World Records

During the 2024 Paris Olympics, some of the best swimmers in the world competed in the men’s 100-meter breaststroke competition, but none of them set a new world record—and in fact all eight of the competitors would have finished in eighth place or lower had they been competing in the Tokyo Olympics in 2021.

Similarly unimpressive numbers (compared to other recent Olympic competitions, that is, as these were still objectively some of the best swimmers and paces ever recorded) were tallied in the women’s 400 freestyle.

On the final day of the 2024 Olympic swimming events, four all-time world records were set, and 17 Olympic records had been set—which was the lowest record-breaking count since 1996, though not completely anomalous. But there were murmurings that the swimmers may have been competing in a “slow pool,” and that it took them until that last day to adjust their performances to account for its peculiarities.

In this context, a slow pool is one that is built in such a way that swimmers are fighting more turbulence than they would typically encounter, and the pool in which they were competing was indeed unusual on several fronts, largely because it was temporary and built in a rugby stadium for these Games.