The art of increasing your stamina not only through pure strenuous workouts, but also by the act of any form of sexual intercourse, including pelvic thrusting, bear-humping, tea-bagging, queefing, and of course all other sexual positions.
"Hey Kate you going to Jazzercise with me tonight?"
"Oh no you silly cunt Im going to Jizzercise! You get laid AND you get a workout! They even show you how to get work outs from simply queefing upside down!"
"Hell girly Ill go with you! Fill my butt with spermmm!"