Grab a light dumbbell (2 to 3 pounds) and stand in a split stance with your right foot forward. Bend right knee and hinge forward from hips until your torso is parallel to the floor. Make sure back is flat and shoulders are square.
Holding the dumbbell in your left hand, lift your straight arm up to shoulder height. Square off shoulders and hips again. Raise and lower your arm 1 inch, keeping torso parallel to the floor and belly button drawn up and in. Lift chin off chest and keep arm as close to your side as possible. Do 30 lifts on each side.