This plan is for the intermediate marathoner who routinely trains 6 days a week and up to 50-60 miles a week.This plan is focused on 6 runs a week. . The threshold workouts should be done on flat ground. I have given the option of 5 long runs that are 20-21 miles. 3 are planned easy runs of 20-21 and 2 you have the option of going 18-20 on a workout day long run. You should have at least 4 weeks of base training under you before starting this plan and be close to 60 miles a week! I did not ...