I have only been running3-4 miles 3-4 nites a week. I have slowed down to 7.3 miles on my long week end runs. But my My feet burn so bad I have to stop and take off my shoes and walk barefoot for a few feet, then I run another 2-3 miles and repeat. So I am trying new shoes again, Brooks Beasts didn't work last week, So now Iam trying Axis Cumulas iii, that's one of the shoes that the people from roadrunner.com said may help. I superpronate or over pronate. I don't want to waite until next year to complete a offical Marathon, I have trained so hard for a year to be where Iam today..God help me here. Cecil.