The study tested students working in an imaginary call centre who were subject to abuse from clients.
Some of the participants were allowed to answer back, while others had to be polite and friendly all the time.
Those who stood up to clients had a rapid heartbeat for a brief period, but for those who had to remain friendly their heart was still racing long after the client had hung up.
The conclusion reached by the psychologists was that "being friendly against one's will causes nothing but stress".
So Stan Zemanek's not an arse-hole, he's just looking after his health.
