• Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 44,280+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 516,210+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,441+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

Maximum static apnea possible (EVER!)

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.

MattB

New Member
Sep 1, 2010
30
8
0
This is from the book "Perfection Point" by John Brenkus. He is the creator of sports science on ESPN and he wrote this book about finding the limits of human athletic ability. He consults many experts and athletes and uses a lot of accurate math to make his prediction. This on the breath holding section. It predicts the maximum static apnea someone could ever do. I just thought I'd share this section with you. No copyright infringment intended. I don't own this just using this for entertainment and educational purposes.
"Location: The Jordan Rift Valley
Date: December year 2672
Our ideal athlete is six feet six inches tall and weighs 180 pounds. He was born and raised in La Rinconda, a mining village of over seven thousand people in southern Peru that has been in existence for 50 years. At over 16,700 feet, only 800 feet shy of North Base Camp at Mt. Everest, it's the highest permanently inhabited town in the world. The athlete who doesn't experience the symptoms of hypoxia until his brain oxygen falls below 93 percent. He won't black out untill it drops below 85 percent.
His lung capacity is 13 liters. With packing, he can squeeze in another 1.2 liters without risking a potentially lethal lung injury. Because of residual volume, only 90 percent of it is usable, and only 21 percent is oxygen, so the total available oxygen in his lungs is 2.7 liters.
Someone living at an altitude near sea level has a blood oxygen-carrying capacity of about 20 ml of oxygen per 100 ml of blood (20ml/100 ml). But because of the greatly boosted red cell density in our ideal athlete's thickened blood, there is enough hemoglobin to carry 35 ml/ 100 ml. When at home in La Rinconada, he never gets even close to full capacity, but he will during his static apnea performance. It's going to be held at the Dead Sea, just east of Ein Gedi, Israel. At nearly 18,000 feet lower than his home elevation, the partial pressure of oxygen will be twice what it is at La Rinconada. For him it will be like breathing in a hyperbaric chamber, but in full compliance with AIDA rules because he's taking in only normal, ambient air.
The competition is held in a pool on the beach because the waters of the Dead Sea are not the kind you want to put your face in. For the first three minutes of the hold, oxygen will be absorbed into his blood at a rate of 1200 ml per minute. It's far more than he needs to keep his brain oxygen levels at 100 percent but there's no way for him to slow it down.
After three minutes, the absorption rate begins to drop. Sometime into the sixth minute it's at only 200 ml/min and, at the rate, 100 percent brain oxygen saturation can no longer be maintained. Even as an uncomfortable pressure in his chest begins to gnaw at him, a survival mechanism triggers his heart to beat faster and get more blood flowing to the brain. This doesn't put more oxygen into the blood; it just gets more blood to the brain.
The blood flow continues to increase, but after another four minutes, it's hit twice it's normal rate and can't get any faster. Oxygen absorption from the lungs into the blood is down to 50 ml/min, and his brain starts taking emergency measure to keep itself alive. Blood flow to the extremities decreases in an effort to shunt more to the brain.
Despite these measures, oxygen saturation in the brain starts dropping. There simply isn't enough oxygen available to keep the level at 100 percent. In another two minutes it's down to 93 percent, and the athlete begins experiencing the symptoms of hypoxia.
He feels himself swaying, rotating, ass though swept by a current. The touch of a hand on his shoulder momentarily orients him and he realizes he's perfectly still, not moving at all. A small voice arrives, as if from a great distance, and tells him the elapsed time. He raises a finger in the air to let the coach know he's alright, and that small act grounds him once again.
But it's short-lived. Most of the air in his lungs has now turned into CO2 and his body, in a vain attempt to get him to seek fresh air, is assaulting his chest. The pressure has turned into pain; the gnawing has taken on the hint of suffocation.
The flow of oxygen from his lungs into his blood continues to slow, and the levels in his brain drop even further. After several more 15-second signals and responses, he begins hallucinating, his inner vision alternately brightening and darkening. He barely understands the time calls anymore, and his signals are largely based on reflex. Shadows swim before his closed eyes and he has to fight to remember who he is and why he's not breathing.
Something lands on his shoulder; almost too late he remembers what it is and raises a finger. The hesitation puts the coach on alert. Fifteen seconds later it happens again, but again the athlete got the finger up in time. Or did he? He raises it again just in case, and now the coach is worried: is he really responding purposefully or is he just on autopilot? He's going to shorten the interval to ten seconds.
The athlete's lung-to-blood absorption rate is down to 8 ml/min and his brain O2 level is at 86 percent. His chest is screaming, and there's a volcanic eruption inside trying to blow him apart. Poised at the very edge of blacking out, he feels a touch on his shoulder but it's more than a touch this time; it's a pain. The coach is squeezing him, hard, and he won't let go.
With everything left of his mental faculties the athlete forces himself to concentrate. He opens his mouth and exhales, a cloud of carbon dioxide bubbles boiling to the surface. He keeps his head in the water- no sense surfacing and stopping the clock if all he's going to do is exhale- and when the last of the gas is expelled he raises his head, tears off his goggles and nose clip, makes of circle of his thumb and forefinger and says 'I'm OK!' The judge acknowledges with a nod, and that makes the time official.
The athlete gasps, inhaling mightily. The putrid air of the Dead Sea is like the purest nectar he's ever tasted.
It's the first breath he's drawn in fourteen minutes and forty-seven seconds."


