https://infogalactic.com/info/Kennedy_march
> A Kennedy march is a long-distance march of 50 miles (80 km), named after former American president John F. Kennedy.
> John F. Kennedy came into the Presidential office with a goal of improving the health of the nation as part of his New Frontier. As President-elect, he wrote and had published an article in Sports Illustrated, December 26, 1960, called The Soft American which warned against the negative aspects becoming unfit in a changing world where automation and increased leisure time replaced the benefits of exercise and hard work.
> The idea of the march developed from Kennedy's discovery in late 1962 of an executive order from Theodore Roosevelt challenging U.S. Marine officers to finish 50 miles (80 km) in twenty hours.
> The Kennedy march became a fad in the UK shortly after American people took up Kennedy's challenge. After Dutch television showed images of the Kennedy march craze, some Dutch people decided to make an attempt at finishing the 80 kilometers within 20 hours.
