Move along for a maximum core workout that blends traditional strength moves with balance challenges. Follow along with Prevention fitness expert Chris Freytag in this 2-minute exercise video and learn a great move to help boost your metabolism. Watch High-Metabolism Workout: Knee Hugger Chest Fly, and try an exercise that really works your upper body. Follow along with Chris for an exercise called the Knee Hugger Chest Fly. Start by sitting on your mat with your knees bent. Holding a weight in each hand, keep your knees bent and roll all the way down to the floor. Take your arms to the side, holding your weights with your palms facing in. Bring your arms up and weights together above your head, as though reaching around an imaginary tree trunk. Return your arms to the ground and repeat this move. Really squeeze your chest muscles as you move your arms all the way up. To target your abdominals, add in the next move: Bring your feet off the floor, roll your hips up 2 to 3 inches off the floor, and then lower. Make sure to keep your abs tight during this exercise to protect your lower back. As you do this move, imagine you’re zipping up a pair of jeans that just came out of the dryer and are a bit tight. You’ll really work both your abdominals and chest muscles with this exercise.  Join Chris and burn more calories with the entire High Metabolism Workout video series.