Apnea Diet

[Almostafish]

I keep a bottle of Daves insanity chilli in the fridge and use some of that to wake everything up before a days diving. Be warned though its qute extreme but clears the tubes like a jetwash!

[Absolute]

Raising the blood pH before a static will increase the co2 tolerance for the apneist. So do your normal co2 tolerance training and before you try to set a pb static eat a few lemons an hour or two before to give you that "extra" co2 tolerance on top of what you already have adapted to.

Eating 5 lemons a day would not be the alternative to normal co2 training.

[Sealdiver]

For Samdive,
To be honest, i just heard that in a health and fitness journal that green tea compared to coffee or normal tea tends to slow release the caffine content. I'm not to sure on the science of it but ive heard it is the better option.
peace, Sealdiver

[octopus]

I could not find any articles that refer to prolonged apnea like in freediving - with respect to pH level and vitamin C level in the blood.

The pH (acidity level) of the blood monitors the level of carbon dioxide (CO2) within the blood. Many physical processes influence your pH levels, but one of the largest contributors is the CO2 content of the blood. As CO2 levels increase, the concentration of H+ ions also increases, and more H+ means more acid and a lower blood pH. This acidic state signals your brain that you need to breathe faster or deeper. Under prolonged oxygen deprivation conditions such as heavy air pollution and ozone warnings, lung illnesses, or extended periods at high elevations, your body balances its blood pH by increasing the bicarbonate level (alkaline HCO3-).

A balanced body pH is 6.4 and normal blood pH is tightly regulated between 7.35 and 7.45, while pH for a body of fresh water or a freshwater aquarium is 7.0.

So, if you do not breathe, your pH level drops (goes acidic). But body tries to regulate it back to 7.35-7.45. Can body use vitamin C to regulate blood pH levels? (I know it is used as anti-oxidant when anti-bodies destroy bacteria/viruses with oxidants). In that case if you eat lots of lemons, your body would have more reserves of vitamin C to regulate blood pH level, thus delaying the urge to breathe? (Under normal conditions it does not matter if you eat ten lemons, your blood level of vitamin C will not change).

I am guessing very much here and it would be helpfull if someone more knowledgable could clarify this. Thanks.

[jome]

I think the theory was mostly that Citric acid, through some mystery (to me) metabolic cycle increases blood ph. I think this is in line with the popular "acidic vs. alkaline diet"-branch of nutritional awareness. You will find in most references that lemon and grape fruit are considered "alkaline foods", ie. they increase the body ph. It is believed that a higher ph has a lot of beneficial health effects.

Obviously having a more alkaline blood in the beginning of the breath hold would delay the breathing reflex. It is not totally agreed upon that it would increase your breath hold time though, in fact I thought it was the more popular theory that having a low blood ph helps oxygen unbind from haemoglobin and prolongs the breath hold. Maybe I'm missing something here, but to me it seems that the effect would be similar to hyperventilation with and without some of the side effects.

I think that the whole alkaline diet thing is generally thought of being in the "pseudo-science land". It is generally agreed that messing with the delicate ph-balance has serious effects to one way or the other. But which foods are alkaline, which are acidic, and what is the ideal body ph is a bit scetchy (my limited understanding from some quick googling). But I must admit I don't know enough of the subject to make a sound opinnion. Someone with more background info might enlighten us?

I don't think vitamin c has much to do with it, or perhaps there is confusion regarding Citric Acid vs Ascorbic Acid (vitamin c)

[octopus]

I think that the whole alkaline diet thing is generally thought of being in the "pseudo-science land".

It looks like it:
http://www.quackwatch.org/01Quackery...SH/coral2.html

[jome]

Well, if what dr. Mirkin suggests all the piss ph tests I've seen in alkaline diet sites would be useless. But the tone of that article keeps me on my toes. We've seen that sort of thing in the past...In fact I think he's not completely in tune with the concept. He seems to suggest that eating acid won't acidify or drinking alkaline water won't make you more alkaline. But what the "alkaline diet" people suggest is that through cell level metabolism, some food agents such as citirc acid affect blood ph. Go figure, I'm no expert...

So, who's going to eat 5 lemons and measure ph from the blood for us?

