Static exercise in untreated systemic hypertension.

The circulatory responses to sustained handgrip at 30 per cent of a maximum voluntary contraction of the forearm muscles (MVC) were examined in untreated hypertensive patients. Arterial pressure increased in all patients, often attaining very high levels. Two main patterns of circulatory response were observed. In group i (8 patients) there was an increase in cardiac index and heart rate, with little or no change in systemic vascular resistance. These patients conformed to the pattern of response previously observed in normal subjects. Group 2 (6 patients) responded by an increase of systemic vascular resistance, a smaller rise in heart rate, and little or