One medical recommendation is applicable to almost every patients with lung disease: physical training. (standing side by side with don’t smoke!) When diagnosed with mild asthma years ago, Herbert Nitsch could be said to have taken the advice a little too seriously. Nowadays, the Austrian former airline pilot calls himself ‚the deepest man in the world‘, after breaking record after record over the last decade in the (rather terrifying) field of freediving.

Freediving is basically diving purely relying in breath-holding, without the use of additional breathing apparatus. Why are you not able to hold your breath very long before panicking and gasping for breath? Because breath-holding leads to a fall in blood oxygen levels as well as a steady rise in carbon dioxide. The fall in oxygen, when severe enough, can eventually lead to a blackout. The rise in carbon dioxide however normally  stimulates the breathing centre and triggers the urge to breathe before this occurs. But as with all sports, it’s a question of training.

In his keynote speech at a respiratory conference on Saturday, Nitsch explained how his average sized pair of lungs, with less than average function (due to his asthma) could be trained in order for him to hold his breath for more than 9 minutes in a static position as well as to eventually dive down to a breathtaking distance of 214m. Videos of deep blue seas, the excited nervousness of his safety team upon descent, encounters with sharks and one near fatal episode of decompression sickness (also known as ‚the bends‘) kept an audience of a couple of 100 chest physicians enthralled.

As well as techniques to increase lung capacity and to control the breathing reflex, divers have to deal with the pressure changes under water. Upon descent, the body is subjected to increasing pressures and the lungs are pretty much squeezed. Changes in the behaviour of gas according to pressure laws leads to an increased tissue absorption of nitrogen. When a diver ascends too quickly, the absorbed nitrogen is released back into the blood in the form of bubbles which can block up blood vessels causing everything from muscle pain and skin itching to damage to the nervous system, breathing failure and death.

The path into the world of extreme sports is fascinating. A world of risk, discipline, mental strength and seemingly insatiable ambition: after Nitsch spent 1 week in a coma, 1 month in a recompression chamber and months at a rehabilitation clinic learning to write again after a severe case of decompression sickness.