Weight lifting won't necessarily help in a fight if you have a complete lack of fighting knowledge or technique to back it up. In a like for like weight class, a bodybuilder would not beat an MMA fighter, and even in most cases where there is a bigger bodybuilder, their lack of fight knowledge, endurance, and fighting IQ will lead to their demise. Learning the art of kickboxing, Mauy Thai, and striking will win fights. There are levels to fighting and bodybuilders or people who just lift weights rarely come out on top.