The wide, flat heel gets even more stable with an inner plate that distributes weight from edge to edge. It also flexes to make it comfortable for cardio intervals. Nike React foam makes a comfortable, cushioned base that feels lightweight and springy when you kick it into high gear for cardio and sprints. Revamped rubber wraps up your arch for intense grip during rope climbs. 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. Tab locks down the laces with a hook-and-loop closure to keep them out of the way. Handstand clip at the heel minimizes drag during wall exercises. Flywire cables integrate with the laces to secure your midfoot. Grooves in the sole let your forefoot bend naturally.