WHO, WHAT, WHY?
The Magazine answers...
Illusionist David Blaine is attempting to break the world record for holding breath under water. But how do you hold your breath for nearly nine minutes?
1. Start inhaling and exhaling slowly
2. Breathe from deep within the diaphragm for last breath
3. As oxygen runs out blood diverted from hands to vital organs
4. At a critical level, could suffer latent hypoxia
He is spending seven days underwater in a "human aquarium" using only an air line to breathe, but that is not enough for illusionist David Blaine.
He plans to round off the stunt in New York by attempting to break the world record for holding breath under water - which currently stands at eight minutes, 58 seconds - while trying to escape from 150lb (68kg) of metal chains.
It is a task few professional freedivers think is achievable with the best of conditions, let alone after a week submerged in water, while trying to escape shackles. So how will he do it?
What Blaine is doing is called apnoea, which is the scientific term for breath-holding and literally means "without air". Because he is not descending through water at the same time, it is known as static apnoea.
To hold his breath for such a long time he will need to slow his heartbeat by relaxing, entering a meditative state. With a reduced heart rate the body consumes less oxygen, thereby prolonging the time Blaine can spend underwater.
He has also lost 50lbs (23kg) in weight to improve the efficiency with which his body uses oxygen.
To get the biggest breath he can for the challenge, he should start inhaling and exhaling slowly. This exercise rids the lungs of poor-quality air. For the final inhalation, he should begin slowly, breathing from deep within his diaphragm.
Some freediving experts get a final bit of air by using a technique called "packing". It involves gulping like a fish at the end of the breath to pack in even more oxygen. But it is a dangerous technique and very few people can do it properly, according to the British Freediving Association (BFA).
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As Blaine holds his breath his store of oxygen will reduce and the body will start diverting blood from his hands and feet to his vital organs.
Oxygen will fall to a critical level risking latent hypoxia - more commonly known as shallow water blackout - which is when a person loses consciousness. There are no warning signs, which is why static apnoea should always be done with a partner, says the BFA.
What Blaine does have which is extremely important for static apnoea is highly developed mind control.
"This discipline is a complete mind game," says BFA chairwoman, Emma Farrell. "It is the most psychological of all the freediving disciplines as you have to have a clear mind and stay calm while you are just lying there."
Secret to stunt?
The current record stands at eight minutes, 58 seconds, but freedivers have held their breath for up to 15 minutes by breathing in pure oxygen. That is how the BFA believes Blaine will pull off his stunt.
"It is simply not possible for him to breathe in air and hold his breath for that long while escaping from chains," says Ms Farrell.
"Static apnoea is all about getting yourself into a deep state of meditation which you can't do while trying to escape from chains, he will have adrenalin pumping through his body.
"To pull off the stunt I think he will actually breathe in pure oxygen through his air line, which will help him hold his breath for longer."
Judges from the International Association for the Development of Apnoea (AIDA) would have to attend Blaine's attempt for any record set to be officially recognised.
Their attendance has not been mentioned by the illusionist, probably because under the AIDA's rules they would have to spend at least two hours with him before his record attempt to make sure he does not breathe in any pure oxygen.
The BFA is sceptical about Blaine's stunt and also concerned that it will encourage people to try and hold their breath underwater without training.
"We have tried hard to change the image of freediving," says Ms Farrell. "People tend to think it's an extreme sport and it's not. Freediving is very safe if you do it properly.
"By turning it into a stunt, David Blaine is sending out the wrong message about freediving and damaging its image."
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I think he will not be able to complete this feat. I can hold my breath for 7 minutes. I am a trained diver from Bogra, Bangladesh - I used to dive a lot working with dolphins. This seems an impossible task, especially trying to get out of chains at the same time.
