Using a series interactive visualizations, Slate compares the winning times of Olympic champions from 1896 through 2008. Joyner objects:

The comparisons over time … are not entirely fair. Aside from the fact that today’s Olympians begin training much earlier—specializing in a single sport, receiving professional coaching, and typically devoting full time to their sport—there are vast differences in equipment and playing field. Today’s track events are held on rubberized surfaces engineered to maximize speed and the athletes wear clothing that minimize weight and wind resistance; it’s silly to compare their times directly with people running on cinder wearing loose shorts and heavy shoes.

Another interactive graphic maps competing nations since the modern games began.