EVERYDAY NATURAL FLEXIBILITY
More flexible than the 5.0 and more cushioned than the 3.0, the Nike Free 4.0 Men's Running Shoe unleashes your natural stride with a lightweight, supportive upper and a highly flexible, low-profile outsole.
The woven mesh upper features no-sew overlays on the midfoot for lightweight support and a locked-down feel.
New hexagonal flex grooves are hot-knife cut into the outsole and wrap around the sidewall so your foot moves more naturally in every direction. Secondary cuts intersect the flex grooves, adding even more flexibility.
The heel mimics the shape of the foot, rolling with the ground to promote a more natural footstrike.
With a 6mm difference between heel and forefoot height, the Nike Free 4.0 gets you closer to the ground for a more natural feel while still offering a great blend of cushioning and support.
Minimal sockliner molds to your foot's curvature for added support and comfort
Non-stretch, knit-in heel for structure and support
Asymmetrical lacing for reduced lace pressure on the top of your foot
Waffle outsole lugs help absorb impact and add responsiveness
Nike Free Origins
After learning that Stanford athletes had been training barefoot on the university's go-lf course, three of Nike's most innovative and creative employees set out to develop a shoe that felt natural and weightless, similar to bare feet. In 2002, they examined a group of men and women with pressure measuring insoles taped to their feet, using high-speed cameras to capture images of each foot in motion.
The team spent eight years studying the biomechanics of shoeless running. The results yielded a profound understanding of the foot's natural landing angle, pressure and toe position, allowing Nike designers to build an unconventional and flexible running shoe from the inside out. Since Nike Free's introduction, millions of runners have trained in the shoe, including some of Kenya's world-class runners.