When compared to mixed-gender populations, the members of all-female lizard species are stronger, happier, and 10 times more likely to be named Trisha. Today's Groupon brings together likeminded ladies to increase fitness, morale, and results: for $30, you get a 60-day basic membership to Curves (a $68 value), including one Curves Circuit with Zumba Fitness class and the initiation fee (a $99 value; a $167 total value). Choose from 16 Tampa-area locations.

Members at Curves, a fitness center designed exclusively for women, rotate around a circuit of hydraulic resistance machines designed to help female bodies lose weight, prevent osteoporosis, and manage arthritis. An experienced trainer watches over the space, helping participants maneuver machines and build muscles. Instead of fiddling with weight stacks and losing momentum, the hydraulic machines use the exerciser's body weight, fitness level, and aerodynamic water bottle to customize the amount of resistance, decreasing the risk of soreness and injury. Unlike traditional lift-and-lower motions, which can create bulky muscles, each Curves machine uses pushing and pulling to create toned, lean muscles perfect for crushing grapefruits.

At Curves Circuit with Zumba Fitness classes ($4/class after the first free class), women move around a circuit that positions machines inward, letting them share laughs and secret handshakes with fellow fitness frontierswomen. A soundtrack of fun, upbeat music includes cues that tell participants it's time to move to the next station or bust out one of Zumba's Latin-inspired dance-aerobics moves. The combination of cardio and strength training raises heart rates and burns calories while allowing women to meet new friends, arrange a girls' night out between labored breaths, or plan a bikini dress-up party for their newly svelte doppelgänger action figures.