20 week marathon plan for experienced marathon runners who are looking to PR while staying healthy. Pre-requisites: Successful completion of several marathon cycles within the past 3-5 years. Consistent training for the past 2-3 months. Free of injury. Currently tolerant of at least: (x4) 45-60 minute continuous runs per week plus a weekly long run of at least 10 miles. Prior experience with moderate and high intensity running sessions is required. What you get: Guided 20-week marathon ...