on the surface. After searching the bottom for 20 minutes I finally found it in 6m depth. Since then I have a small piece of styrofoam, like from a pool noodle, attached to it. This way I can safely leave it floating on the surface.
Once I also tried attaching a rubber duck to it, but that didn't work too well.

 

[Waterysmile]

I don't think the Omer Zoom floates. I use it (the transparent one) and once I somehow lost it and could not see it on the surface. After searching the bottom for 20 minutes I finally found it in 6m depth. Since then I have a small piece of styrofoam, like from a pool noodle, attached to it. This way I can safely leave it floating on the surface.
Once I also tried attaching a rubber duck to it, but that didn't work too well.

The trick that I was told was to attach bubblewrap to the snorkel using tape; this has served me very well although I usually just carry the snorkel in my hand.

 

[Poida]

You could stuff the bubble wrap down the centre of the snorkle.
Not only will it float but you'll also stop the CO2 buildup.:blackeye