Here is an interesting article on the psychology of running goals.
http://www.runnersworld.com/sports-psychology/round-number-times-for-marathonsHere is the study with lots of statistics.
http://faculty.chicagobooth.edu/devin.pope/research/pdf/Website_Marathons.pdfLots of interesting stuff is discussed including the potential to speed up or slow down based on goal expectations and how runners with slower times have more room to increase their speed. Interesting ideas to apply to other aspects of life.
