Throwitdown wrote:
Avg heart rate was 165 according to my watch.. Not sure if that tells anything or not.. Or if that was accurate ... I'm still learning about heart rate(s).
If you are following Pfitzinger's 18/70 plan, he has an entire section on heart rate pacing in that book! (Advanced Marathoning). Read that section!
I don't think you have measured your max heart rate properly. My max is 180BPM, and resting is 46BPM, so you'd think our HR zones would be similar. However that same book says my tempo range is the low 160's. I find it hard to believe that you can hold tempo pace for 1:45+. Tempo pace is defined as your race pace for an hour long race. After 30-40 minutes at this heart rate zone, you should feel pretty tired, but like you could have hung on for a couple more miles. Not 10 more.
It's probably too late to worry about heart rate pacing as you are likely to just mislead yourself (again).
Pacing a marathon properly is more of an art than a science, compared to other race distances. It takes a lot of experience running to race one properly. If you want to be cautious, do the 10K tune up race (which is in your plan), go to the McMillan running calculator (google it) to find your equivalent race time for the marathon, and then add 5-10 minutes to that time. Head out at that marathon pace for the first 20 miles, then pick it up if you feel like you can.