Lie prone on ball with feet against base of wall. Place arms parallel out over floor beyond head.
Raise torso off of ball and hands over head by hyperextending spine. Return torso to ball and hands toward floor. Repeat.
If no wall is available, hips can be positioned lower on ball and toes can be positioned out wide on floor for balance.
Movement can be made easier by positioning hips low on ball and by placing arms lower. See Arm Position During Waist Exercises.
Exercise can be made more challenging by positioning ball lower toward hips or by adding weight. Exercise is also more challenging on hyperextension apparatus.