Do psychological stress and physical exercise elicit different plasma catecholamine responses in working subjects?
Physical exercise primarily activates the sympathetic nervous system (norepinephrine), while psychological stress primarily activates an adrenal response (epinephrine).
A technique was devised to monitor plasma catecholamines in a minimally obtrusive fashion in subjects going about their working activities. There was a disparity between plasma norepinephrine and epinephrine levels in different situations. During public speaking, epinephrine levels increase twofold, whereas during physical exercise, norepinephrine levels increase threefold. It seemed that while exercise induces a response of the sympathetic nervous system, psychological stress induces primarily an adrenal response. (JAMA243:340-342, 1980)
Joel E. Dimsdale (Fri,) studied this question.