There you have it, the maximum static apnea possible by humans. I hope you guys enjoy this, it took forever to type this! :)
Again no copyrights or anything like that intended.
 
The athlete who doesn't experience the symptoms of hypoxia until his brain oxygen falls below 93 percent. He won't black out untill it drops below 85 percent.

Sometime into the sixth minute... a survival mechanism triggers his heart to beat faster and get more blood flowing to the brain....


Interesting. Wonder where he got those numbers/facts from?
 
Those numbers are that of the absolute most ideal breath holder the human race could ever produce. He does tons of research. The breath holding section was a chapter of 15 or so pages of information on all the different aspects of static apnea. The part I shared was the end where he puts all his research into a scenario.
By the way, congrats!
 
Sounds like he might have got the wrong end of the stick wrt certain aspects. The ideal STA athlete could pack a lot more than 1.2l too. But good to see freediving being thought about in this way.

Thanks!
 
The author of that piece is a good friend.

Kind of a downer that my name appears in a book for the first time in my life, the editor gives me a chapter of my own and the unauthorized quote of it on my favorite website leaves me out.

Dave, the writer had many masters and had to please medical experts that you would disagree with. The 'excerpt' is very much out of context.
 
Anybody know whether cerebral O2 saturation is much different from O2 sat as typically measured during a breathhold?

I can understand having to please a bunch of different people, as happens in publishing, but some of that stuff is so far off base you have to wonder where they got their facts from. I thought bradycardia was a pretty well known and non-contentious bit of the MDR. Bizarre statement about RV being 'unusable' too. He's assuming RV contains 0% O2.

What is the context - are they speculating about big physiological changes to the species several hundred years in the future?
 
I swear I saw a post from you about oximeters... ahh here it is, in this thread...which talks about the very thing! Did you read it all? :t Or maybe I'm misunderstanding the question...

There's a significant difference, MDR/vasoconstriction plays havoc with normal SaO2 analysis (oximeters), even good ones, seeing as I learned this mostly off the forum from trux I'll give him the due credit ;):
The level of saturation is namely not equal in all body. There are gradients. If you have an area with restricted circulation, the tissue there oxygenates slower and blood desaturates of course faster (that's why it works so well for us), hence there are lower saturation values than in the core. You would need to measure on arteries (and closer to the heart would be better), to avoid that effect.

To be accurate - take arterial blood throughout the hold and test it. Anyone done that?:blackeye

In several hundred years we'll have nanorobots taking care of all our physical needs and giving us oxygen regardless of if we breath or not...
 
Last edited:
Yeah I imagine there's a gradient, just wondering if it's that steep (50% periphery vs 85% core). Earlobe sensors shouldn't be too far wrong?

If there can be a gradient like that due to vasoconstriction, then there must be no vasoconstriction at all in the first 3 or so minutes of, say, Wal's static, because the fingertip oximeter still reads 98% up to that point. Not out of the question I suppose but it's making 85% sound a bit high.

In other news: I've fashioned a genuine arterial oximeter out of a ballpoint pen, a rubber glove, some tubing, a normal fingertip oximeter and a bit of sticky tape. Volunteers?
 
Last edited:
Well, I did not react, because I though it was a quote from some sci-fi book, which did not pretend any real scientific background, but if it is the contrary, then I have to agree very much with Dave that it is full of factual errors.

