Due to the extreme flex and compliant nature of the Free sole technology, the Free RN mimics the experience of barefoot running since the foot is allowed to flex naturally with the ground topography.
According to Nike, the Free line was developed after learning that Stanford athletes were trading barefoot on the golf course.
Therefore the flex of the sole has been designed to specifically mimic the biomechanics of a barefoot running experience.
The result is a shoe that feels natural on the feet and and is a joy to run in. I tested the Free RN on different surfaces, including forest, basic trail, and asphalt.