"I've been passed by wheelchair racers when I'm running," he said.
Included in this were two disability athletics events for wheelchair racers.
Bottom line, wheelchair racers just don't like getting beat.
Nine of the world's top wheelchair racers due to take part have best times up to 18 minutes inside the restriction.
Rosenthal had volunteered in 1991 and 1992 to guide the wheelchair racers.
They also promised not to deflect news media attention from the wheelchair racers and to let them cross the finish line like everyone else.
But wheelchair racers must contend with certain vulnerabilities while training on the roads.
That first race began on a cold day with 57 runners and one wheelchair racer.
It attracted more than 35,000 men, women and wheelchair racers.
Keith did not own a sports chair, a lightweight but expensive version needed by wheelchair racers.