I started out with a six day a week plan, but cut that to 5. I needed more rest or my legs were cooked. I followed my plan faithfully initially for the first half, but discovered that the drive to get a specific number of miles on a certain day over a certain type of course was draining the fun out of it for me.

Make sure you progress your mileage every weekend and do a hilly course once a week and you should do fine.