This incredible video shows the moment a world freediving champion jumped into the world’s second deepest underwater sink hole. The dramatic footage shows Guillame Néry standing at the edge before jumping in - all without scuba gear and simply holding his breath. And in the video he seemingly reaches the bottom of the 660ft (200 metes) hole before swimming back to the surface. French free diver jumped into Dean's Blue Hole in the Bahamas. Guillame Néry is seen at the edge before taking the plunge (shown). The hole is 660ft (200 metres) deep, although he doesn't go to the bottom. Free divers are able to hold their breath for more than 20 minutes . The video was filmed in 2010 by the Frenchman's girlfriend and fellow freediver Julie Gautier. It takes place at Dean’s Blue Hole in the Bahamas, the deepest so-called ‘blue hole’ in the world with an underwater entrance. In order to stay alive, the brain is constantly telling the body to breathe. If you don’t obey its primitive urges, carbon dioxide soon starts building up in the body, prompting an overwhelming desire to take a gulp of air. To fight that instinct, a competitive breath-holder has to work hard at expanding his lung capacity with a regular series of intensive breathing exercises. They practise ‘static apnoea’ once or twice a week, as well as ‘dynamic apnoea’ - holding breath while swimming - once in a while for fun, and also general fitness training. He also follows a diet high in fruit and vegetables, as well as broccoli, cauliflower and fish oil. However, Néry revealed a few years ago that he didn’t really reach the bottom of the hole - it’s just filmed that way for artistic reasons. But the video is still incredibly impressive, as he holds his breath for minutes on end. Freediving is a form of underwater diving where no scuba gear or breathing apparatus is used. To breathe for minutes, free divers go through sophisticated mind-body control techniques to push self-induced apnoea - the science of not breathing - to the limits. Some free divers can hold their breath for more than 20 minutes. Stig Severinsen, for example - nicknamed The Man Who Doesn't Breathe - is the holder of multiple records in diving using his 'State of Zen' technique to control his breathing. In October 2012, Mr Severinsen broke the record for the longest time breath held voluntarily by a male by spending 22 minutes with his head submerged in a pool in London. The dive took place in 2010 at Dean’s Blue Hole in the Bahamas (marked), the deepest so-called ‘blue hole’ in the world with an underwater entrance . The video was filmed back in 2010 by the French free diver’s girlfriend and fellow freediver Julie Gautier.It takes place at Dean’s Blue Hole in the Bahamas (shown), the deepest so-called ‘blue hole’ in the world with an underwater entrance .
French free diver  jumped into Dean's Blue Hole in the Bahamas . Guillame Néry is seen at the edge before taking the plunge . The hole is 660ft (200 metres) deep, although he doesn't go to the bottom . Free divers are able to hold their breath for more than 20 minutes .