Then He'll slow down and get tirerd faster. He fights at that wieght, cause it's the ideal wieght to fight at for his body

Smart fighters test thies things out trust me. and BTW coontrairy to popular belive size does not = strength and speed or else Some one like Giant Silvia or Bob Sapp would be the best fighters in the world. When I started MMA I was a BB at 235lbs and some dude who was 170lbs knocked me the f*** out now I fight at 190-200max but the ideal for me is 190 or 195 In boxing my Ideal weight is 180. Remember a split sec makes a big differance againgst a trained fighter

And if your untrained against some one who is, you'll last seconds.
People must remeber whatching fights is 1,000,000 times easyer than beeing in the ring, when ur in there a lot of things change in a quick hurry! I learnd this lesson the hard way.