At an athletic meet for high school students, after my son was done with his long-distance run I stood by to watch hurdles race as I find it fascinating. The runners need to hit a rhythm: they take a few steps, jump and repeat. Another interesting thing is that as the distance between runners starts to grow, patterns start appearing as each runner’s rhythm is in a different phase from others, with one preparing to jump, another in the act of jumping and yet another already completing the jump.