Responsive shoes inspired by progressive running design. What's new? What's next? These men's Reebok Zig Dynamica Running Shoes in Cold Grey represent the future of running-inspired design. A breathable mesh upper rides on a lightweight FuelFoam midsole that offers heel-to-toe comfort and responsiveness from step in to step out. The bold zigzag midsole design stands out as distinctively Reebok. Mesh upper with Breathable feel and Responsive FuelFoam midsole.