Coach Jeff ROC wrote:
Pete Pfitzinger's Advanced Marathoning 55 mpw plan and subtract 15%-20% from each run.
That's a good plan, although OP specified 50-minute max on weekdays, which makes Pfitzinger's medium-long runs difficult to schedule.
Also, and I may be a lone wolf on this, but while reducing the total mileage of a plan, I would keep the long-run distances. Even if I had to run slower than Pfitzinger's suggested paces.
My experience has always been a big pay-back from single, long-duration efforts -- no matter the pace. I know others often make a point of keeping the long run at some arbitrary maximum of weekly mileage, but I don't buy into that notion.