When runners step on the track, they’re usually thinking about pace, effort and positioning—not the shape of the track itself. However, according to one French mathematician, the design of the Paris 2024 Olympic track may have cost Great Britain’s middle-distance star Josh Kerr the men’s 1,500m gold medal.
Because the Stade de France also hosted rugby competitions during the Games, the athletics track was apparently built with a slightly altered radius–one metre longer on the bends and three metres shorter on the straights in comparison to a standard athletics track.
Amandine Aftalion, a mathematician at Université Paris-Saclay who studies the physics and statistics of human kinetics, says this subtle design change may have given the eventual Olympic champion, Cole Hocker of the U.S, an advantage.
According to Aftalion, the longer bend increases the centrifugal force, which is the outward force a person, object or thing experiences while turning. Centrifugal force makes it tougher to maintain speed in the curve. In the final 200 metres of the Olympic final, Kerr used Lane 2 to move ahead of Norway’s Jakob Ingebrigtsen, while Hocker hugged the inside of Lane 1 and waited for a hole to open up.
“The longer bend meant more time under force,” Aftalion said. “Kerr’s move into Lane 2 [the longer route] may have cost him momentum, while Hocker conserved speed and energy by staying tight on the inside.”
She adds that on a standard track, with shorter turns, Kerr might have been able hold off Hocker. But that extra metre could have been the margin that put the gold into Hocker’s tactical hands. The two athletes were separated by just over a tenth of a second, with Hocker winning gold in an Olympic record of 3:27.65, and Kerr taking silver in 3:27.77.
Although Aftalion’s theory may sound far-fetched, some studies suggest otherwise. Even though middle-distance runners aren’t moving as fast as sprinters, centrifugal force still plays a role in the amount of energy an athlete expends on the bends. A 2018 study in the International Journal of Physical Education found that track curvature can influence speed and efficiency, particularly in the final stages of a middle-distance race, when lactic acid and fatigue set in.
One thing that weakens the theory is Hocker’s ability to win races repeatedly, no matter his position heading into the final lap. Just a few weeks ago at the 2025 World Athletics Championships, the American pulled off more late-race heroics, surging from 12th to first with 400m to go in the men’s 5,000m to win gold for Team USA.
So maybe there’s a case for Aftalion’s theory around Kerr’s decision to swing wide into Lane 2, derailing his wheels, but the American has shown no signs of slowing down since then.
