Even if athletes never got any stronger or faster, and if their techniques and training never changed, they would still break records from time to time. That’s because the ability of each person who decides to compete, and the outcome of each competition, are affected by random processes. What happened on the way to the track that might affect the athletes’ performance? What’s the weather like? And so on. Every sporting event is a matter of chance as well as of achievement, and chance always offers the possibility of a breakthrough.
That said, the mathematics of record-breaking—also known as “extreme-value statistics”—tell us that, all things being equal, the frequency of world records will tend to diminish. At a certain point, we’ll have rolled the dice so many times that the chance of our beating our best score drops close to zero. That’s why new sports and new classes of competitors typically produce more records than old ones. Women athletes weren’t allowed to compete in the Olympic marathon until 1984. Since then, their record time has dropped by about 10 minutes, while the men have managed to shave off only five.
Good read on one of the more interesting aspects of Olympic competition.