adidas Adizero Takumi Ren Boost 3 Running Shoes - SS15 SPRINTFRAME Construction - Provides stability and speed through geometrical research to create a lightweight and supportive running chassis. Extended TORSION SYSTEM - For energy return in the forefoot and natural integrity in the midfoot. ADIPRENE - Under the heel for superior cushioning at impact. Boost - In the forefoot maintains propulsion and efficiency. QUICKSTRIKE Outsole - Decreases weight and increases flexibility and durability.