I'm active too. I fence, play tennis, and take dance (on occasion). I even go to the gym a couple times a week for weight training. Yet, it isn't a driving, natural inclination for me. I just know the healthier my body is, the more efficiently my mind works. Being as healthy as I can be, is like insurance. It puts my mind at ease. Vanity plays part too.
Nevertheless, it's usually wrapped up in a strange dichotomy. For example, I realize the ritual of marriage is an antiquated method that isn't necessary in this day and age. Yet, I think it's revolting when people violate the positive attributes it represents.