Sorry I know every few years the topic of "could a big regular guy beat the small MMA fighters" comes up. Generally we've always accepted a few key points: Size can overcome skill at some point Most people simply don't have enough of it to seriously challenge professional FLW and BW fighters For the sake of the discussion let's exclude female fighters This excellent post by Seaside a couple years back briefly goes over the average body types in the UFC by division. There comes a point where a fighter's "frame", determined by bone size and skeletal structure, sort of plateaus at the higher divisions. This is what allowed Vitor Belfort, Wanderlei Silva, Rampage, etc to jump from 185 to 205 to even heavyweight. Now most UFC bantamweights weigh in the ballpark of 150-160 lbs. While this is well below average weight in the developed West, I don't think this is as insignificant as the meathead manlet-haters like to believe. When most people think "160 lbs" they think of a swimmer or a cross country runner. One of my closest friends is 5'5" and about 150 lbs reasonably lean. He balloons to 175+ lbs off his diet. He is built almost comically thick, with probably the largest wrist circumference and head you'll see at his height, but he's also very strong. When he shoves, it feels hard. When he bumps into you, it feels heavy. I don't think that's a trivial amount of mass. UFC flyweights and bantamweights are very powerful for their size. I think you need to be in the smaller divisions else you get weeded out early. When I just intuitively picture what it'd be like if my buddy was more explosive and knew how to throw a proper punch I just can't see too many men brush it off like nothing, even big football players and weightlifters. Think about how much exertion is necessary to control a live 160 lb weight.