Lance Armstrong is some kind of machine. This article on MSNBC details all the ways in which his body is simply better built for the sport of cycling.
Also, here's a great article from the Christian Science Monitor that details how cycling is, in many ways, more of a team sport than football or basketball. In cycling, all the teammembers sacrifice themselves for the success of the one. That probably says a lot about why cycling is not a more popular sport here in the United States.