Without fail, I hit a wall at Mile 18.
I realized it during last Saturday's long run. During races and training runs, Mile 18 is usually the hardest and everything after that mile is a huge struggle. By then, I think my brain has communicated to the rest of my body that it's been running on Gatorade and Gu for the last three hours and that it's in pain. I have a few long runs left, so I'm going to work on running evenly before mile 18 and pushing through the last few miles of my runs.
Monday: 30 minute interval run
Wednesday: 7 miles
Thursday: 6 miles
Saturday: 20 miles