Biceps and baseball

I have often wondered about so many of today's baseball players who have bulging biceps. Certainly they play some part in the motions of baseball, but a major part? In hitting, it is the forearms and legs that provide most of the thrust.

Speaking of muscles, I remember Ted "Big Klu" Kluszewski, who was muscled up a lot like you see today. He was an imposing physical specimen at the plate.