The wide, flat heel becomes even more stable with an inner plate that distributes weight from edge to edge. It is also pliable to make it comfortable for cardio intervals. Nike React foam provides a comfortable, cushioned base that feels light and bouncy when you kick it into high gear for cardio and sprints. Redesigned rubber wraps around your arch for intense grip while rope climbing. Rubber tread gives you traction from the training room floor to the pavement. Lightweight mesh with textured overlays in high-wear areas helps keep your foot cool without sacrificing durability. The tab locks the laces with a Velcro fastener to keep them out of the way.