The OP article said the same thing, and like this article, it provides no evidence for the statement. I looked for some numbers, and for world bests, men had better performance in every category I found. The study linked below looked at speeds over decades and in every case men had better performance. Both men and women have improved over time, and as a percentage the difference is getting smaller, but in absolute difference it appears the same. It is an admittedly brief search, but I can't find evidence in the form of measured times (not conjecture about estrogen) indicating at all that women perform better in ultra marathons. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3870311

[–] Pips@lemmy.sdf.org 1 points 1 week ago

Those are athletes. To really know, you would need to use average people going for the same time/distance at more moderate speeds. While the fastest men are probably faster than the fastest women across most any distance, I doubt we have good data on average men and women going the same distances.