[island_sands]

Originally Posted by Almostafish

I keep a bottle of Daves insanity chilli in the fridge and use some of that to wake everything up before a days diving. Be warned though its qute extreme but clears the tubes like a jetwash!

Crumbs... that would give me bum gravy

[SanSan]

Originally Posted by jome

I thought it was the more popular theory that having a low blood ph helps oxygen unbind from haemoglobin and prolongs the breath hold

As far as I understand this is based on the Bohr effect and that would suggest the opposite. So high blood PH should help to unbind oxygen from hemoglobin.

[DeepThought]

Great linnk octopus, explains a lot, even if a bit extreme and counters some other people's evidences.

Originally Posted by SanSan

As far as I understand this is based on the Bohr effect and that would suggest the opposite. So high blood PH should help to unbind oxygen from hemoglobin.

The exact opposite as I understood: http://en.wikipedia.org/wiki/Bohr_effect

Originally Posted by Jome

I thought it was the more popular theory that having a low blood ph helps oxygen unbind from haemoglobin and prolongs the breath hold. Maybe I'm missing something here, but to me it seems that the effect would be similar to hyperventilation with and without some of the side effects.

Thing is that there might be more than just acidity that activates the dive response, maybe high levels of buffered CO2 still activate some responses while delaying some others (like the urge to breath). Am in the lack of knowledge about that as well.
I think that idealy, if it wasn't delaying the diving response, one would want a drastic change in blood pH during the hold, as blood being acidic is important only to the end of the hold when the SaO2 is low and you want the PaO2 to be high (bohr effect). At the begning of the hold one would want the blood alkaline so it won't let the tissues spend as much O2.
From my poor memory of analitical chemistry, having less buffers will make a drastic pH change for the same amount of "acid' (CO2) easier, no?

[efattah]

Citric acid is a precursor to bicarbonate, so eating citric acid will increase your bicarbonate level, which is the primary CO2 buffer.

Hyperventilating will not have the same effect. True, hyperventilating makes you more alkaline, but it also reduces CO2.

You want CO2, because of the vasodilating effect it has near the end of the static. CO2 also effects the release of O2 from hemoglobin, but that is more a pH effect in general, and not 100% dependent on CO2.

So, if you imagine two people starting their static with the same pH, but achieved through different means, they will not reach the same time in the end. Whoever starts with more CO2 will win, given the same starting pH. For this reason, huge amounts of citric acid allow you to start with more and more CO2, and still start at the same pH that you used to start at.

A 'therapeutic' dose of citric acid for static is about 10g. Mixing into gatorade makes it palatable. The alternative is a lot of lemons.

[SanSan]

Originally Posted by DeepThought

Quote:
Originally Posted by SanSan
As far as I understand this is based on the Bohr effect and that would suggest the opposite. So high blood PH should help to unbind oxygen from hemoglobin.
The exact opposite as I understood: http://en.wikipedia.org/wiki/Bohr_effect

Yep I thought high PH is acidic and low PH is alkaline. Looked it up http://en.wikipedia.org/wiki/PH and now I know its the opposite.

[octopus]

http://www.usyd.edu.au/su/anaes/lect...b/control.html

It is slowly getting clearer. Let's keep it going.

[Ceri118]

Hello all ,
Mostly just hang around the spearfishing pages so I might be a bit out of my depth here . (No joke intended !).

I've Tried having a lemon before I go in the water and found it to be very effective , I squeeze a whole lemon into a cup of green tea and have it before I go out.

That thing with eating the hotdogs , I'm always open to new Ideas but I don't know if any body has tried a Nitric Oxide supplement you can get.

I've used it in the past for weight training along with loads of other crap to little effect , but I have not done any real tests with it with relation to the water.

The stuff I used was NO/XS by higher power nutrition.

You can look it up at www.bodybuilding.com

[watts]

Has anyone had any experience with Octacosanol?
# Found in wheatgerm, alfalfa, sugarcane as a waxy substance
# The active ingredient in wheat germ oil
# Especially effective in increasing endurance, stamina, vigour and reducing the oxygen needs of the body
Octacosanol is known to increase and improve glycogen storage in the muscle tissue, also increasing the utilization of oxygen and tissue oxygen saturation.


Thanks Nathan Watts