How beneficial is running a 100 mile race to my college application?

I get a composite score of 35 on my act, I volunteer, have taken numerous AP classes, and have a strong, but not perfect, gpa; otherwise though, im just like every other applicant. I'm planning on running the pine to palm in september, given that I finish, do you think that accomplishment will make me stand out? I'm planning on writing about the event/ training in my application essays, are there any other ways I could garner attention to what I will have done?