text: whats the best work out for a marathon?   you should start at least 20 weeks out with a schedule of running that builds up to longer and longer distances.  here's some links to marathon training guides, with complete schedules for beginners and advanced runners.  http://www.stlouismarathon.com/event_details/training_guide.asp http://www.fleetfeetstl.com/training_plans.htm