Japan has a strong tradition of marathon running. The 1964 Tokyo Olympic Marathon was the first-ever to be broadcast live. In the 1980's and 90's Japan enjoyed a long period of success, but over recent years Japan's runners have struggled to keep pace with their East African rivals. A new project designed to improve performances will culminate in a one-off race to decide the Olympic marathon team later this year. We follow the efforts of Japan's marathon runners to get back on top of the world.