1) A trained apneist will blackout at SaO2 around 50%. The cerebral arterial saturation cannot be really higher than saturation measured on other arteries. Good oximeter measuring really arterial saturation and not that of the venous blood will get the saturation pretty well. Some more details about the saturation levels at breath-hold divers can be found for example here: http://diss.kib.ki.se/2002/91-7349-314-7/thesis.pdf

2) Heart rate does not raise but drops during a breath-hold. Of course, there may be variations, and at the beginning there may be higher rate due to stress, packing, hyperventilation, etc, but once you put the face under water the HR drops, and continues dropping. Again there are some stats and graphs in the same study linked above, and it can be found in many other scientific studies on that topic

3) The nonsense with the unused residual volume stroke me immediately too. Of course, the air in RV is used. However, the entire calculation is wrong. The content of O2 in lungs is not 21%. First of all it drops to ~20% due to increased level of water vapor. Second, there is increased level of CO2 in lungs (even with extreme hyperventilation). Some more on this topic can be found again in the same study, and in the following thread, where I also posted the this image:

http://forums.deeperblue.com/freediving-science/77624-hyperventilation.html

hyperventilation.gif

4) Top freedivers can pack much more than 1.2l. For example in the following study 6 freedivers packed in average to 1.59 liter +/-0.57l (which means the maximum of 2.16 liters of packed air). And those were not the top packing freedivers. If they measured Sietas or Mifsud, and couple of others, it would be even more. Who knows where the limits will be in ~660 years.

http://www.ncbi.nlm.nih.gov/pubmed/16525813?dopt=Abstract

As for the high hemoglobin contributing to the record - hemoglobin has also the disadvantage of thickening the blood, and requiring stronger heart output to assure the circulation, hence the advantage is somehow reduced. Myoglobin would be more useful. However, better than high hematocrit and easier to reach would be instant and strong diving response with solid vasoconstriction and bradycardia - I think that would allow for longer times.
 
Last edited:
"What is the context - are they speculating about big physiological changes to the species several hundred years in the future?"

Close. It started out as speculation of future world records in many sports. No rules and written for sports fans.
 
Mr Mullins i accept your challange :) bring on the ball point pen thingy.... as long as you pay for my flight to NZ you got yourself a guinnia pig. hahahaha

DD
 
Raise ya!... look what I found in the back cupboard this morning! rofl Yes - really! Must be a relic from an old tenant :blackeye

bloods.jpg
 
It was an interesting piece of work (predicting 14 minutes), except that it is, in my opinion at least, completely wrong.

There are two secrets to sci-fi type breath-holds:
1. Hypothermia (controlled)
2. Vagal stimulation

First of all, you can attack the problem from the ground up. The minimum metabolic rate for mammals has been calculated, below which life can't be sustained. If you take a seven foot tall person with enormous lungs and packing, with high quality blood, and apply the minimum metabolic rate (which occurs around 15C body temperature), the result is a breath hold of over 6 hours without brain damage. At this body temperature the person would not be conscious during the apnea, but they would be totally fine at the end.

If you insist on consciousness, the degree of hypothermia needs to be reduced to around 34C, and you would need to use methods to block the shivering response.

When the vagus nerve is stimulated (for example with the contraction blocking method I describe in other threads), the heart rate can be reduced to 15 beats per minute or perhaps way lower, with corresponding drops in metabolic rate.

With a sufficiently tall person, having fasted for a long time to reduce metabolic rate in general, followed by a brief carb loading, and mild hypothermia with vagal stimulation, over 30 minutes would be possible with consciousness, although it is hypothermic consciousness with slurred speech capability. Yogis have spoken of 30min+ breath holds for hundreds of years, which doesn't surprise me at all.
 
No heart beat and freezing cold? Eric, I do believe you just described a vampire!

Given the popularity of the undead of late, I can suddenly see all kinds of PR opportunities for apneists :D
 
Last edited:
Yeah, doesn't taste quite like the real thing, does it (draws curtains fully closed).
 
"Discussing the limits of static apnoea duration with elite free divers revealed that they expect the limit to be extended to around 15 minutes before record setting will level off. It seems likely that the addition of some O2 stores, a further lowering of metabolic rate below resting levels and anaerobic metabolism in vasoconstricted areas could prolong apnoeas even further."

(from Predicting performance in competitive apnoea diving. Part I: static apnoea. By Erika Schagatay)

You can read the whole document at http://www.freediving.biz/education/staticscience.pdf
 
  • Like
Reactions: PVJensen
DeeperBlue.com - The Worlds Largest Community Dedicated To Freediving, Scuba Diving and Spearfishing

ABOUT US

ISSN 1469-865X | Copyright © 1996 - 2024 deeperblue.net limited.

DeeperBlue.com is the World's Largest Community dedicated to Freediving, Scuba Diving, Ocean Advocacy and Diving Travel.

We've been dedicated to bringing you the freshest news, features and discussions from around the underwater world since 1996.

ADVERT