How To: Avoid damaging my knee when training for and running a marathon

The best way to get injured with marathon training is to not have a solid running base. Slowly increase your mileage by increasing duration / distance NOT intensity. Your training should mirror the race your planning to run. Any training plan worth its salt will give you a recommend base. Hal Higdon's http://www.halhigdon.com/marathon/Mar00novice.htm recommends: but ideally before starting a marathon program, you should have been running about a year. You should be able to comfortably run distances between 3 and 6 miles. You should be training 3-5 days a week, averaging 15-25 miles a week. You should have run an occasional 5-K or 10-K race. It is possible to run a marathon with less of a training base (particularly if you come from another sport), but the higher your fitness level, the easier this 18-week program will be. A good book is Pfitzinger's Advanced Marathoning (don't let the title scare you). It has a lot of the background info on how the plans were constructed, etc... In short: Run lots, have a good base, have proper shoes, and take care of your body.

You should find a local organization that has a marathon training class. It does many things for you: you get weekly feedback on how to improve, you will be motivated to do all the training and not take shortcuts, and you will set reasonable goals for yourself on how fast and how far you can run. Also IMHO you knees and back are balanced by core ("Stomach") when running. If you have too much weight there (like me) or don't do any sit-ups (the thin guys) you pay for it in other areas.