Found this in my online journal from about a year ago. I include it here as an example of what "family fitness" can look like:

Today, after a short bike ride on the American Tobacco Trail in Durham, NC (the exciting part was that we found it at all, thanks in part to Google Earth and some dumb luck), my kids and I and family friends hung out at the park. We played frisbee, spotted the kids on the monkey bars, and sat around and talked.

My buddy Rafy and I also did a short circuit on the playground. Chinups on the swingset (the kids were impressed and they worked on their own sets on the monkey bars). The equipment at your average playground can really kick your butt, if you're half motivated and know what you're doing. (Important disclaimer: the serious body weight stuff you can do at the playground can be dangerous if you don't develop correct alignment and sufficient strength with "assisted" activities.)

And my kids love to see me get my butt kicked. Not only that, but I often find them trying the same activities themselves. It's a funny and virtuous cycle - I mimic them playing around and being active and challenging themselves physically, and as they grow they think that it's normal for grownups to act that way. So they do pullups and wall dogs and rope skipping to be like me.

When it comes to workouts, if it ain't fun, how long am I going to "stick with the program"? And if I can't do it with my kids, when am I going to find the time on a consistent basis?