Brides without the resources to hire a personal fitness guru now have a fine substitute, courtesy of trainer-to-the-stars David Kirsch. Kirsch’s famously fast-acting regimen is virtually carb-free and requires Zen-like dedication to a daily schedule. In his latest book, The Ultimate New York Diet, he tailors his plan for urban types, offering a number of “express workouts” that can be done on subway platforms or in office cubicles. (Most of the clients profiled report improved skin and healthier hair, thanks to the nutrients supplied by the diet.) Kirsch also includes success stories from people with a wide variety of body types—from Heidi Klum to his own 69-year-old mother—so there’s no temptation to attribute the success stories to nothing more than good genes.