Comparison of cardiovascular risk in maximal isometric and dynamic exercise.

With the hypothesis that isometric exercise testing offers important clinical information yet is neglected because of overemphasis on its risk, we compared it with dynamic testing for variables indicative of myocardial ischemia. In a medical office, 287 patients were each subjected once to both a one-minute maximal handgrip stress test and maximal treadmill test while monitored noninvasively for cardiovascular responses. Systolic blood pressures usually increased more with the treadmill test, diastolic more with the handgrip. The treadmill tests caused greater mean heart rate and rate-pressure products, as well as more ST segment displacements, arrhythmias, and symptoms and signs. However, there were some unpredictable individual differences in the isometric blood pressure responses. Isometric testing is easy and useful and, if properly monitored, causes less risk to the patient than dynamic testing.