A hybrid hiking shoe that borrows from trail running technologies, the X Ultra 4 GTX® is the result of in-depth biomechanical studies aimed at delivering better stability to prevent ankle injuries. Research shows that 80 percent of hiking injuries are ankle sprains, and 95 percent of those are external ankle sprains. Using this information, Salomon identified key areas of the foot that needed protection and re-designed the X Ultra 4 to help guard against injuries.