Agile But the nimble Dynafit Ultra 100 GTX trail running shoe got us through the finish line quickly. This pair is made using Dynafit's Heel Preloader construction wraps around the heel, allowing movement without displacement while Ghillie lacing helps keep your foot planted on a cushioned platform and the maximum volume fit gives our legs the opportunity to swell when we run miles. . No matter what we walk on Sticky Vibram lugs capture our impacts and breaks, ensuring that energy will not be wasted and the breathable GORE-TEX membrane protects against water and dirt so our feet don't get cut or blistered.