Primary Muscle Group: Low Back
Muscle Groups Worked in This Exercise: Gluteus Maximus, Semitendinosus, Semimembranosus, Quadratus Lumborum, Iliocostalis Lumborum.
Preparation: Kneel on the floor and bring the ball up close to you. Lie forward on the ball with your abdomen right on top of the ball and place both palms on the floor in front of you in a wide stance.
Breathing: Exhale when lifting/extending, Inhale to release down.
Execution: Lift your right arm and your left leg - exhale. Then, as you lower them down again, inhale. Alternate sides after completing all reps.