Fans of celebrity fitness trainer Jillian Michaels know that despite the fact that one of her workouts is under 30 minutes, it will be a challenging one. And Michaels’s Shred-It with Weights workout is just that: an efficient, fun, adaptable routine that will show results in less than a week. But don’t expect any down time to rest or daydream. Michaels keeps things moving at a brisk pace, even in the beginner version. You’ll be able to need a small weight to do the routines. Michaels recommends the trendy kettlebell, but a regular four-pound dumbbell will work just fine. Then get ready to get your heart rate going. Michaels’s routines include some cardio moves with weights, like swinging the weight around the body, to keep the heart rate elevated, and to further tone the muscles. She also is a fan of lunges, squats, and leaps, all with the added resistance of the small weight. As at all times, Michaels offers several options–a modified routine for true beginners, and an even more advanced one for many who in point of fact need to challenge themselves. The DVD also includes an important tutorial by Michaels on how best to care for a kettlebell, to keep it in keep an eye on and to avoid injury. If your goal is to pack as much toning into one half-hour workout as imaginable, Jillian Michaels’s Shred-It with Weights is the ticket to a more chiseled physique. Ready? Let’s go, people! —A.T. Hurley