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A Kick Butt Cardio Routine In this week’s High Intensity Interval Training routine; IFBB Pro Jessica James, shares a booty blasting 2-part session using the Stair Stepper machine. There isn't specific number of rounds you must complete; however, the goal is to get in as many rounds as possible (AMRAP) within 20 minutes. See more at FitnessRx for Women!