Chairman Maoundy said:
https://www.reddit.com/r/todayilearned/comments/2ce59h/til_the_worlds_strongest_woman_arm_wrestled_an/ (They clearly aren't "average men")
I know that it's not scientific or anything, but it just shows that women are naturally weaker, cuz biology n' shiet.
The man had bigger biceps.
The man was using his whole body weight to pull, essentially cheating.
The man hadn't just arm wrestled another person.
The man had slightly shorter arms giving him more leverage.
Gender biology only comes into play at the upper echelons of bodybuilding. The difference between the fastest female sprinter and the fastest male sprinter is pretty small (about a second), despite the 100m being the most optimised sport ever.