Arm Wrestling?

When me and my girlfriend arm wrestle, it usually is a pretty neutral matchup, with both of us getting small advantages, with me getting a little more advantages than her.. But , either our grips slip or she just stops trying because she says that she loses momentum. She says that she could beat me if those things did not happen. I say that she can't. So, we put a time limit on it of about 20 seconds to see who was ahead at that point. Right handed was neutral and left handed resulted in her having a very slight advantage. Who do you think would win if we were able to determine a winner?