The Greatest Running Shoe Never Sold

Late one night in August 1997, 54-year-old inventor Lenn Rockford Hann placed two bottles of Gatorade near Concourse F of Chicago O’Hare International Airport, unlaced his sneakers, removed his socks, then dodged curious maintenance workers for two hours while running 13.1 miles on the walkways. His pace surprised him. He was convinced the springy, resilient surface was almost perfect. “My legs felt amazing,” says Hann, a marathoner. “I’ve been chasing a shoe that feels that good ever since.”

For years, Hann had been designing a running shoe that he hoped would give him an edge. After his airport run (in the days of lighter security, naturally), he knew he was on to something, and he became obsessed with O’Hare’s movable sidewalks. Finding a walkway in the midst of repair on a subsequent jog, he jumped into the pit to look at its clockworks. There he found rollers on each side, with nothing holding people up in the middle but the belt’s tension. The next day, Hann called the belt company, Dunlop Conveyor Belting, and learned they were tightened to 2,500 pounds to create the right bounce.