Hold a dumbbell in each hand or just on the side of your body that you'll be bending. Plant both feet on the floor, shoulder-width apart. This is your starting position. (Aniston also likes to hold a kettlebell in one hand similar to windmills.)
Stretching your right obliques, lower the kettlebell down your left leg and draw your ribs toward your left hip.
Contract your right obliques to straighten your torso to return to the starting position.