Get celebrity abs! A Web exclusive

How do so many celebrities get tight, toned abs that look amazing in clingy clothes? The key is doing a variety of exercises, preferably every workout, to keep your muscles responsive, says Hollywood trainer Gunnar Peterson, whose clients include Jennifer Lopez, Julia Ormond and Kristy Swanson. Peterson and three other hot trainers-to-the-stars reveal their favorite ab moves and their best flab-blasting cardio tips. Here are four more amazing ab moves to help you mix things up. Your mid-section will be red carpet-ready in no time!