Before you proceed reading this article, go ahead and time how long you can hold your breath. How long did you last? Forty-five seconds? A minute? Now imagine that instead of sitting at your computer/phone, you’re instead totally submerged underwater filming a big action sequence in a blockbuster movie, performing specific choreography and needing to hit specific marks. Do you think you’d still be able to hold your breath for even close to the same amount of time?