Speed Limits Ahead

Thanks to improvements in training and equipment, elite human runners have gotten faster decade by decade: witness Jamaican sprinter Usain Bolt’s gold-medal-winning performance in Beijing. But we may be approaching our physical limit, says biologist, mechanical engineer and marathoner Mark Denny. A professor in marine sciences and biomechanics at Stanford’s Hopkins Marine Station, Denny crunched the data—the world’s annual best times for both men and women, over various distances, going back a century. He projects that while men might shave another 0.21 second off Bolt’s 9.69-second time in the 100-meter, and women could gain as much as 0.1 second, that’s about as quick as is humanly possible. Here’s a look at how Cardinal standouts measure up to Denny’s data.