There's definitely a lot of psychological interplay with running and willpower/self discipline. I think I read somewhere that there are disproportionate number

There's definitely a lot of psychological interplay with running and willpower/self discipline. I think I read somewhere that there are disproportionate number of professionals/PhDs/otherwise successful people who are into ultra running, in part because they have the resources and flexibility needed for the training, but also because the ability to delay gratification and work towards a long term goal is required in both venues. On a more micro level, a good run can make the rest of life's challenges much less daunting...as I say to my wife: busy days seem a lot less overwhelming if you start them by dragging yourself out of a warm bed to run 8 miles in freezing rain.