Although body-exchange programs mean no one ever has to stay in one meat suit for long, returning yours in bad condition means you forfeit your deposit. Keep your constitution in returnable condition with today's Groupon: for $20, you get four Pilates mat classes at Streamline Pilates Studio (an $80 value).

The certified instructors at Streamline Pilates Studio encourage fitness for athletes and unathletes of all experience levels. Each 50-minute class is designed to strengthen muscles and increase flexibility without adding bulk, resulting in improved posture, greater ease of movement, and the ability to steer cars with one’s mind. Mat essentials teaches fundamental Pilates moves, which rely on the student's own body weight to gain core strength without additional equipment. Weekend morning sessions focus on breathing and stretching to relax the body and energize the mind. Advanced practitioners can opt for classes that employ props to create a more challenging experience, much like adding a grand piano to a bungee jump. Classes generally hold a small group of 14 to 18 fitness-seekers, so check the studio's schedule for availability.