There are some great ab machines and gym equipment that can get you a great ab workout. The problem is that not too many of us have full gym and all the relative equipment right at home. However, this workout was built for those of us who have a set of dumbbells or even a full 2 liter bottle of water. Using only one dumbbell (or full 2 liter), you’ll hit all the areas of your core for a grueling and rewarding ab workout that will have your mid-section toning up in no time.