Seems to, at least the fatness of the population varies.

What I noticed, living in Colorado versus Texas, is that the people in general in Colorado were more fit, it wasn't just bike riders. I think the major part of that is that the climate is more pleasant for exercise. Having mountains to hike in helps, too.

One of my coworkers from Colorado spent a week in Alabama. His account, "I jogged to the end of the block and I was already soaked in sweat. no wonder everyone's fat down here! It's too hot to exercise!"