Blood volume and body mass.

[perow1]

I am not sure if this is considered as common knowledge amongst freedivers or if there are posts on the subject already. Please post your thoughts on the subject.

I am wondering about body mass when it comes to freediving. Is it better to have a high BMI (not to the level of obesity) or a low? If body mass is kept at a fairly high level (perhaps mainly by muscle) the blood volume would be larger than if the same diver is kept lean.

Given a well trained dive response, wouldn´t this increased blood volume result in a larger storage capacity for O2? With a well trained dive reflex there will be more as blood for blood shift and vital parts of the body.

Is there a gain in storage capacity or is this effect cancelled out as a result of higher basal metabolism in the muscles even in a DR state? If body bulk is adjusted to be as large as possible without going past the critical point of affecting aquadynamics will the diver benefit from this.

As i mentioned earlier i do not know if there is info about this out there and I am not shure if you know what i mean, but please send me ypuir thoughts on this.

 

[efattah]

You have touched on a hypothesis which has been floating around for some time. I personally DO believe that bigger muscles (more blood) would benefit a diver, IF and only if the same diver has an extreme blood shift response.

However, this has yet to be proven.

 

[Murat]

Eric can you explain please what is extreme blod shift response?

 

[perow1]

Thank you Eric!
I suspected that this was something that people already touched with their minds. I beleive it is certain that with a 100% blood shift (if it is quick enough to occur so that the "extra" oxygen stored in the blood where no blood is not given the time to get depleted from 02 by the muscles) that it will be beneficial. I suppose that the real question is to what extent can the blood shift be trained and how quick? Maybe a "complete" dive response with maximum blood shift only renders in say 80% blood shift with still some blood left in the muscles. In this case the extra muscle will not be beneficial. Similary if the "complete" blood shift is 100% but takes time to occur the extra muscle will be bad since they will use up more oxygen than a slim diver would.

I guess it is hard to debate when nothing is proved. Perhaps one has to look at ones experience and on other divers to know what is optimal. One thing is clear to me and that is; if you get extra muscle yopu must do it in a way so they are suitded for diving.

 

[Aquagenic]

I posed a similiar question in this thread last year, but no major conclusions were drawn:

[ame="http://forums.deeperblue.net/showthread.php?p=454989#post454989"]Does Size Really Matter...[/ame]

This thread bats around the question a little more thoroughly:

http://forums.deeperblue.net/showthread.php?t=42486&highlight=bodybuilding

The previous thread has this informative post from E. Fattah about his views and research on muscles and freediving (assuming they haven't changed in the last year):

My research has led me to believe that when training muscles for freediving, you can take two different paths. Even marine mammals take one or the other.

- The first method is to develop almost entirely fast twitch muscles. This results in a huge supply of ATP and creatine, which generate energy without oxygen. This is the path taken by some seals who have over 70% fast twitch muscle fibers.

- The second method is to develop high myoglobin content in slow twitch muscles. This is the method taken by the extreme deep divers (elephant seals, most whales). This results in a huge oxygen storage in the muscle, but the muscle is not very strong, because as much as 30% of the muscle is composed of myoglobin bound in the slow twitch fibers. Such animals often have 90% slow twitch fibers, and often the O2 storage capacity of the muscle myoglobin is more than that of the entire lungs & blood.

Now, although the second method may lead to the greatest dives, it takes far longer than the first. But that's not all; no one really knows how to accomplish the second method. Myoglobin muscle biopsies are virtually impossible to get.

The first method (fast twitch) is well established. The method to build such muscle is extremely well researched. Various training programs such as Colgan's power program are readily available in print to accomplish it. I can say from experience that it works.

The second method is so mysterious and undeveloped that it takes guts to even spend time trying it. All the animals which have developed huge myoglobin exhale before they dive. So, the only thing we can infer is that practicing exhale dives may eventually lead to high myoglobin. It is quite certain that the muscles must be exercised in a deoxygenated state in order to build myoglobin, but that alone is not enough, because most athletes doing anaerobic training do deoxygenated their muscles (altitude training in particular), yet neither of these methods develops much myoglobin. Some studies have implied that exercising the muscle when the muscle is not receiving blood supply is the key to myoglobin growth. Thus, exercising the muscle in an extreme blood shifted state may be the key. During exhale dives, the blood shift is extreme. This also implies that no exercise on land could produce high myoglobin -- except, of course, if you tie a blood pressure 'cuff' around your upper thigh (which I have tried), but this method is very dangerous since you can burst blood vessels.

Emperor Penguins are born with low myoglobin content in their muscles. Their muscle myoglobin triples or quadruples in their first two years of life, as they dive continuously.

