The first part of the experiment compared the relative reactivity of various cardiovascular measurements and self-reported assessment of mental arithmetic, an active coping stress task. It was found that the self-reported stress rating was more responsive (student's t = 9.4) than the physiological measurements. Among the cardiovascular indices, heart rate was the most responsive (student's t = 6.5), followed by the interval between R-wave and the maximal systolic pressure (student's t = 5.0). The second part of the study used a multiple regression to examine the cardiovascular components of change in stress rating following mental arithmetic. Both resting (psychophysiological "trait" variables) and change under stress (psychophysiological "state" variables) were used to predict change in stress rating. Stress rating increase were associated with greater maximal systolic pressure rate of rise (finger dP/dt) at baseline and less heart rate increase during mental arithmetic, yielding a multiple r of 0.67. The dual autonomic nature of active coping stress response is discussed. The shortcomings of using a correlate of a correlate are noted.