The most common question I get from people back home is: What's China like? My website: http://www.owendennis.com China blog: http://www.owendennis.com/blo...
Assuming you can run 2 miles now at a nice easy pace (conversational), within 20 weeks you should be able to train up to being able to finish marathon distance at that nice easy pace (between 10 and 12 minute miles) or approximately 4 to 5 hours.
Most experts say that two marathons should be the limit one should run per year (spaced six months apart). This rule applies both to the beginner and novice (regardless of marathon pace) along with the advanced runner who turns in a competitive (hard) effort.