UFC women's Ronda Rousey appeared recently on the JIM Rome show, and discussed the "women weaken legs" rule in fighting.
“For girls it raises your testosterone," explained Rousey. "so I try to have as much sex as possible before I fight actually. Not with like everybody, I don’t put out like a Craigslist ad or anything, but if I got a steady I’m going to be like ‘yo, fight time’s coming up’."
There are limits however.
“You can’t (beep beep) somebody and go fight that day," said Rousey in closing.