Hibiki Sakura, a gluttonous second-year high-schooler, notices her waistline expanding and signs up at Silverman Gym. There she finds her school's prim honor student Akemi Souryuuin already training in secret as a closet muscle fetishist. Under the absurdly sculpted trainer Machio Naruzou, each episode walks through a real exercise, from bench press to squats to planks, by way of Hibiki's comic attempts at it. The cast around the weight room keeps growing, later picking up their history teacher Satomi Tachibana and the Russian transfer Gina Boyd.