[fluffything]

> Barely, if any, difference between the sexes in races at this distance.

Are there any facts that back up this claim?

50k is barely over marathon distance, and there is a huge difference between woman and men on marathon distance (~2:01 for men vs ~2:15 for woman (10% slower).

I don't know of any longer distance running event in which such a gap doesn't actually increase. That is, the larger the distance, the slower woman actually become relatively to men.

At the far end, for example, for the Spartathlon (https://en.wikipedia.org/wiki/Spartathlon), the fastest men complete the distance in around ~21 hours while the fastest woman takes ~24 hours (13% slower). If you look at the times of the top 3 males and woman of each year, most years top 3 mens finish in ~<24 hours, while women are at ~<31 hours.

It might be interesting to visualize the gap per year vs the temperature. There are some studies about how heat affects the running performance of men and woman in marathon distance races, but not so much for long distance races (https://insights.ovid.com/article/00005768-200703000-00012). IIRC (don't take me for this), heat affects slower runners more independently of sex.