Cloudwaveconsists of a redesigned elastic, thermal plastic wave running from the heel to the midfoot, creating an incredibly springy and well-cushioned ride.U4icX full-length midsole is a lighter, more cushioned version of U4ic that delivers increased responsiveness with a soft, pillowy underfoot feel.Smooth Rideis a gender specific network of grooves that minimizes the rapid acceleration and deceleration of the foot to create a smooth heel to toe ride. The Mizuno Wave Sky is a highly cushioned premium running shoe. It is best suited for daily training over any distance.