Why? Because I want to stay fit, healthy, be an example for my kids, and achieve a goal of running in the 2:30s. I figure I've run in the 2:teens, 2:20s, and 2:40s, so I gotta try to hit my new goal before Father Time continues to slow me down. It's good to continue to set goals as you age. Otherwise we'd let ourselves go to sh!t in our mid-30s. :)