the current record of two hours is held by the ken yan. the sub two-hour marathon, the sub frontier. >> first way to start is providing your weight and height. >> this is nike sports research lab. it is a rare chance to step inside. in a few minutes, they're going to put me to the test to see how i stack up against three athletes, nike identified for this record breaking attempt. it started largely. >> how audacious is this? >> i think it is enormous from a encycloped psychological barrier.