They way they do it is by breathing pure oxygen from a tank before go underwater. The air we breath is only 21% oxygen. This means they have about 5 times as much oxygen as you would if you breathed normal air before going under.
They way they do it is by breathing pure oxygen from a tank before go underwater. The air we breath is only 21% oxygen. This means they have about 5 times as much oxygen as you would if you breathed normal air before going under.