Mills GRIT – CARDIO is designed to burn calories and rapidly improve athletic prowess and efficiency. The workout combines high-impact cardio training with functional upper and lower body exercises. GRIT CARDIO is an unparalleled and comprehensive high-intensity workout that helps you to improve your athletic characteristics and general condition in record-time. GRIT CARDIO as well as crushingly efficient HIIT workouts will blow your calorie expenditure through the roof, and you’ll continue to burn calories even long after the workout. Ready, set, go!