Here’s an abdominal exercise from Denise Austin and Prevention that targets your core from every angle.

Start on your back with your arms at your sides. Bend your knees and lift them up so they’re over your rib cage.

Now for the hard part–pull your navel in toward your spine, contracting your abs and slowly start circling your knees.

Bring your knees down to the right, extend slightly out to the front bringing them around to the left and back to the starting position. Then reverse the circle. The smaller the circle, the easier it will be.

Go back and forth a total of ten times. Rest and repeat.