The fans of the lighter weight divisions often complain about fighters in heavier divisions having "beach muscles." Their belief is that big muscles don't help one's athletic performance and their only use is for looking good at the beach.
Anyone who has ever trained with weights for a decent amount of time has noticed that when you train by forcing muscles to get stronger, the muscles get bigger! Remember when you or your friend broke his arm and his arm was in a cast for 4 to 6 weeks? When the cast got taken off, after all that time being inactive, the muscles in that arm had gotten smaller and the arm was weaker than before it was broken.
The bottom line is your muscles don't get stronger when you train for strength without also growing in size. You can't get significantly stronger without your muscles also getting bigger.
Anyone who has ever trained with weights for a decent amount of time has noticed that when you train by forcing muscles to get stronger, the muscles get bigger! Remember when you or your friend broke his arm and his arm was in a cast for 4 to 6 weeks? When the cast got taken off, after all that time being inactive, the muscles in that arm had gotten smaller and the arm was weaker than before it was broken.
The bottom line is your muscles don't get stronger when you train for strength without also growing in size. You can't get significantly stronger without your muscles also getting bigger.