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Very impressive but it is the WR after oxygen breathing not air breathing. It makes a big difference, given some time to prepare (ie hyperventilate to wash-out the carbon dioxide and fill the lungs with oxygen) most healthy people will manage breath holds between 5 - 10 minutes.

The reason you can hold your breath longer with oxygen in the lungs is that despite the fact that most of our air hunger is due to the increase in carbon dioxide in the blood, reduction of the oxygen levels - as in a normal breath hold - potentiates the carbon dioxide effect. When the lungs are filled with oxygen the air hunger from the high carbon dioxide levels will not be so strong.

The first WR breath hold using oxygen was set by a US college student who held his breath for ca 19 1/2 minutes. Calculations showed that he had been very close to his absolute theoretical maximum.

What is it that sets the limit?

When you hold your breath with air in the lungs it is the amount of oxygen you have onboard, and it must be enough to keep you from losing consciousness. So, the lower metabolic demands (complete rest) and the larger lungs you have the longer you can hold your breath.

However, when holding ones breath with lungs filled with oxygen it is the lung volume (not the oxygen stores) that sets the limit. A steady amount of oxygen is removed from the lungs to the body, but due to our blood chemistry the same amount of carbon dioxide is not put back into the lungs to replace the lost volume. So, the lungs will continually shrink until their volume cannot be reduced more. (In worst case the volume will be replaced by fluid - lung oedema! Not good!)

I'm sure this man has exceptionally large lungs, but this record is a fantastic feat of endurance. By the time he finished the carbon dioxide levels would have been more than double normal and the oxygen levels would also have been low, but probably not as low as after avWR airbBH. (Pity they did not measure the oxygen and carbon dioxide levels in his first exhalation. However, that not easy because despite the fact that he started with full lungs, by the time he finished his breath hold there would not have been much gas to exhale!!) The shrinking lung volume also causes pain and activates breathing movements he must withstand to break the record.

So a magnificent medical, physiological, and athletic feat - but nothing to try at home without supervision! Even world class breath hold athletes have drowned when they have trained alone in swimming pools.

Sorry for the long post, but it is a subject close to my ❤️! 😀😀😀