What is the meaning of "beefy pecs and beer gut"?

Secretly, I preferred the jockish types found solely at frat parties and raucous keggers. You know the type. Big arms. Beefy pecs and slight beer gut. Guys who don’t care about your scars. Who are incapable of being gentle. Who are all too happy to tirelessly ***, piston-like, and definitely not upset when you slip out afterward without giving them your number