From a seated position, lean your torso back and bend your knees with your toes lightly touching the floor. With a weight or just your hands clasped together, rotate your torso to the right, bringing the dumbbell or your hands as close to the floor as you can. Come to center, and repeat again on the left, all the while, keeping your abs engaged and tight. One twist to the right and then to the left is considered one repetition.
Helpful tips and Tricks
If you are using a dumbbell, grab both ends instead of the handle. Also, the more you lean back, the more difficult the move becomes.