Count a PR on a race which seemed to be measured too short? (Read 1854 times)

I'd measure the course with my bicycle, which I know to be as well-calibrated as I can get without USATF certification. It's more accurate than my Forerunner for sure. And then adjust accordingly.

The funny thing about PR's is the "P" - Personal. So, everyone does it a little differently. But, in the end, it's what the time tells you about your level of fitness that counts. It's a tool that you can use to adjust your training accordingly. Since you're actually training for a marathon, if I understood that correctly, then try to analyze the result in that regard and move on from there.