15 Minute Workout: Fresh Flat Belly Moves
15-Minute Workout: Fresh Flat Belly Moves Chances are, you've already elevated your ab work onto a stability ball . Smart move: Research shows that crunches atop a ball are approximately twice as effective as those done on the floor. But stop there and you're selling this multitasking tool short. "Most people think a stability ball is just for strengthening their core, but training with a ball can tone muscles throughout the entire body," says personal trainer and fitness author Larysa DiDio. "It also improves flexibility, balance, posture, and coordination." Plus, by swapping your old go-to moves for the following innovative workout, you'll wake up your body and shock it into burning more calories. You'll also increase cardio and muscular endurance (how long your heart and muscles can push before calling it quits). Three times a week, complete this workout, created by DiDio, as a fast-paced circuit, moving f...