A very hierarchical relationship exists. In this case, the mayor is the head of the swimming federation. He's like the Emperor. Chiba therefore has to act like one of the village members. Because of the village mentality, failure is not just an individual matter.
Athletes are also terrified of being excommunicated from the group.
It's bad enough to lose, but then to think you'll be shunned after you lose. That's the characteristic of Japanese sports. It's pretty much an authoritarian system that rules. On the other hand, it sometimes helps. If she didn't win, it would have been a terrible thing.