“Lesson One: Stay off the elevator. Instead of riding the elevator at work or in your apartment building, use the stairs. There’s a reason stair-climbing machines are popular—it’s because walking up the stairs is good exercise. Find a well-maintained flight of stairs and frequent it.

“Lesson Two: Nearby parking is for sissies. By the time you’ve circled the Wal-Mart parking lot three times looking for the closest space, you could have parked way out on the perimeter and walked to the door already—while benefiting from some good activity. Next time you’re at the movie theater or the mall or the grocery store, forget waiting. Park as far away as you can and walk the distance. No one else will be out there, so at the least you’ll get fewer door dings.” (>>)