I have no clue what the exercise is called, but I believe it is supposed to target your obliques(?) sides of your torso. You lay on your back, knees bent as though you are going to do a sit up... then you roll your body either to the right or the left so your weight is on your hip. Then do a crunch in that position. Like doing a sit up, but at an angle. I know that will help tone and slim down the waistline. As far as actually losing fat on the waist, I think that generally good nutrition and good exercise routine will slim you down all over. And if you carry a lot of your weight in your stomach, I think that is where you will notice the most change. That's just my uneducated opinion...