A. Stand to the side of step, with left foot on top of step. Lower into a squat, reaching both arms straight out in front of chest.
B. Rise up out of squat, and as legs extend, shift weight into left leg and stand up on top of step, bending right knee and curling heel behind body as you tighten abs, squeeze inner thighs together, and bend elbows behind torso. Step back to the starting position, and repeat. Complete all reps on the first side; then switch legs and repeat to complete the set.