There is a lot of satisfaction in that. I slept and dreamed that life was all joy. I awoke and found that life was all but service. I served and discovered that service was joy. No doubt a brain and some shoes are essential for marathon success, although if it comes down to a choice, pick the shoes.
More people finish marathons with no brains than with no shoes.
Because I can. No matter what hurts at the beginning, by the end of the race something else will hurt worse. Pain is good. Heaven is under our feet as well as over our heads. It's not the beginning or the end of a race that counts, it's what happend in between.