F-R-Thundercat and Daeve,
Thanks for the fresh comments. I'd like to blame humidity, hydration and a whole host of other factors but I feel like I would just be making excuses for myself when the truth of the matter is the endurance wasn't there. I had a good breakfast and had loads to drink and 6 jelly babies at the start line!
The 10-13mile runs were due to time constraints - I didn't have the time to go above this. I have run more than this in the past and will again when possible, if I can drag myself back out there.
I did do one very hard plyometrics session on the Tuesday night before the race which left me pretty sore until Friday - maybe if I had skipped this I would have had that little bit extra on the day. We'll never know.
I've followed Hal Higdon's plans for marathons in the past but for this next one I thought I would try and run 6 days a week - 5 weekdays with one speed session, one recovery session and 3 easy days for mileage, then a long run at the weekend. In addition I do plyometrics/weights once a week as well so I'll continue with this. I'm hoping to get my mileage up sufficiently that my endurance can't be called into question again but do you think that this is sufficient not to get slower?
I need to do something differently to before. I just haven't decided what.