This is a cool human interest story but I have no idea why it’s at the top of HN. A random ultramarathon not planning for a woman winning just isn’t that surprising or interesting.
HN readers upvoted it. That's literally all there is to something being on the front page.
From the guidelines: "Off-Topic: Most stories about politics, or crime, or sports, unless they're evidence of some interesting new phenomenon."
A woman winning a race is not a new phenomenon. A quick google search produces:
https://www.theguardian.com/sport/2019/jan/17/jasmin-paris-f...
https://edition.cnn.com/2019/08/06/world/fiona-kolbinger-win...
https://trailrunnermag.com/people/is-women-winning-ultras-ov...