Mens health14 Aug 2024South Beach's Most Popular Gym Is on the SandThe outdoor fitness park at Muscle Beach South Beach (MBSB) in Miami sprouts from the coral sand at the intersection of Ninth Street and Ocean Drive. A cadre of improbably toned bodies float off the bars, performing freestyle-calisthenics moves like the human flag, cross, and lever. MBSB has been a workout destination since the 90s, but in the past year its popularity has soared.