X-shaped Speedboard® From burpees to box jumps, take on all moves in total comfort with the X-shaped Speedboard®. Made with a pliable nylon blend for better forefoot flexibility during multi-lateral movements. More stable. More soft. The Helion™ superfoam midsole delivers cushioning underfoot, while extra padding in the heel means even more comfort. For lateral stability, the midfoot cage and star lacing system wrap securely around the foot. More sustainable steps The breathable mesh upper is made with at least 90% recycled polyester. As with many of our shoes, the upper's yarn is dope dyed – a process that requires 90% less water compared with standard dyeing techniques.