Swiss-Ball Dumbbell Rotation
Sets: 3-4 Reps: 4-6 Rest: 90 Seconds
Hold a dumbbell with both hands and lie back on a Swiss ball so that your hips are parallel to the floor and the weight is straight out in front of you. Rotate as far as you can to the left, keeping your hips parallel . Then rotate to the right . That's one rep. Do not allow your hips to sag.