With the dumbbells on the floor, stand close to the dumbbells with your feet a little narrower than shoulder width apart. Bend at the knees and grasp each dumbbell. Get into a squat position. Keep your head up and the dumbbells at your sides. Drive through with your legs as you lift the weights up until you are standing in an upright position with your back locked. Keep the dumbbells close to your body and squat back down, lowering the weights to the starting position. Do not allow muscles to relax before next repetition.
Here are a few suggested alternative exercises:Back Extension - MachineBall Rise and ShineDumbbell Good Mornings