Richard Donovan began his pacey journey through 12 states on San Francisco’s Golden Gate Bridge on May 19 and, with about 800km, to go he is due to finish in New York on September 5.
Despite running up to 75km a day, the trip was not designed to set a new continental record but to train the former economist for an unprecedented run across Antarctica.
“People might think why run across the US to prepare for something in Antarctica but a lot of it is to do with the mental process you go through,” he said.
“The toughness and development is applicable to any climate. It’s all about toughening up and looking at distances in a different way.”
Donovan is in the record books since 2002 after becoming the first person to run a marathon at both the North and South Poles. He followed that feat by running seven marathons on seven continents in less than six days in 2009.
Donovan had his US route specially designed to go off the beaten track and take in epic sights as well as crippling endurance tests.
“Strangely, it was open range cattle that bothered me more than anything, which is funny,” he said.