Kazi Rahkman, Belfast
This is just another typical Blaine ego trip. In America they are big on such stunts but as previously seen Londoners mock the idiotic. In the interests of self-promotion Blaine spent several weeks in a box without food, in Africa this is called a famine and not something to celebrate. He froze himself in a block of ice, a common activity for the homeless of the world. And in a remarkable feat of endurance he stood still on a pole. Try doing that while wearing a bearskin hat, heavy uniform and having tourists prod and take photos and then we might be impressed. If Blaine really wants to impress the public he should learn to string a sentence together when being interviewed on television.
John Nevill, Dagenham, UK
David Blaine is an illusionist, a magician. That means that all his stunts, whether holding his breath or living in a huge ice-cube or being buried underground, are illusions. Like any good trick, the audience should be amazed and mystified - and would be disappointed if they knew the method behind the trick! So stop taking it seriously and looking for scientic methods to what are just magic tricks!
I hadn't even heard of freediving before and I'm not such an unthinking cretin that the Blaine stunt will make me think I can hold my breath for ages. The BFA are making a fuss over nothing.
Keith, London, UK
It's funny how different people perceive David Blaine. Some think he's a joke, as in the UK. Others think he's great entertainment. And still others think he's accomplishing amazing mind-over-matter endurance feats which can further be explored scientifically. The late Christopher Reeve saw him as a hero who wills his body to obey his mind. I concur with this viewpoint. Blaine, for whatever reasons, is pushing the boundaries to learn of a human being's capacity to go higher and higher. He deserves to stand tall with the great ones of the past who, despite misunderstanding and ridicule, proved that man is more than just merely flesh, but a being with greater capabilities of mind and spirit as well as body.
Just spending a week immersed in water is risking severe skin damage - the man who holds the record for time spent submerged spent longer in hospital afterwards having skin grafts. Think of wrinkly skin in the bath only much, much worse.
Maybe they will play his voice into some waterproof earphones which will then send him into a deep meditation / coma. I know he has that effect on me!
H Trigg, Swindon
David Blaine is an illusionist, as the name implies this stunt is not all it seems, it is an illusion hence no officials confirming his record attempt The sooner he goes back to magic instead of stupid publicity stunts the better!
Graham Ingleby, Redhill, UK
Why give so much publicity to this man? He is obviously an idiot who will do anything to get his name in the news. What is the point of it all?
John Larkin, Madrid, Spain
get a job david, not impressed by this, the card tricks were good but this endurance thing is just boring. people in parts of the world are doing more enduring feats and not for entertainment it's how they live. instead of sitting in a big bubble why dont you tell the world about somthing more worthwhile maybe people will listen
Ben Scarborough, United Kingdom
Sorry, can't comment right now, I'm on my way out the door to visit Blaine and drive some golf balls at his perspex sphere...
chris mccombs, Cincinnati, US
David Blaine gets more irritating every time he pulls one of his stunts. To be honest it's getting tiresome. If what the Freediving experts say is true, then he's being very irresponsible just for the sake of appearing more mysterious and enigmatic. Give it up, David! We're running out of interest and patience!
Edelle McMahon, Belfast
Blaine shouldn't be allowed to belittle the current and past holders of the geniune record with this stunt.
I, for one, am proud of the reaction his last exploits in London garnered him.
Sam, London, UK
I used to be able to hold my breath for over two and a half minutes. My friends were sceptical so I decided to show them how I did it in a small swimming pool. Half way through my demonstration they got bored and wandered off. I don't remember much beyond the two minute mark - blacking out and apparently sinking to the bottom face up. Luckily someone pulled me out and I found myself on the side of the pool. My stopwatch had just passed three and a quarter minutes. To anyone thinking of testing their breath holding skills I'd recommend just one thing. Do it above water and with someone paying attention. You can just as easily drown in the bath as a swimming pool - or a giant goldfish bowl in New York.
Dominic Brennan, Weybridge
Personally speaking I find him and his stunts irritating and irrelevent. It's just a shame he's not doing it in London then we could go and throw eggs again!
Matt, Hazlemere/ Bucks
Please stop adding to Blaine's ridiculous hype!
Emma Leah, Birmingham, UK
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