Why?

I ran outside in the park tonight, risking the last minutes of my workout being in the dark; pushing the limits of daylight preferable to running my scheduled intervals on the treadmill again. It feels like I have been doing too much of my hard running on the treadmill lately, as tonight it felt tough to pick my feet up and lift my knees to get my turnover to match how fast I wanted my legs to run. Running hard on the treadmill still counts, I think, because I'm still moving my legs and my heart's doing the work too, but keeping up with the belt moving below and powering my pace on the pavement myself are two very different feelings. It was also quite chilly, the "feels like" being in the mid-20s and once the sun disappeared behind the line of forest nearby, "feels like" began to feel even colder, which did not help my tiring legs churning as they tried to dip below 7-minute pace. By the end, my hands were burning with cold even tucked in their gloves, which was distracting and uncomfortable.

The cold kept the population at the park down, but a couple times I passed a dad and his very young son walking their equally-young dog. When I was in the midst of my second 1200m interval, the little boy asked me, "Why do you run?", dragging out the last word so it sounded like "ruuuh-uhhhn?" I was well past him before I came up with an answer I never got to tell him:

Because I want to.
Because I can.