Take it up a notch! Tone your arms, flatten your stomach, and strengthen your legs. In order to advance your fitness level it's important to add variety to your training. Challenge yourself with this Suspension Trainer workout designed to strengthen your stabilizing core muscles. Kelly's detailed instruction and boundless energy will leave you confident that this total body workout is the most fun you'll ever have working this hard. So go on and try it, but be warned, these Grokker Premium workouts are every bit as tough as they look.