[baddox]

According to the Wikipedia article of Olympic weightlifting world records, the 69kg men's record total lift is 359kg, while for women that record is 286kg. That's about a 25% difference.

Of course, world records might not be the best thing to look at, since the variance among the genders is probably different (although this discussion is about top MMA fighters, so it's fairly appropriate). Also, you can probably find very different numbers by looking at different weight classes and events.