Murakami started running in the early 1980s and since then has competed in over twenty marathons and an ultramarathon.
Kawauchi is a frequent competitor, entering many races each year, ranging in distance from the 1500 m to the 50 km ultramarathon.
He decided to attempt to set a record as the first person to run around the world, an extreme ultramarathon feat.
The race is billed as the toughest ultramarathon in the world where the temperatures can drop to -50 degrees plus wind chill.
There's an eligibility criteria for the participation in this extreme ultramarathon.
In 2011, 84 km ultramarathon was replaced with 100 km ultramarathon.
The island is known for marine turtles and traditional music, as well as its ultramarathon and its sand dunes and beaches.
Having to ride continuously for days with little to no sleep puts this event in the ultramarathon category.
