Flash forward to today and your average adult (and kid) stays inside almost 24/7. Even more ironic is the fact that what we used to do-play (we now call it "exercise") is now defined as work (sounds negative eh-who wants to do more work?).
The take home - get your butt outside - go to your local park, almost all of them have pull-up bars, dip stations, balance beams and the like to get a great "workout" in without all of the electrical pollution and stuffiness of your average gym. Take a month (or two) and view your workout as play, like we did when we were kids.