To finish, I'd say that the worst muscle for freediving is comprised of entirely slow twitch fibers, with low myoglobin content. These fibers consume huge amounts of oxygen. Exercising in the presence of oxygen (i.e. steady state cardio), produces such muscles, and it also increases the capillary density, providing more blood flow to the muscles. In seals, there is almost no capillary network to supply blood to the muscles. Blood is better used to supply the brain; the blood shift in these animals is so strong that during a dive there is almost no blood pumped to the muscles, so why bother with diverse capillary networks to deliver oxygenated blood? Let the muscle survive on its own stored energy, in creatine, ATP or myoglobin.

Yet, certain 'cardio' athletes such as Topi Lintukangas may appear to have great freediving performance. I think this is because their muscles have become very efficient in general. This does not mean that their muscle type(s) are ideal for freediving. The same athletes, spending their time producing freediving specific muscles, could probably dive twice as deep.


Eric Fattah
BC, Canada

As always thanks to Eric for his extremely knowledgable contribution to the freediving community. You the man Eric!

~James

 

[Sealdiver]

correct me if i'm wrong, but i've heard that if you have big muscles less blood is supplied to the heart and brain because more is needed in the muscles.

 

[efattah]

Sealdiver,

Possibly true under normal conditions, but in extreme blood shift, virtually no blood flows to the muscles, and almost all goes to the heart & brain.

 

[Sealdiver]

wouldnt your legs and arms go limp without adequet blood supply?

 

[Oligo]

Have you considered that maybe it is impossible to improve muscle myoglobin content in sufficient amounts to really benefit from it, because the myoglobin levels of human muscle and muscle of other animals is genetically set? No amount of training is going to push a human to have 10-fold more myoglobin in their muscle. I'm pretty sure the only way we could create a proper Homo Delphinus is with genetic engineering. The vanilla human is just too much of a prisoner of our adaptation to terrestrial life.

It would actually be pretty simple to up-regulate the expression of myoglobin genes so that we would have seal-like muscle full of myoglobin. That would be a good start.

Also, not nearly all blood flow is directed to the brain even when the diving reflex kicks in fully. This can be easily seen as any muscle activity lessens the time you can spend under water. If blood was directed solely to brain, Tom Sietas could do 10 minute constant weight dives.

 

[perow1]

The legs and arm will not go limp since your muscles use the energy stored in them aldready (such as ATP). Also the stored oxygen in myoglobin etc. is used to produce more ATP.

Things that are genetically set, as the case of myoglobin most probably is, is not restricted just because it is genetically set. A certain quality, such as body height (wich is of course a multigene quality) is set genetically. Though being genetically set there is much that can be done to affect this quality. The reason for human beeings growing taller each genereration (as of yet) is not an effect of natural selection. In the later decades food and living standards have started go get much better. The genetically set quality (height) is just given the right conditions to fully reach its potential.

The levels of myoglobin expressed in our muscles is most likely a harder connection genetically than height, but it is not said that it cannot be effected. Give the body the right condition to adjust and higher levels of myoglobin will be reached. We will NEVER reach the levels of deep diving whales, but it can definatly be pushed further. BUT how far can we push it? maybe it cannot be pushed so far that trying to increase your myoglobin levels outcompete the method of developing fast twitch muscles with lots and lots of ATP stored in them for a longer period of intense anaerobic work.

I would also like to add that Erics reasoning is very intelligent and interesting. I like his attitude, but i cannot actually beleive that he has tried to cut off the blood to his legs. Maybe one could overrcome the problem of bursting the vessels by wearing a "suit" wich tightly bings the whole leg and the arms leaving only the jonts free for movement That would not cause stress on one single point, but push all of the blood out of the region. But I guess that is not my kind of training.

Thank you eric and you others for your thoughts.

 

[ApneAnnelie]

As for the best distribution of musclefibers, freedivers want the benefit of both training the slow-twitch fibers (aerobic) which gives higher vo2-max, stronger heart/lower pulse, greater bloodvolume, e t c. But also the benfits from fast-twitch like a big supply of ATP and ability to work without oxygen.
Theroretically freediving itself, like DYN or CWT is an anaerobic activity, using mostly fast-twitch fibers. This although fast-twitch fibers are connected with high-power and explosive movements. Confusing!

Maybe the beginning of a dive is light enough to mainly stimulate slower-twitch muscle fibers, when it becomes too intense it will call on its fast-twitch IIA fibers, and last of all (for the highest intensity movements) it will recruit the fast-twitch IIB fibers? Type IIa is also a hybrid fiber, which is the easiest to adapt to new training.

We are genetically set with a certain ratio of fibers that can be adapted with training. Eric's research was very interesting - just like whales with 90% slow-twitch, some marathon runners have had up to 80% slow-twitch. Sprinters have up to 80% fast-twitch. I wonder who of them would be the best freediver!?

Another interesting test have shown that rats trained with hypoxia easier adapted their musclefibers from slow-twitch to fast-twitch.