apnea kills brain cells?

[growingupninja]

Old thread but relevant topic, not fully discussed.
William Truebridge lost his sense of taste permanently after blacking out diving around 200 feet. I am not an expert but there arent many things that could cause that during a dive but one of them is brain damage.
Im not saying that is proof that apnea causes brain damage, but blacking out very well may.

re: William may choose to speak for himself but friends of mine who have dove with him have told me the journalists covering his story for 60 minutes got it wrong--the loss of taste is from ciguatera ('cig'), a neurological toxin that typically accumulates over time from eating a lot of large, old tropical reef fish (apex predators). It had nothing to do with BO.

 

[Kars]

Where does this ciguatera come from? What are they? It almost sounds like he lost the appetite for cigarettes ;-)

 

[Gizzo]

I have been a very deep apnea diver, arrived 6th in the national spearfishing competition 1973 and 2nd with my team a pair of years later. I was used to keep groupers at 30-35 meters depth (see the picture of my profile). In 1978 I had a black out with some hours of coma. Now I am 65 years old and a I am a good scientist with more than one hundred published papers. I think that training brain cells to operate effectively with low oxygen will increase their capacity of working with normal oxygen partial pressure.

 

[HydroApprentice]

This is an interesting aspect, which hasn't been discussed much... I'd be curious to hear what's known in that direction!

 

[Gizzo]

What makes the difference between a good and a bad apneist is the capacity to make effective work in depth. It is typical of trained sportsman like swimmers, waterpolo players, rowing sportsmen, etc. to have good apnea time, but when they try spearfishing they are very often incapable. They see a fish, plan something in surface and when they go in depth make wrong things. A trained apneist develop the capacity of being very effective in the tens of seconds he is in the bottom: his brain cells work very well with low oxygen pressure.........This is my opinion.

 

[Kero]

I've been told by Will himself, that he lost his sense of taste during preparing for a World Record. His sinuses were blocked but he really wanted to dive and used all kinds of nasal sprays you are offered in Dahab. Also, he said, he didn't loose it completely. Like, he can still taste and smell different aromas, but he can't tell salty water and fresh water apart for example.
But as already mentionend, let's wait for a reply of Will himself on this topic

 

[subunit]

My brother, who is a fan of extreme SCUBA diving, has this idea in his head that freediving = brain damage because he has read or heard somewhere that Asian freedivers who do so as a matter of career (pearl divers or whatever) have been found to suffer from brain damage in relation to longterm freediving. I have repeatedly asked him for a reference as to where he heard this, and have tried explaining to him that if that were so it would be due to longterm blackout problems or neurological DCS, which he would be just as prone to get himself in the right circumstances. He isn't buying it, and his notion keeps resurfacing inspite of the fact that he himself has made numerous freedives to atleast 20m. It really bugs the heck out of me, because he is crapping on my sport, so I wanted to dig up some references to non-blackout related freediving brain damage.

....i know this post is more then 10 years old, but its still a very intresting topic.
and eventually 2 years ago, some scientists did a study that refers exactly to your question.

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0105006

 

[J Campbell]

Doing sport diving/spearing where you surface fully oxygenated is probably not ever going to hurt you. But competitive divers routinely deplete their oxygen to the point of blackout. Isn't the whole point of a static competition to see if you can push yourself right up to the edge of blackout - ie not enough oxygen to the brain? I wonder if over time that this may harm you.

 

[subunit]

Doing sport diving/spearing where you surface fully oxygenated is probably not ever going to hurt you. But competitive divers routinely deplete their oxygen to the point of blackout. Isn't the whole point of a static competition to see if you can push yourself right up to the edge of blackout - ie not enough oxygen to the brain? I wonder if over time that this may harm you.

....i dont have prove to your theory, but i do agree that pushing oneself to the edge, or further, of a blackout by
breathhold will do your brain no good. so does too much beer on a friday night probably as well....
but thats not what the study is about. have you read the study ?

 

[J Campbell]

....i dont have prove to your theory, but i do agree that pushing oneself to the edge, or further, of a blackout by
breathhold will do your brain no good. so does too much beer on a friday night probably as well....
but thats not what the study is about. have you read the study ?

I skimmed the study - here is the conclusion at the end:

"In conclusion, our results suggest that long-term commercial breath-hold diving can cause brain damages even if neurological DCI events were transient or have not occurred in divers."

