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Research Study

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.

The Fury

Sultan of swim
Feb 1, 2002
Greetings fellow Freedivers,

I am performing a research study on the effects of Sodium Bicarbonate on Breath-Hold time in Freedivers.
In other sports, much research has been carried out into the effects of substances on performance and many have been banned for ethical and safety reasons. There is no such research with regard to Freediving.
I am looking for people willing to participate as subjects.
Testing takes place at Luton university on two seperate occasions one week apart and sessions can be arranged to suit your schedule.
You do not have to be a competitive Freediver but should be able to hold your breath for a reasonable amount of time i.e. greater than one and a half minutes.

If you are interested and would like to find out more or wish to take part, I would love to hear from you.

Hamish Haughey.
Many freedivers have already tried this. All I can suggest is that the freediver hold his/her breath on top of the toilet, since the sodium bicarbonate causes diarrhea, further amplified by the vagal stimulation of high CO2 levels during the apnea.

Eric Fattah
BC, Canada

I am aware of the possible side effects of sodium bicarbonate ingestion. The risk of the side effects can however be greatly reduced by consuming adequate amounts of water post ingestion. This helps reduce GI discomfort. I have not tested many subjects as yet but of the few that have been tested, none have yet suffered from the runs, vomitting or stomach cramps. Maybe they were just lucky!

The possible side effects are not enough to prevent people from using the substance (or any other ergogenic aid with risks, for instance blood doping or anabolic steroids) in a competitive environment if they think it will give them a winning edge.

We all know that Freediving can be a very safe and rewarding sport provided the few safety rules are observed.

There is, however, no research into ergogenic aids with reference to Freediving despite the huge capacity for tragedy. I plan to investigate many others during my career and sodium bicarbonate is just the beginning.

If you think about it, sodium bicarbonte ingestion could hugely increase the risk of blackout in freedivers if it has the same effect on carbonic acid as it does for lactic acid. Research such as this is important for increasing scientific knowledge and for the safety of Freedivers who, as you said yourself, have already been using NaHCO3.

So if anyone wants to help improve awareness and safety in Freediving by being one of my subjects, or if you would just like some more information, I say again that I would love to hear from you!
From my experience, taking NaHCO3 or KHCO3 is similar to hyperventilating; i.e. reduces the bohr effect and causes delayed contractions & premature blackout. However, it probably would help people who have very little experience holding their breath, whose intrinsic [HCO3] is very low. In experienced divers, I think it would have a detrimental effect. Similarly, NaHCO3 may have a huge ergogenic effect for an inexperienced 400m runner, but a veteran with a high lactate threshold & high levels of natural buffers would not benefit much, and may even suffer from its use.

Eric Fattah
BC, Canada

The fact still remains that NaHCO3 is banned by most sports governing bodies but not by AIDA.
Do you not think that ingesting NaHCO3 might delay the urge to breathe by delaying the drop in pH due to CO2 build up? And if this were the case then surely the risk of blackout would be greater.
My understanding of the Bohr effect is that increased temperature or reduced pH have the effect of increasing O2 dissociation from haemoglobin. So wouldn't a delayed drop in pH due to NaHCO3 ingestion further increase the risk of blackout at higher O2 saturations?

In previous studies into the effect of sodium bicarbonate, effects have been found in some cases and not in others. The results seem to be dependant upon the intensity and duration of the exercise but not on the fitness of the individual. It is thought that ingestion of NaHCO3 might make only a small difference in elite athletes but that the difference is enough to make the difference between last or first place in an event such as the 800m sprint.

I am not saying that NaHCO3 will definitely improve or hinder freediving performance. That is what my study is trying to determine. But do you think it is wise to be using it in freediving?
Sodium Bicarbonate cannot be banned from any sporting event, because there is no way to differentiate between extrinsic bicarbonate and bicarbonate created by the kidneys. Doing a CO2 table for 60 minutes will result in a blood bicarbonate level far higher than you could ever get by ingesting NaHCO3, so how could you possibly detect it? Besides, 'banning' bicarbonate would be telling people that they cannot eat foods which contain bicarbonate precursors such as citrus fruits!! Suddenly orange juice is now banned as well!!

The IOC has no rules on electrolytes; the IOC does not ban substances which help, they ban substances which are harmful. Ginseng has been shown to increase performance, but the IOC does not ban it because it is not harmful. You are allowed to ingest anything that helps, so long as it is not harmful.

I would like to know which organization 'bans' NaHCO3, and how do they test for it. How can they differentiate between native bicarbonate and extrinsic bicarbonate?

Eric Fattah
BC, Canada
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Sorry, you're quite right Eric. My mistake!

They don't specifically ban NaHCO3 but they will not allow an athlete to participate if they have an unusually high urine pH. The athlete will be allowed to participate once they're urine pH has returned to normal, which rules out the possibility of gaining an ergogenic effect from sodium bicarbonate consumption.

I started this thread hoping to recruit subjects for my study but this is interesting!

Are you saying that it is safe and ethical for Freedivers to consume NaHCO3 prior to training or competition?
Let anyone take whatever substance they want. I explained this idea in my post in the thread 'drug abuse in freediving', reproduced here:

"Personally I wouldn't take illegal drugs, but I don't care if my opponents use illegal drugs. Let them take EPO, let them take steroids, beta blockers, let them take RSR13 or artificial oxygen carriers.

The diver who takes all of these things cannot even beat a penguin or a seal. Yet, the penguin and the seal were created without drugs, through natural adaptations.

