Description:Designed for the biomechanically efficient runner, the Gravity lightweight performance trainer offers a fast, flexible ride with incredible energy return and shock absorption. It features Newton’s Action/Reaction Technology™ in the forefoot and an advanced rearfoot design aimed at maximizing forward propulsion and optimal running form. Independent studies prove this technology, in conjunction with the LAND-LEVER-LIFT running technique, provides less stress on a runner’s joints, muscles and tendons. With improved durability in the heel, a new high-rebound midsole material and improved upperfit, this shoe will keep you running faster and farther with less injury and quicker recovery. UPPER * Highly breathable, fast-drying,open air mesh * Minimal anatomical forefoot support strapping * Biolateral stretch panels for comfort and fit MIDSOLE * High-rebound light-weight midsole offers firm cushioning * Biomechanical forefoot plate and flex grooves to increase communication (proprioception) between foot and the ground OUTERSOLE * Carbon rubber heel for increase durabililty * Rearfoot technology cradles the heel as the foot settles for protection and cushion * Forefoot Action/Reaction Technlogy