Here's my take on punching. About ten years ago, a guy I was playing with playfully hit me in the abs. And the. next guy playfully punched my pec. The coincidence that two guys in a row spontaneously punched me got me hooked. They were aroused by my muscles, and that a could "take it." I was aroused by this act of first NOTICING the muscles, and then this rather innocent and brief act of "domination ". I started asking all future "partners" to punch my muscles. With time, and guys who actually LIKED muscles, some experimentation happened, to the point that I now get ALL the muscles punched. Yes, calves, forearms, lower back. It's not random, I guide the other guy as to the frequency and intensity of the punches that will stimulate a pump. This is what I crave above all now, and I wish I'd discovered it years earlier.