There is no greater glory for a man as long as he lives than that which he wins by his own hands and feet.
—Homer, The Odyssey
When Henry Ford first put his model T on the road in 1908 and ushered in the motor age, the track record for the mile stood at 4:15.6, the record for the shotput at 49 ft. 10 in. And that, the doom-criers felt, was about as fast as a man would manage to run and as far as he would throw the iron ball—in an age when the machine was taking over the work of human...