LOL, reminds me of a true story.
Happened at Arnhem, when the Brits were trying to advance over water, - in little boats, while basically being massacred by German machine gun fire and artillery.
One boad toppled, dropping the whole and loaded crew into the water. This was wittnessed by soldiers who had made it ashore.
One gunner, wrapped in ammo belts sank like a stone.
Anyway, less than a minute later, a soldier on the bank saw a helmet coming out of the water, then a head, then a whole soldier, WALKING out of the water.
He was so heavily loaded that he sank to the bottom, which was smooth and not so sticky, so he walked.

to that guy for holding his breath, orientation and guts together.