Bi-Directional Movement With Marybeth Marotto This video provides vertical and lateral techniques in the water enhance core strengthening and promote increased flexibility. To access this content, you must purchase Bi-Directional Movement, OnDemand Monthly Subscription Payment Plan, OnDemand Annual Subscription, OnDemand Monthly Subscription, OnDemand 6-Month Subscription or OnDemand 2 Year Subscription or log in if you are a member.