Usain Bolt's Unusual Running Stride

There's something unusual about Usain Bolt, other than he's the fastest sprinter, ever. He's also unusual in that his running stride is asymmetric. According to researchers at Southern Methodist University, his right foot strikes the ground with 13% more force than his left, and his left foot stays on the ground 14% longer than his right.

Most runners have close to symmetrical strides, with left-right differences of less than 3%. Running coaches generally assume that symmetry is desirable for speed optimization. But is it? It's possible that Usain Bolt has subconsciously stumbled onto something (no pun intended) that improves humans' running speed. On the other hand, it is just as likely that his body has adapted to the fact that apparently he has slight scoliosis; his spine curves slightly to the right, causing his right leg to be a little shorter than his left. If that's true and if asymmetry is generally not desirable, then his rise to the title of fastest human is all the more remarkable.