[trashface]

A kind of off topic question: in that video you can see that not only is Katie breathing every 2 strokes, but her stroke timing is "staggered" - 2 strokes, pause, 2 strokes, pause - like a heartbeat. I think Phelps does the same thing. Is this just a style thing or is it actually faster?

[GreedCtrl]

This is called galloping (might have other names too). In general, freestyle has two extremes: shoulder driven and hip-driven. Shoulder driven freestyle is faster but less efficient, and hip-driven is slower but more efficient. Galloping alternates between hip- and shoulder-driven strokes, which is why it seems uneven. This also allows the swimmer to take advantage of the motion of breathing to build more momentum. I don't know if it is truly faster or not though.

[trashface]

Thanks! They definitely didn't teach us to do it that way when I was a kid, but that was back in the dark ages. I'll have to try it to see if it works for me.

[xyhopguy]

I dont think this is settled -- I've seen world class swimmers do it both ways. Personally I find taking a long stroke after each breath more effective.