Just re-read a great article about the iron mind entitled, The Iron, written by Henry Rollins (originally published in 1993 in DETAILS Magazine). If you've never read it, or would like some insight on why a strong body and mind go hand-in-hand, read it here.
It took me years to fully appreciate the value of the lessons I have learned from the Iron. I used to think that it was my adversary, that I was trying to lift that which does not want to be lifted. I was wrong. When the Iron doesn't want to come off the mat, it's the kindest thing it can do for you. If it flew up and went through the ceiling, it wouldn't teach you anything. That's the way the Iron talks to you. It tells you that the material you work with is that which you will come to resemble. That which you work against will always work against you. - Henry Rollins