I just realized that I started running around the age of 13, that is 37 years of running! Initially it was a way to stay in shape for another sport I was focused on; until the age of 21 I played volleyball semi professionally and running was part of training. Later I just ran on regular basis to stay in shape until I was 38 when I picked up Triathlon, at which point running was the sport.
Now, again, running is a way to stay in shape and support my battle with cancer. Ashley Marcin lists in this article few other ways to measure your running success.
Photo credit: João Lavinha / Foter / CC BY