Several years ago, we purchased an audio book, "Younger Next Year" (http://www.youngernextyear.com/) and it changed the way we looked at exercising and eating right. I can't say that we have been following the book's advice consistently over the years; it seemed making a living and other commitments always got in the way. Now that we're retired, no more excuses. There are two basic rules (1) exercise an hour every day (the book says it's a primitive need, something to do with gathering nuts or hunting) and (2) stop eating crap.
With such spectacular places to hike every where we stay, the exercise is something we look forward to every day; but eating right has been a challenge. We're working on that.