re: Could you beat a 135 pound female mma fighter (amanda nunez)without training?

A jujitsu chick would undoubtedly beat many untrained men in just jujitsu...where a man isn't truly trying to hurt them. That whole calculus changes when a man is truly trying to knock them out.

In early UFC, in addition to people being mostly ignorant of submissions, Gracie wore a gi. That attire gave him leverage and dry grip points to help leverage vs larger opponents. He pretty much refused to fight without the gi.

Without a gi, there are few submissions after people get sweaty. You have neck chokes, mostly after the person decides it is better to take that than punches to the head. A man should have the physical capability to weather any storm from a 135# female and will quickly be sweaty enough to make submission extremely difficult for her.

Bone structure also helps the man. It is easier for him to control her wrists, as the diameter will be smaller and his hands larger. The difference in gender is just too much for n avg 200# man and a 135# woman.