Also, I don't recommend "drinking to much beer".

 

[Pinniped72]

So long term it can damage the brain, I am still more worried about the pressures of living a rushed, busy life style, doing a job to pay the bills were the employers aim seems to be, to drain the very last drop of enthusiasm and passion for life from your shrivelled decaying corpse, damaging my brain and shredding my soul................... I think i'll carry on diving and not worry about it too much

 

[subunit]

So long term it can damage the brain, I am still more worried about the pressures of living a rushed, busy life style, doing a job to pay the bills were the employers aim seems to be, to drain the very last drop of enthusiasm and passion for life from your shrivelled decaying corpse, damaging my brain and shredding my soul................... I think i'll carry on diving and not worry about it too much

....couldnt have said it better....!
nonetheless the study shows some intresting results.
and apparently it have been the first study on that particular topic.
it lookes like that dci events, even neurological, are not only related to extremely deep freediving/spearfishing.

QOUTE ."Our survey of commercial breath-hold divers (Ama) in Japan have shown that repetitive, working breath-hold dives can induce neurological DCI. Based on the reported symptoms and neuro-radiological findings, brain lesions were particularly prominent in this group."QUOTE

but then the study does not conclude that brain damage are only caused by dci events of a diver.

QUOTE :"It was shown that incidence of brain lesions increases with diving experience, suggesting that diving could have a cumulative effect on the brain even without a history of symptomatic injuries:"QOUTE

in general i am very critical about scientific studys and their results ( particular marine-biologists),
but sometimes they are the only way to get at least some good information on topics that we wont get otherwise.
would i like to get my brain scanned to see any damage ? hehe....glad the others did....

are there anybody here in the forum that had or know of someone that had any dci-event through deep or
intense repetitive freedive-spearfishing ? would be intrested to hear about....

 

[J Campbell]

Also, the study is looking at "neuro-radiological" changes and brain lesions - but does this translate into any real loss to the person? I mean, does it make them "dumber" or shorten their life or otherwise diminish them in some way? These Ama divers are living as long as the rest of us - into their 80's. I doubt that freediving does any meaningful damage.

 

[subunit]

Also, the study is looking at "neuro-radiological" changes and brain lesions - but does this translate into any real loss to the person? I mean, does it make them "dumber" or shorten their life or otherwise diminish them in some way? These Ama divers are living as long as the rest of us - into their 80's.

..i really cant say, since i did not saw any reference in the study. they only reported about the damages they found through their study, but did not say how these damages actually harm or restrict the tested person.

QOUTE :"I doubt that freediving does any meaningful damage."QOUTE
but contrary to you, i do believe that freediving can do meaningful damage to humans.
probably just to those that practicing freediving/spearfishing to an extremer level as the average joe.

 

[growingupninja]

I would take this study with a huge grain of salt. All the deeper divers studied were 'assisted' (meaning variable weight with somebody else pulling up the weight) and diving 5+ hours a day like that. This is NOT how sport spearing and freediving is performed, even at elite levels, and the DCI markers were far more prevalent in the 'assisted' divers.

From the weight they were using to go down (20kg), it would mean they were going down at VERY fast, probably 3M/sec at least. For reference, your typical freediving school trains divers to go up and down 1M/sec (and many guys come up slower, I do). The nature of variable also means they were likely weighted to be just neutral on the bottom which means they were coming up very fast with little resistance--faster than a typical constant weight freediver or spearo. 30 drops per hour. For average village guys who do this sort of thing all the time, 1:30 dive time (with nearly all of that at target depth since you're effortlessly rocketing down and up at 3x the speed of a CWT diver) and 30 secs at the surface would be cake, but only doable with a team hauling up your weight and catch.

My comment is not to say that you can't get DCI from spearing or freediving or that it is 100% safe, but they studied a population that dives in a way that the modern freediving and spearing community already knows lead to problems: Using surface muscle to shave down surface interval and minimize the commute to/from depth which in turn extends bottom time to beyond the diver's natural ability, and ascending supernaturally fast.

