Christi Taylor presents the Ultimate Cardio Core Workout! Whether you've worked out with Christi before or not, her expert cuing and unique ability to connect with her students will keep you on task and moving like a pro. The 35 minute cardio portion is followed by 20 minutes of intensive core training. A relaxing cool down and stretch segment wraps up your workout. Optional tools: 3 to 5 pound medicine ball, step.