Why is running so important to me?

 For the first couple of years that I ran the answer was pretty easy. Be a positive active role model for my daughter and get my unhealthy 230+ pound frame down into the healthy BMI range.For the past year or so though I know-in the back of my mind-that those reasons have changed.
My daughter loves to be active, she swims, she dances, she plays soccer and takes gymnastics. If I ask her to go for a walk she'll usually say yes. Our favorite activity this summer was taking our puppy to the soccer field and running around like crazy people. She told me a few months ago she's happy I'm not a "fat Mommy" like some of her friend's moms. I kind of feel like the mission has been accomplished as far as that's concerned.
So why am I still running? Why didn't I switch to some other activity that would keep me fit but take less time? Why do I run 6 days a week instead of the recommended minimum of 3?
Because, that little voice creeps in, you want to find your limits. I want to know just how far I can run, how hard I can push myself, because each time I think I've found my so-called limit I manage to accomplish it and know that I could go even further, a bit harder.
I guess you could call me a goal-oriented person. If I don't have a goal in my life it seems like I'm standing still, in neutral, going nowhere. When I was younger, when my life was about gaining an education to get a good career, those were my goals. Find something I love to do and make money doing it. Well it took a decade or so but I found the career that I truly love and get paid fairly to do it each day. Mission accomplished. But when I looked down at myself I found a physically weak person. Back in 2007 I knew that if I needed to, I couldn't run a block. I thought about those runners finishing the annual Ironman championships in Hawaii, seeing how they pushed themselves, their bodies, to their absolute limits and I wanted to know what that felt like. Thinking about how much better I would feel about my physical self was the seed that got me to lace up my 3 year old cross trainers and shuffle down that block over 5 years ago.
So here I am. I've finished a whack of 5 ks-I stopped counting a long time ago, 10 ks, half marathons and all distances in between. I thought the ultimate challenge was the marathon but after finishing it I knew I could not only do it again but go further than 42 km. I still run marathons, I enjoy the distance, but my new ultimate goal is 80 km, or 50 miles. I also know that is only a stepping stone to a 100 km attempt some time in my future. Barring injuries or drastic life changes I know I'll keep running and pushing to find my limits.