Like tug-of-war tournaments and harmonized singing telegrams, workouts are more effective when done with a group. Join a fitness community with today's Groupon: for $20, you get a 30-class fitness pass to MetaBody (a $350 value), which is valid at 20 Washington-area locations.

The inspiring trainers at each MetaBody location lead troops of workouteers in results-oriented workouts several times weekly. Sweat sessions utilize a variety of exercises and disciplines to produce full-body results in a supportive environment, ideal for beginners and hard-core core-hardeners alike. During any class, motivational instructors will use the instinctual distrust of routine to their advantage. Begin a day of litigating with a refreshing early-morning boot-camp session, or wind down by burning evidence and pounds with a late-evening yoga class. Muscles are kept guessing with new and challenging moves during each session, so participants never fall into a boring, ineffective routine, such as regular teeth brushing. In addition to the fitness classes, students receive a success guide to help prepare for imminent pound loss, a nutrition guide, and a $100 gift certificate for individual coaching. Because the pass sets a 10-class cap at any given location, roving fitness mavens can further shake up their workout regimens by vetting a series of classes or instructors that work best for them.