Just ran Scotiabank Toronto Waterfront. I have a half-marathon of 73 and was hoping for a 2:34. Felt great through 15.5, my half was 76:30, but started to unravel after that. I finished with a 2:43:50. Any ideas why there wasn't much correlation between half-marathon and full. I know all the variables (food, sleep, etc.) play into it but considering I felt even somewhat rested and prepared I thought cracking the 2:40s would be no problem. any ideas?