The Jamaican sprinter and her Olympic record time captured everyone’s attention. What’s underfoot, though, might have been a factor when Elaine Thompson-Herah broke a 33-year-old Olympic record in the women’s 100 meters.

It’s shaping up as a fast track surface at Olympic Stadium. Runners are certainly on track to setting personal, Olympic, and possibly even world-record times over the next week at the Tokyo Games.

The brick-red track is made by Mondo, a company that’s been around since 1948 and has been the supplier for 12 Olympic Games. This particular surface, according to the company, features “three-dimensional rubber granules specifically designed with a selected polymeric system that is integrated into the top layer of MONDO TRACK WS that are added to the semi-vulcanized compound. The vulcanization process guarantees the molecular bond between the granules and the surrounding matter, creating a compact layer.”