Cardiovascular response to isometric stress (IS) applied to the upper and the lower extremities, and general isometric stress amounting to 30% of the maximum productive force (MPF) were compared in 50 normal subjects and 60 coronary patients. Hemodynamic values were significantly higher at 30% MPF general isometric stress tolerance threshold, as compared to those seen in the last minute of the maintenance of IS of the same force by the upper extremities. Hemodynamic responses to IS, applied to the lower extremities, and to general 30% MPF isometric stress were basically similar. The general 30% MPF isometric stress was more sensitive with respect to the diagnosis of coronary disease, while the test's specificity and predictive value were fairly high. The sensitivity of the lower-extremity IS test was somewhat lower, as compared to that of the general isometric stress test, yet it is much higher, as compared to the upper-extremity IS test, and can therefore be used in screening programs.