The Men's SB50 Nike Free Trainer 5.0 V6 AMP (NFL) Training Shoes features hexagonal flex grooves and rubber pods in high-wear areas for an incredibly natural feel and durability where it counts. Lightweight Flywire cables integrate with the laces to lock down the foot and give you an adaptive fit during multi-sport workouts.FLEXIBLE STRENGTH. DYNAMIC FIT.
After 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.