- Reebok Unisex' Energen Tech Shoes VERSATILE RUNNING SHOES FROM REEBOK'S [REE]CYCLED COLLECTION From the morning run through to the rest of your day, the energen tech keeps you comfortable with its cushioning fuelfoam midsole. The overlays on the upper provide targeted support where you need it most, and a rubber grip outsole lets you stride confidently in all conditions.