After viewing athletes training barefoot in 2002, Nike set out to develop an athletic shoe that would feel more natural and weightless, simulating barefoot running. Nike Free is a shoe that allows the muscles in the foot to gain strength by providing less constriction. Designed to allow feet to move more naturally and freely, building strength over time. It was introduced in 2004 after Nike representatives observed Nike sponsored track athletes training barefoot. Nike Free shoes are specifically designed to let your feet move more naturally and freely than traditional athletic shoes. Over time, this helps make your feet stronger. But because you'll be using some muscles in your feet more than you might be used to, it may take some time for them to get used to all that freedom. To give your feet time to adapt, we recommend you transition into using your Nike Free footwear gradually.