The most secretive body parts are muscles, which hide behind layers of skin and appear only occasionally to help lift cars off trapped kittens. Flex your biceps in the absence of a cat emergency with today's Groupon: for $20, you get 20 drop-in classes plus full facility access at Fitness NW/Only Women's Fitness Club on Northwest Silver Springs Boulevard (a $315 value).

With an extensive selection of classes and modern-marvel machines in its co-ed and women-only gyms, Fitness NW/Only Women's Fitness Club satisfies almost any fitness fiat. Build on the benefits of a group mentality with classes that run, heft, or stretch seven days a week. A host of options allows members to shape and chisel according to their priorities, from the core-crunching Abs-Salute to the Kickbox Combo, in which students exert anger upon the unsuspecting atmosphere. Gym rats that prefer to strike out on their own can sample free weights, circuit-training stations, treadmills, and a slew of sexiness-sculpting machines. Other amenities include a sauna, juice bar, and child-care services for members whose progeny have grown too large or ornery to bench-press.