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Doesn't the brain start to die after 10-15 minutes without oxygen? How could he possibly go that long without breathing without suffering any brain damage? I remember when David Blaine was going for the records, the biggest concern was that he would irreversibly and severely damage his brain.
On this topic, David Blaine's TED talk about holding his breath for 17 minutes is probably the most interesting TED talk there is. https://www.ted.com/talks/david_blaine_how_i_held_my_breath_...
On this topic, David Blaine's TED talk about holding his breath for 17 minutes is probably the most interesting TED talk there is. https://www.ted.com/talks/david_blaine_how_i_held_my_breath_...
Thanks for sharing - that was an incredible story. I find David Blaine fascinating because many of his magic tricks aren't tricks per se, he just does things that would be unthinkable for the average person. For instance he often takes a bite out of a wine glass and chews it up, and it seems like there must be some trick to it, except in one of his TV specials he goes to a dentist and reveals that his teeth are all w…
Ricky Gevais: "Sorry sorry David seriously, this isn't a trick. You're just sticking a needle through your fucking arm. What are you doing? That's fucking horrible. You're a maniac. That's the worst thing I've ever seen in my life."
Learning to control your body in idle circumstances is impressive in a meditative sense, but how people manage comparable durations while physically active is a different thing entirely.
Doesn't the brain start to die after 10-15 minutes without oxygen? How could he possibly go that long without breathing without suffering any brain damage? I remember when David Blaine was going for the records, the biggest concern was that he would irreversibly and severely damage his brain.
Of course, even with these preparations, freedivers have died and some have shown some damage.
Doesn't the brain start to die after 10-15 minutes without oxygen? How could he possibly go that long without breathing without suffering any brain damage? I remember when David Blaine was going for the records, the biggest concern was that he would irreversibly and severely damage his brain.
Yes, and the trick is to supersaturate your blood & tissues with vastly greater amounts of O2 than normal, and also to reduce your oxygen consumption rate. Of course, even with these preparations, freedivers have died and some have shown some damage.
What blows my mind is the guys that actually perform activities diving while holding their breathe for similarly long durations. Learning to control your body in idle circumstances is impressive in a meditative sense, but how people manage comparable durations while physically active is a different thing entirely.
Look for the "sea nomads", there have been articles about them recently, a recent (2016) research ( https://www.cell.com/cell/fulltext/S0092-8674(18)30386-6 ) suggests that their ability could be because they evolved a larger spleen (which helps with red blood cells).
I'm more impressed by spearos going down for several minutes, swimming hard, doing work, fighting a fish on a line and coming back up. I can manage 1:30 with that kind of activity but I have met folks who can go several minutes.
Doesn't the brain start to die after 10-15 minutes without oxygen? How could he possibly go that long without breathing without suffering any brain damage? I remember when David Blaine was going for the records, the biggest concern was that he would irreversibly and severely damage his brain.
Your blood cells buffer amount of O2 for use and CO2 ready for removal, which is how an untrained person is able to hold their breath and not die. When you stop breathing, consumption of O2 continues until CO2 builds up to a threshold point, triggering a desperate need to breathe (humans cannot actually detect O2 levels). If you try and hold your breath for too long, either the buildup of CO2 will cause the need to breathe, or lack of O2 will cause blackout and the autonomous nervous system to take over and resume normal breathing. While I am not a doctor, I don't see how it's possible to deprive your brain of enough O2 to damage it and not lose consciousness.
It's possible to train long breath holding in two ways: increasing O2 stores and increasing efficiency.
Hyperventilating can result in you purposefully purging extra CO2 and over oxygenating your blood. This will let you hold your breath for a very long time, I can comfortably go from a 30s hold to a 2m hold by pre-hyperventilating (see: Wim Hof Method). It also adds the risk of letting O2 levels drop before CO2 rises, causing blackout, which is basically one of the things that kills free divers. DO NOT DO THIS IN OR NEAR WATER, BLACKING OUT IN ANY AMOUNT OF WATER KILLS.
The other thing is that our systems that consume O2 can be made much much more efficient. Training probably helps, but there are some autonomous systems capable of reducing O2 consumption that all of us carry around. The mammalian diving reflex appears to automatically cut O2 consumption and limit max heart rate once your face is under water, for example.
tl:dr:
You carry extra O2, and you can increase how much on purpose. The rate you use O2 isn't fixed, and if you run out of O2 you black out and start breathing normally (which kills you if your underwater).
The hyperventilation thing is because your brain needs oxygen to live, but your impulse to breathe is driven by carbon dioxide saturation. When you hyperventilate, you get rid of a ton of carbon dioxide, and you can get into a situation where you don't have enough CO2 buildup to trigger the signal to breathe, but you have so little oxygen that your brain is dying.
Personally, not something I'd like to mess with.