For most of us humans, the aquatic dance is the same. We dive into a pool or a lake or an ocean, perhaps hold our breath for a few seconds as we swim underwater, and then surface to blessed oxygen.

Amber Bourke stands on the ocean floor, facing away from a black abyss while holding her breath. Slowly, she crouches down and pushes off, arching her back gracefully and spinning down into the ...

Try something right now: hold your breath for 5 seconds. Probably easy, right? Now, take a deep breath and double it: hold your breath for 10 seconds. Then 20. If you practice holding your breath a ...