From Runner's World, common sense 10 Principles of Marathon Training:
A marathon training program can survive any challenge — as long as your determination remains strong. Here are 10 principles to carry you through your training.
From my four and seven-year-old cousins when I told them I was going to run the NYC Marathon:
Cousins: How far is a marathon?
Meg: How far do you think it is?
C: Ten miles?
M: Guess again.
C: 20 miles?
M: More than that, keep guessing.
C: 300 miles?!
M: Oh no, not 300. Only 26 miles. But still, that's like four hours of running non-stop!
C (McKenna): Oh, that's not so bad. That's only sixty minutes. Plus sixty minutes. Plus sixty minutes. Plus sixty minutes.
And she's right. I know I can run sixty minutes. Now I'll just do it four times in a row.