Determining the reasonableness of a refusal to treat: Scenario 1

A doctor is participating in a half-marathon road race and hoping to finish the race with a good time. As he approaches the crest of a hill he sees a competitor who had been struck by a car, lying on the side of the road. There is a group of race officials attending to the injured person. He slows down with his running, looks briefly at the scene, and then tells his running partner that the injured athlete looks alright, and they need not stop. They should still make a good time for the end of the race.
Did the doctor act ethically and legally? Why or why not?