The natural mechanism of adaptation is virtually flawless. Messing with natural adaptations will never allow you to reach your maximum potential.

Using illegal drugs may improve your performance in the short term, and you might beat Mr. 'Clean', but in the end, if Mr. Clean trains properly, and long enough, he will always beat the drug athlete.

I will give an example of this. If an athlete takes enough EPO, he eventually dies from too thick blood when his hematocrit goes over 60-65%.

However, Andean natives, through *natural* adaptations, have hematocrits of up to 80%, and they don't die from 'too thick blood', because their body has adjusted their fibrinogen and other viscosity agents.

This is just one example of how the athlete with the drug can never beat the human who has gone through natural adaptations.

Maybe the drug athlete can reach amazing performances in a very short time, but in the end he will be beaten.

Even with all the steroids invented, the strongest man in history is still Louis Cyr, who lifted 1968kg (4337lbs), in 1896, before the invention of anabolic steroids, using only natural adaptations as his weapon. He lifted 250kg (551lbs) with only one finger.

So, let athletes use drugs, because in the end they will never reach their maximum potential.

I investigated the potential for blood doping to improve Freediving performance and I think it is another area that requires proper experimental study.

I can't believe that you think people should be allowed to take whatever they want. Could you imagine how many talented athletes would die if there was a free for all on ergogenic substances? Sometimes the will to win is so great that people do things they regret later. They either have to live with the guilt of knowing that they won unfairly or on the other hand they could just die.

Rules and regulations are there to stop this sort of thing from happening because it has happened in the past.

Well done for not wanting to take illegal drugs yourself. That is very admirable.
What you forget is that 'banning' substances has almost no effect on the use of the substances, because (unfortunately) information is proliferated on how to 'beat' drug tests, and if what I have heard is correct, drug tests only catch 'stupid' cheaters, and the smart cheaters escape every time.

If a person tries to cheat, and dies, then he gets what he deserved. So let him cheat. Why should it be our job to 'save his life' when he is the one who was willing to risk his life to win?

Eric Fattah
BC, Canada
That is a good point Eric. So stupid people deserve to die. And so do cheaters. Well! My sunday school teacher will be turning in her grave!

Maybe the IOC should legalise all their banned substances so that all the stupid people and cheaters are discovered when they die in front of their families and fans!

And the world will be a much better place.

In the words of Gandalf the Grey "Some that live deserve death. And others that die deserve life. Can you give it to them? Do not be too eager to deal out death and judgement!"

Or something tothat effect.
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Unfortunately this thread seems to have steered away from my original intentions to find people interested in my research.
If anyone in the uk is within travelling distance from Luton (30 miles north of London) and is interested in being a subject, don't let the comments in this thread put you off.

I will clarify that the side effects from sodium bicarbonate consumption are normally due to inadequate water consumption which is actively encouraged as part of my methods.

None of my subjects so far have displayed any major symptoms or regretted taking part. They have been interested to see the difference in breath - hold times between their two seperate testing stages, although I cannot yet say if any effect is statistically significant or not.

I'd be glad to hear from you even if you just wish to know more or discuss further.


I completely agree with Eric Fattah on the matter of substance use by freedivers. Be my guests !

As far as sodium bicarbonate goes, wow ! You're supposed to EAT it ? If only I'd known ! I thought it ws a bit odd - it is very hard to light it. It keeps going out.

Paul Kotik
I'm amazed!

Another freediver with a complete disregard for the lives of other Freedivers! I wonder if all Freedivers feel this way?
And Eric is not "right"

He may be right in your opinion just as he is wrong in my opinion.

As I am conserned every research done on eney substance is a gain for all of us. It is one step closer to understanding chemical proceses in our bodys, and that is not important just for freediving.

About Erics statement:
If a person tries to cheat, and dies, then he gets what he deserved
I really hope this was not ment as it sounds!
It sounds like you almoust hate them.
I feel sorry for them for not realiseing what are they doing to the sport and themselfs!!

Why should it be our job to 'save his life' when he is the one who was willing to risk his life to win?
My oponion is that every life is WORTH saveing no matter what!!!

With researches like this we can spread the word about what substances or drugs do to our body , what are the risks and "or" benefits. I think we can save a few lives just doing that. Just makeing people aware what are they getting in to.


Freediveing is a dangerous sport it can be deadly we don't need durgs to make it more leathal.

On the other hand :
Sport is as safe (dangerous ) as you make it.
Thanks Zipy, I was beginning to despair.

You are right (in my opinion) that increasing awareness is of the greatest importance.

What are your views on banning substances?

If you have an opinion on this matter, I started a poll in the general freediving forum so go and vote!


The innumerable freedivers I've taken the time and trouble to keep alive when they blacked out may not concur with your proposition that I have a complete disregard for the lives of other freedivers.

I regard all adult freedivers as, well, adult freedivers. I have no interest in legislating their personal risk-reward calculations. If a freediver concludes he likes the payoffs in the risk-reward matrix for sodium bicarbonate suppositories, or Gitanes cigarettes, or riding a motorcycle to the competition, that is his business, not mine.

Paul Kotik

.... I mean, not to put too fine a point on it, but you DO realize that 99.99999% of the adult human beings on this planet would regard all of us as COMPLETELY INSANE to freedive at all !

They perceive the risks as a HUGE increment to those already inherent in simply being alive, and do not value the rewards.

We know better, right ?

Good illustration of how presumptuous it is to judge another person's risk-reward calculus.

Paul Kotik
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