This plan is for the runner without an extensive running history who needs to increase their aerobic capacity (raise their aerobic threshold heart rate and pace). For more information on this read this article. You should be capable of comfortably starting off with 4 hours of low intensity running per week. The plan includes a strength program which we have found to be very beneficial for trail runner. The first 4 weeks are for familiarization and general conditioning. In week 5 begins what is the meat of the program our well proven muscular endurance sessions coupled with hill sprints to build running special leg power. The final phase of the plan drops the muscular endurance work and shifts to more running specific intensity.