This new core routine simply could not go without a video tutorial. Although some moves may be completely made up, believe me when I tell you they work. You can do sets of 10 or 20, choose your poison, but make sure you go through them at least twice!
In and Out Superman
In and Out Plank Twists
Knee-in Push Ups
Alternating Plank Twist Kicks
Bicycle Crunches (you can do these lying down or propped up for added intensity)
Dumbbell to Leg crunches (opposite arm & leg / do each side)
Alternating Reverse Plank Abductors
Slow Flutter Kick Raises
Circle Leg Throw-Downs
Now, you can work back up from the bottom or start from the beginning and repeat!