The goal of the Reebok CrossFit Nano Speed is to provide a sturdy, flexible, supportive, flat soled running trainer that lives up to the CrossFit badge. The Reebok CrossFit Nano Speed exceeds our goal. By building a stable low profile midsole for lifting and moving heavy loads, this training shoe provides a responsive running platform. By building a full protective outsole with built-in Metasplit grooves, you get greater traction and flexibility. Creating a mid-foot DuraCage to keep you on the platform, overlays are eliminated for increased forefoot comfort and response. There are plenty of running shoes that you can do CrossFit in, but we made the FIRST CrossFit shoe that you can run in.