I kind of like the first one, but I'd crop out the empty space on the left. Of course, you still can't see the main subject's face much.
The second one has the background well exposed, but the front of the runners is in shade making them under exposed. Also watch your backgrounds. Cluttered, especially with the course worker. It appears you have one entrant and two bandits.
The third one captures some agony. Got any showing the elation of running/finishing a marathon?