 

[subunit]

....as i also wrote before, i agree that this study is not representive for the average joe-spearo.
but i do know some people who do or did freedive-spearfishing on a more intense level,
some deep diving, and some rather shallow but with a very high level of repetition.
i had times with a lot of intense spearing and was always very much concerned with facing
the actual daily dangers, wich are there plentyful enough.
but never had a thought that there could be any longterm danger in terms of braindamage.
first thought about it some years back, when a good friend of mine who knows nothing
about any diving, ask me what it is i am doing daylong out in the sea.
i simply told him that i hold my breath and dive down to catch fish.
he replied that he hope my brain dont get damaged when i get older, simply because withholding oxygen
from your brain over and over again cant be healthy.
i still agree very much with what pinniped72 wrote earlier in this thread, but do believe that this study
shows intresting results, and believe further studys, wich may focus on different persons then the ama-divers,
and with a wider approach would be intresting to see.
until i keep on diving and drinking, and dont worry about it too much....

 

[cdavis]

Comparing microwaved apples and frozen oranges. Anybody who relates that study to blackout damaging brain cells is so far off base its hard to comment. Damage from DCS is what the study looked at; it had nothing to do with BO or breath holding in general. Ninja's comments show how far from normal diving amas can be. Personally, I'm not surprised that freedivers spending enough time under water to make a career living showed signs of DCS, very logical. Those using variable techniques would be even more likely. Comparing that to normal freedivers and BO simply does not compute.

Is there anything else that takes a quantifiable look at BO and brain damage?

 

[MarcinB]

Here's the list of all published research on this matter (not only on BO, breath-hold in general):

Ridgway L et al. Apnea diving: long-term neurocognitive sequelae of repeated hypoxemia. Clin Neuropsychol 2006;20(1):160-76.

Gren M et al. Blood biomarkers indicate mild neuroaxonal injury and increased amyloid beta production after transient hypoxia during breath-hold diving. Brain Inj 2016;30(10):1226-30.

Mats H. et al. Hypoxic syncope in a competitive breath-hold diver with elevation of the brain damage marker S100B. Aviat Space Environ Med 2009;80(12):1066-8.

Andersson J. et al. Increased serum levels of the brain damage marker S100B after apnea in trained breath-hold divers: a study including respiratory and cardiovascular observations. 2009 J Appl Physiol 107:809-815.

Patricia Ratmanova1 et al. Prolonged dry apnoea: effects on brain activity and physiological functions in breath‑hold divers and non‑divers. Eur J Appl Physiol 2016;116(7):1367-77.

Kjeld T et al. Release of erythropoietin and neuron-specific enolase after breath holding in competing free divers. Scand J Med Sci Sports 2015;25(3):e253-7.

Potkin R. et al. Brain function imaging in asymptomatic elite breath-hold divers. In: Lindholm P, Pollock NW, Lundgren CEG, eds. Breath-hold diving. Proceedings of the Undersea and Hyperbaric Medical Society/Divers Alert Network 2006 June 20-21 Workshop. Durham, NC: Divers Alert Network; 2006.

 

[subunit]

Here's the list of all published research on this matter (not only on BO, breath-hold in general):

Ridgway L et al. Apnea diving: long-term neurocognitive sequelae of repeated hypoxemia. Clin Neuropsychol 2006;20(1):160-76.

Gren M et al. Blood biomarkers indicate mild neuroaxonal injury and increased amyloid beta production after transient hypoxia during breath-hold diving. Brain Inj 2016;30(10):1226-30.

Mats H. et al. Hypoxic syncope in a competitive breath-hold diver with elevation of the brain damage marker S100B. Aviat Space Environ Med 2009;80(12):1066-8.

Andersson J. et al. Increased serum levels of the brain damage marker S100B after apnea in trained breath-hold divers: a study including respiratory and cardiovascular observations. 2009 J Appl Physiol 107:809-815.

Patricia Ratmanova1 et al. Prolonged dry apnoea: effects on brain activity and physiological functions in breath‑hold divers and non‑divers. Eur J Appl Physiol 2016;116(7):1367-77.

Kjeld T et al. Release of erythropoietin and neuron-specific enolase after breath holding in competing free divers. Scand J Med Sci Sports 2015;25(3):e253-7.

....wow, that is a lot of information. Well researched. Do you know if there is any of those studys available to read
in full length online ? ..any link ?

 

[subunit]

Is there anything else that takes a quantifiable look at BO and brain damage?

....would be intresting to read something about that topic.
it seems logic that there are brain damages possible by pushing oneself over and over again close to,
or even into a blackout....
thats one of the reasons i never got into boxing....