There are five muscle groups that make up the abdominal muscles: rectus abdominus, external obliques, internal obliques, transversus abdominis and pyramidalis. This suggests two things: first, abdominal muscles are a lot more complex than we normally think and that makes them harder to target and harder to train properly. And, second, the abdominal muscles must have a far more complex and important function than we think. Both of these are true, which is why the "Hard Abs Workouts Collection" provides you with a handy set of workouts you can try to keep your abs strong, develop effective range of movement of your body and maintain overall body health and efficiency. Strong abs help combat muscle fatigue, protect you from injury when lifting, jumping and running and help increase your overall power.