I wish it was that easy.  I must say though, that when I try and watch what I eat and be good, my jeans always seem to fit better.  I wonder if we want is the to ability to control our perception of things and therefore affirm what we are trying to do.  These women may subconciously be altering their eating or exerting more effort when they do their jobs, so in truth be burning more calories. I still think the only way to keep trim and be heart healthy is to exercise and get your heartrate up.  Sorry, no easy anwers!