I did a 140.6 late last September, then did the JFK 50 mile run mid November. I then started the Pfitz 18/70 (or whatever number it is in the 70’s), got to week 12 and then got blasted by some hamstring tendonitis. In saying that, my stand alone marathon PR is 3:37 on a super hilly Charlottesville course. My hamstring injury popped up in March, I kept in gentle until June and then still had the base to run a 38:XX 10K which was a PR. It’s crazy the shape that the 18/70 program gets you in. The only downfall was I was training for an April marathon at the time so a lot of my runs were in the dark before work or in the dark after work because of day light savings time. That was my only gripe. I’m not sure if 70 miles a week was just too much for my legs to take and that perhaps I should try the 18/55 program next or if my legs just weren’t rested after doing a 140.6 and 50 mile ultra less than 2 months after each other and then starting marathon training a month later. I’m betting on the legs not being healed up. I’m still a little apprehensive about putting in too many miles, but my running is at 40 miles a week right now for Ironman Florida with no pain.
Again, the Pfitz training program is amazing! You will be in a super shape. Make sure you buy the book too because he goes into detail as to what you are to accomplish on each run. Also I was thinking of possibly doing the 70 mile a week program but putting in a bike ride and swim on the recovery run days. I can get a more intense workout and take a little pounding off the legs. I think that would be a good substitute.