The runners’ time were clocked daily. All runners started at the same time and they had to reach a designated checkpoint. As each runner crossed the checkpoint, his time was logged. Each day’s time was added to the last. The fastest cumulative time would win the race.

Runners who failed to reach the checkpoint by midnight were disqualified.

"One afternoon, when 32 miles from the next station, I decided that I was through and climbed into an official bus and reported to Pyle that I was checking out. He sent me to the doctor who looked me over and treated my blisters and told me I'd be fit to resume the next morning. When morning came, I did feel some better. The bus took me back the 32 miles and dropped me off and I started again. I couldn't run. But I shuffled. I figured my pace to carry me the [previous day's] 32 miles and [this] day's 25 miles. That's how it happened that I was so far behind...If you have day's run of 25 miles and quit at three in the afternoon with five miles to go, your time goes on to midnight and to that is added the time it takes you the next day to cover the five miles." -Frank Johnson #155, interview in the St. Louis Post Dispatch, April 5, 1928.

Initially, runners were allowed to go back to where they quit for the night and try again. Keeping track became too complicated.