Long before Rousey learned how to throw the perfect jab or check a leg kick, she'd already mastered the move she would someday use to rule mixed martial arts. As a child, Rousey learned the armbar from her mother, former judo world champ Dr. AnnMaria De Mars. Rousey, who followed mom into judo and became the first American woman to win an Olympic medal in the sport, knew the armbar would allow her to dominate MMA. "I believed that from my judo skill alone, I could win every fight," Rousey, 27, says. So far, so good: The UFC's first female bantamweight champion is undefeated and has finished all eight of her pro fights with a variation of her trademark. So we asked the master-at-armbars to school us on how she finishes off her foes. -- Brett Okamoto