The mid week ab workout is called the hollow body rock. To perform this ab workout you will start by laying on your back. Next step raise your feet and shoulder 4-6 inches off the ground. Keeping your core tight throughout the set you’re going to rock back and fourth. When your feet are on the ground your shoulders are off the ground. When your shoulders are on the ground your feet are off the ground. Remember to keep your core tight throughout the set. 5 sets of 25 reps.