There is no such thing as running a marathon without "proper"
training.
As a skier being in pretty good shape anyway, the bulk of my thirty years of running at least one marathon a year have been on less than 100 miles running for the entire year and many less than 50 (including the marathon).
A rule of thumb in the early days was being able to run 13 miles, no matter how slowly, without stopping, even less than a week before, was sufficient evidence of running the full 26.2 miles and I proved it many, many times.
It can even be done after swimming 2.4 miles and cycling for 112 by people who have never run a single race of any kind in the whole life (to say nothing having only swum less than a mile in the last 20 years and never ridden a bike father than 20 miles at one time), . . . but that was back in the days when we didn't know we were supposed to train!
There is such a thing as running a marathon w/o honoring a pace commesurate with the runner's condition.
Unfortunately, it's too bad most people are afraid of slow running, getting last place, etc.
http://This message has been edited by Tetsujin30 (edited Sep-22-2007).