Chad is a junior psychology major who is participating in a psychology experiment on exercise habits in order to receive extra credit for a class. When he arrives to participate in the experiment, he is asked to run in place for a minute. He is asked to do this three times. What he doesn't know is that his friend Larry, who is also participating in the study, is in the adjoining room being asked to run in place, too. Larry is hooked up to a heart monitor that measures his heart rate as he runs in place. It is likely that Chad is in the _____ control group.