I had a horrible run yesterday. I set out to do 11 miles and ended up walking almost the entire last 3 miles of it. It would be easy to blame it on the heat (already past 80 degrees when we started at 7:30 am) but that wasn't it. The Greenway was packed with runners, each pushing forward through air so thick it literally felt like it was pushing you back. No, for me, if was a combination of factors that included: 

• Barely drinking any water the day before the run
• Not eating a proper meal the night before the run
• Heading out too fast in the initial miles