Adidas Response Boost Techfit Running Shoes Techfit Upper - Engineered for natural, flexible support and a seamless, sock-like fit. Energy Boost Midsole - energy-returning properties keep every step charged with an endless supply of light, fast energy. TORSION System - Distributes excellent stability in the midfoot. Mesh Overlay - Provides your feet with great ventilation whilst your run. Synthetic Underlays - Work in conjunction with the shoes lacing system to provide for secure snug fit.