Looking for an intense interval challenge? This video is for you! Give this workout a try along with the other workouts in Sarah's 4-week slim down series to burn a ton of calories, increase muscle definition and get toned and tight. In this 37-minute workout Sarah takes you through 20 different dynamic movements, each performed for one minute. Most of the movements use a hand weight, which is optional, to take the intensity up a level. This workout will work the entire body from lunges that hit