FLEXIBLE AND QUICK The Nike Free Trainer 3.0 V4 Men's Training Shoe is designed for flexible natural motion and lateral stability. A dynamic knit upper molds to your foot for a locked-down feel and exceptional comfort in the gym or on the field. Stability and CushioningFlywire cables deliver stability and an locked-down fit when running, cutting, lifting or jumping. The Phylite midsole doubles as an outsole, providing resilient cushioning while dramatically reducing the shoe's overall weight. Lateral Strength and DurabilityA woven mesh and synthetic upper wraps your foot for enhanced lateral strength. No-sew overlays in key areas add the durability needed for intense training. Natural MovementHexagonal flex grooves and a rounded, anatomical heel combine for ultimate flexibility, allowing your foot to move naturally. More Details • Abrasion-resistant rubber outsole reinforcements enhance durability in high-wear areas • Internal heel counter helps control foot motion • Rounded heel promotes natural movement Nike Free OriginsAfter learning that Stanford athletes had been training barefoot on the university's golf 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.