When my son ran Chicago in 2003, an Ohio gal collapsed at the end of the race and didn't make it. She was a physical fitness expert and was in peak condition.
Yesterday, Cleveland area high school cross country runners experienced problems, with medical attention required for some, and a later race or two actually cancelled.
I guarantee you cross country runners just prior to districts are in top condition.
So, I don't understand the comment about obesity. I think folks should respect long distance runners, in general, and marathoners in particular. It's not only tough to do but physically perilous in it's own fashion.
It requires courage, and courage shouldn't be mocked.