If you're not dragging your abs to the gym as often as you swore you would, the city's best sources for in-home motivation are OmniFitness (multiple metro-area locations, including the newest store, 830 Broadway, near 12th Street; 212-260-8537) and Gym Source (40 East 52nd Street; 212-688-4222). Both have Websites (omnifitness.com, gymsource.com) that detail the full range of treadmills, stationary bikes, and other exercise equipment they carry, which, including delivery and setup, can run into the thousands (motivated yet?). For the less ambitious, both stores offer compact equipment (dumbbells, free weights, jump ropes) and one must-have accessory: an electronic body-fat analyzer. These handheld devices -- such as the Omron Body Logic 301 ($99, both stores) -- send a fat-detecting electrical charge (which you can't feel) through your body. Within seconds, you'll know if you should quit the Krispy Kremes and climb back on the treadmill.
To figure out whether your cardio workout is intense enough (or too intense), you've got to keep track of your heart rate -- either through manual pulse-taking or a chest-strap device that broadcasts to a receiver. The new Polar S510 ($240, polarusa.com) trumps both options, not only collecting data -- including recovery heart rare, caloric expenditure, cycling distance and speed -- but also sharing it with your PC via infrared. The Mio Fitness Watch ($119.95, shoplifestyle.com) takes a more streamlined approach to data-mining, collecting less information but dispensing with the chest strap: You check your pulse by holding two fingers on the triangular sensors.
The Mini Step and Flex ($99.95, Sharper Image, 4 West 57th Street; 212-265-2550) is a step above other compact stair machines: It has a digital display that tracks elapsed time and steps taken, plus bungee-cord-like resistance bands that allow you to work your upper body as you climb your way to buffness. It's sturdy for such a diminutive unit -- 25 pounds of solid powder-coated steel that can slide under a bed -- and very effective: Thanks to a fourteen-inch range of motion and the preset resistance of built-in shocks, you can work up a sweat before reaching the virtual tenth floor.
At least until ubiquitous high-speed access lets us sign up for online Pilates, it seems odd to get in shape on the Internet. After all, it's just a high-tech excuse for sitting on our butts all day. But at least a few fitness sites use interactivity to foster old-fashioned activity. Workoutplan.com creates customized exercise programs by setting goals and training schedules for every day of the week. It lacks the motivating force of a personal trainer pushing for one last rep, but it's free. (Getfit.com offers similar services in a glossier package for $96 a year.) If you want to calculate exactly how much exercise helps, Shape Up America (shapeup.org/fitness/assess/fset2.htm) offers a fitness assessment with take-at-home tests to measure flexibility, muscular strength, and aerobic fitness. Efit.com even tells you exactly how many calories you burn running, having sex, and -- oddly -- praying. Just don't count on that last one alone.