With shoulder width stance, grasp fixed bar or support at hip level with one arm.
With hips and waist straight, bend knees to allow body to fall backwards as knees come forward. Allow heels to raise from floor. Lower body until knees are almost fully flexed or near floor. Return to original position by extending knees as heels return to floor.
Keep waist and hips straight throughout exercise. Knees should point same direction as feet throughout movement. Also see Sissy Squat on apparatus.
Movement can be made easier by placing arms further down away from head as shown.
Exercise can be made more challenging by placing hands further up toward head or by holding a small weight plate on chest.