The Avi-Effort shoes from Avia are the first biomechanically precise toning shoes that allow your feet to move naturally, for comfortable, easy toning action with each step. This pair of shoes features: Synthetic and mesh upper is breathable, supportive and very lightweight. Padded collar, tongue and insole for comfort and a snug fit. Midsole with AVI-motion toning technology including Archrocker and Negative heel engineering, promotes muscle activation by mimicking the effect of walking on sand. Shear Cantilever System accelerates the heel area's ability to rebound to its natural state in time for the next heel strike. Forefoot grooves allow for natural dorsiflexion. Solid rubber outsole for excellent traction on a variety of surfaces. The time to get in shape is now, lace up a pair of Avi-Effort toning shoes from Avia and get started today.