Darin Steen of Major League Health demonstrates how to lose belly fat with stomach workouts. Using a boxing technique, you can get your heart rate up to 160 and boost your hormones to gain muscle and lose fat. It works your abdominal muscles in a unique side-to-side plane of motion to tone your midsection. Focus on pulling as much as you focus on punching. Use your pointer and deliver two punches on the right and then deliver two punches on the left while focusing on pulling. Increase the punches to sets of three, four and five for an intense abdominal workout.