Exercise would be a doubly efficient venture if people could split into two halves and have both body sections burn calories simultaneously by riding a tandem bike. Today's Groupon makes the most of feasible workouts: for $25, you'll get a two-month membership to Curves, a fitness center designed exclusively for women. Your Groupon is good at any of 30 participating locations in the St. Louis area. Your membership gets you unlimited visits, free weight-management classes, and a one-on-one coaching session and tour on your first visit.

With machines set up in rows to encourage competition, many ordinary gyms cater to men's bodies and psychology, right down to the urinals that were "accidentally" installed in the women's locker room. At Curves, you'll move around a circuit of hydraulic resistance machines that have been designed to work with women's bodies and promote weight loss, protect against osteoporosis, and deal with arthritis. Instead of fiddling with weight stacks and losing your momentum, the hydraulic machines use your body weight and fitness level to create resistance that matches your abilities, decreasing the risk of soreness or injury. Because traditional lift-and-lower motions create bulky muscles, each machine uses push-and-pull motions to create toned, lean muscles perfect for crushing a grapefruit without looking like you can.

For 30 minutes, you'll move around a circuit that positions machines inward so that you'll have a chance to laugh with your fellow fitness frontierswomen. Because you're all at different stations, you won't feel like you're in competition with anyone but yourself—and a soundtrack of fun, upbeat music will include cues to let you know when it's time to move on to the next station. You'll raise your heart rate and burn calories during a complete aerobic and strength-training workout. Meet new friends and plan a girls' night out between labored breaths, or invite along some of your current friends as friends instead of as shields against the creep ogling you at the juice bar.

You must begin your two-month membership within three months of purchase.

Reviews

Across the nation, women are singing the praises of Curves. Epinions users give the fitness center a solid 3.5 stars, while ViewPoints reviewers give it a near-perfect 4.4:

• Curves Fitness Center for women has ongoing support and encouragement..something not found in every fitness center. Curves is a place for all women...size, shape, age doesn't matter. What does matter is improving ones [sic] individual health and fitness and overall lifestyle. – nrscaree, ViewPoints
• Having different stations to work at, not only expels bordom [sic], but the different stations keep your interest peaked. The music is upbeat and after a while, you can recognize the songs and really get into the beat. I also was impressed with the attentiveness of the trainers. – harvardmom, ViewPoints
• Oh, sure, it's hard work - exercise does NOT come natural to me but the encouragement of others is most helpful. The knowledge of the equipment of the employees is also a huge benefit. – tart12341234, ViewPoints