Three very targeted, very different workouts — classic floorwork, stability ball abwork and stability ball/medicine ball abwork. It’s a combination that maximizes motivation while challenging your muscles in diverse ways (e.g. alternating segments in a three-day rotation). You’ll work the entire abdominal area from every angle, always carefully sequencing the routines to maximize effectiveness (e.g. isolating the lower abs first, then adding on multiple-muscle exercises). Cathe’s no-nonsense cuing is clear and precise. Requires a stability ball; Cathe uses an 8-lb. medicine ball, but a dumbbell also works (just not as comfortable). DVD’s “premix” feature lets you select three other workout variations.