The Adidas UltraBoost 21 Men’s trainer is the latest in a long line to use boost™ technology. With no EVA, the midsole is entirely constructed from boost™, giving you the ultimate in cushioning and energy return. The new Torsion System provides a 15% increase in forefoot bending stiffness for a much more responsive run. The shoe is made with Primeblue, a high-performance recycled material made in part with Parley Ocean Plastic. 50% of the upper is textile, 75% of the textile is Primeblue Stretchweb also compliments this by allowing boost™ to move and adapt, expanding with the foot and with no restrictions. The heel counter is softer and opened up slightly around the achilles for a more natural feel and movement, but without compromising on its support.