The Nike Free Run+ is the latest version of Nike free-running footwear. It is designed as a training tool to mimic the foot’s natural motion while delivering cushioning, traction and protection from the elements. More than 35 years of research in the Nike Sport Research Lab, combined with feedback from elite athletes, have helped Nike to develop the Free technology, which strengthens the muscles of your feet—ultimately leading to a more efficient workout. "It's the next best thing to being barefoot," Oprah says. "It weighs next to nothing."