Once you take a few strides in the Nike Alphafly 2, you'll never look at your favorite pair of old racing shoes the same way again. These rocket ships are made to help shave precious time off your personal records without surrendering the foundation you need to go the full distance. A thick, lightweight support system marries the 2 worlds of comfort and speed in holy running matrimony. Enjoy the greatest energy return of all our racing shoes while you chase your personal bests and leave the competition in the dust.