The following excerpt was taken from the book, 50/50: Secrets I Learned Running 50 Marathons in 50 Days–and How You Too Can Achieve Super Endurance! by Dean Karnazes on page 156:

“The key to keeping your passion for running strong over the long haul is to ensure that it remains a journey and never becomes a routine. Lots of runners, myself included, use running to test and redefine various physical and mental limits, which brings endless fulfillment. Others pursue intellectual development through running, learning ever more about the art and science of effective running, how nutrition affects performance, and so forth. The possibilities are endless. The only wrong to move is to miss out on all of them and make running something it’s not: boring. Because the simple act of putting one foot infront of the other and moving forward at an accelerated rate can be one of life’s greatest–and simplest–pleasures”