FLEXIBLE AND CUSHIONED The Nike Free Train Instinct Men's Training Shoe gives you the flexibility and comfort you need for intense and varied workouts. A dual-density midsole adapts easily to cardio or lifting while a revolutionary Nike Free outsole expands and contracts with your foot on every landing. Dynamic StrengthThe breathable warp knit upper offers multidirectional stretch and incredible durability, letting you move freely and confidently during tough workouts. Stable CushioningThe shoe's unique dual-density midsole provides the cushioning you need for cardio workouts along with the stability required for lifting. Dynamic MovementWith each stride, the updated Nike Free outsole's unique tri-star structure expands and contracts in all directions, following the natural motion of your foot. More Details • Flexible collar creates offers stability and support at the ankle • Knit outrigger in the forefoot gives you lateral stability as you cut • Solid rubber outsole with aggressive traction delivers excellent grip 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. The team spent eight years studying the biomechanics of runners' feet in motion. 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.