There are lots of them. One enterprising swim coach figured out that you could swim breaststroke much faster if you brought your hands forward above the water i

There are lots of them. One enterprising swim coach figured out that you could swim breaststroke much faster if you brought your hands forward above the water instead of under it. This'hack' gave birth to the Butterfly Stroke. Another figured out that swimming upside-down under water was faster than back-stroking above the water. Alas, this innovation was banned. And so it goes. Politics gets into it, as anyone who followed the UCI's wars with Graeme Obree would remember: http://en.wikipedia.org/wiki/Graeme_Obree http://en.wikipedia.org/wiki/Graeme_Obree