I've always considered keeping fit as good stewardship of our bodies, temples of the Holy Ghost. As long as it doesn't become an issue of vanity, it's certainly important for one's health. That said, I never need to go out and "exercise", as I am extremely active and running up and down hills moving sheep, hauling hay bales, carrying lambs, milking, mucking, setting up fences, pasture walking, etc. provide plenty of exercise. As a chronic insomniac, I can often only sleep if I am completely worn out physically. Most people do not have such opportunities.
This.
I also sleep best if a get a certain minimum of exercise -- enough to wear me out a bit, or at least take the edge off my energy.
And this whole thread illustrates that the modern lifestyle is a problem. Sitting in front of a computer all day is NOT sufficient to take basic care of one's body (maintain ideal weight, keep heart in good shape, etc.)
So many people have office or "white collar" jobs. I'm one of them. That's why I moved to the country so I could do more things outside. When you live on a city plot, it's too easy to stay inside all the time. Unless you obsess about your landscaping or have a small garden, there's simply nothing to do outside. (Barring a few sports in your backyard or something like that). You can drive somewhere, but how often are you really going to do that? Are you going to get in the car EVERY DAY? Even cycling is optional -- it doesn't HAVE to be done so it's easy to skip it.
Let's put it this way -- I do lawn care for my mother-in-law. She actually has several "yards" that add up to a good part of an acre. I use the riding mower, then a push mower, and finally a weedwhacker. It takes about 2 to 2 1/2 hours to do the whole thing. Her yard looks gorgeous when I'm done! I enjoy doing it because I can make it so clean in just a couple hours. Here, I have to spend a couple hours every day for a week -- and I'm still not "done".
If I lived in a house like that, I'd simply have a LOT less to do outside. I know that for a fact, because I used to own a house in the city for about 3 1/2 years.
In that 3 1/2 years I removed every non-productive tree & bush by hand (no chainsaw), had a big garden every year, planted a half-dozen fruit trees, dug a huge pit for compost, etc. By the time we moved, I had run out of stuff to do! In fact, I had my eye set on my next-door-neighbor's huge oak tree. I was actually VERY tempted to declare war (as it were) and start trimming the branches that hung over my property line. She (the next-door neighbor) would have hated me. It's probably good that we moved when we did! :)