From Washington Post:
Her mechanics, common among male swimmers but almost unheard of among women, is often described as a â€śgallopâ€ť or a â€śgiddy-upâ€ť stroke, or is said to have a â€śhitch.â€ť Ledecky has called it a â€ślopingâ€ť stroke. Essentially, instead of a steady, metronomic beat â€” left, right, left, right â€” her stroke is syncopated: short left, long right, short left, long right. She breathes almost exclusively to the right side.
Yuri Suguiyama, Ledeckyâ€™s coach from age 10 to 15, taught her that stroke in the spring of 2011 â€” about 15 months before she would win gold in London. To hear Ledecky tell the story, it was more or less accidental: She was doing a drill where she was asked to reduce her number of strokes per lap and had to lunge â€” or gallop â€” to reach the wall.
â€śShe was swimming more like a classic female distance swimmer,â€ť he recalled. â€śShe would breathe to both sides. She had kind of a sporadic kick, or what we call a two-beat kick. And I donâ€™t know â€” I just didnâ€™t like the way she swam. .â€‰.â€‰. I think I was watching [video of] a Phelps race from 2007. His legs were moving the entire time. He had a nice little hitch, or a gallop, and I was like, man, Katie could swim that way. .â€‰.â€‰. It just takes advantage of the aggression and the kind of fury that she swims with.â€ť
If the best female swimmer in the world swims one way, it would make sense for others to try to copy her. But it isnâ€™t that easy. The gallop stroke requires tons of core strength, the sort many male swimmers possess but few females do.
â€śWe found that itâ€™s a very hip-driven stroke, and I have really good rotation and rhythm with my hip rotation, and I get a lot of power out of my hips,â€ť Ledecky said. â€śSo that stroke kind of maximizes that.â€ť