This has not escaped the notice of scientists who have been studying the effect. I notice this when I take a walk during lunchtime. It is short walk of about 15 to 20 minutes, but during the trip out, I think this is a long walk, and on the way back I seem to return right away. I am wondering if a reluctance to return to work is a factor. The scientists did not seem to have considered this factor. People who are taking a trip might be eager to get there and not quite as eager to return home.