Primary Muscle Group: Front upper arms
Muscle Groups Worked in This Exercise: Biceps brachii (long and short heads and Brachialis
Preparation: Sit on the ball with the band under your right foot. Grasp the ends of the band with both hands. Extend your left leg straight out and extend your arms fully toward the floor with your palms facing away from your upper body.
Breathing: Exhale as you bend your arms and inhale as you lower back to start position.
Execution: Bend your arms and lift your hands to your shoulders. Return to starting position. Switch legs and repeat after completing all reps.
Comments: Because one leg lifted will unbalance you, your core muscles will work harder trying to keep you balanced.