A male erection caused by excitement related to working out or getting your pump on.
Friend 1: "Dude, look at this tool decked out in Tapout."
Friend 2: "What a douche, he's probably got a swoner thinking about repetitively lifting heavy shit."
Ex.2 "Dude i have a throbbing swoner, it won't go away till I hit the gym.......... WTF!!!!! Did you use the rest of my muscle milk!?!"