Spinervals Flexible Warrior 3.0 - Flexibility for Swim, Bike, Run Increase your range of motion and total body flexibility. Speed recover, prevent injury and enhance performance. Incorporate the Flexible Warrior Athletic Yoga stretch routines into your off season recover phase and race season competition to take your performance to the next level. Karen Dubs coaches six competitive triathletes through four short and effective yoga stretch routines designed specifically for multi sport athletes. Karen Dubs is a Registered Yoga Teacher and ACE Certified fitness professional with over 15 years teaching experience.