[Exercise capacity and cardiovascular responses to exercise in hemiplegic patients]

We studied how the severity of hemiparesis was related to cardiovascular and metabolic responses to exercise. Eleven clinically stable patients who had had strokes were studied two to four weeks after they began walking as rehabilitation. After motor function of the lower limbs was assessed, the patients were divided into two groups according to Brunnstrom stage: one group comprised patients at stages III, IV, and V of lower limb function (n = 5), and the other comprised patients at stage VI (n = 6). A control group of 6 patients who had been hospitalized because of benign paroxysmal postural vertigo was also studied. Exercise consisted of 3-minute walks at speeds of 1.6, 3.2, and 4.8 km/hr. Blood pressure, heart rate, and the concentrations of catecholamines and of lactic acid in blood were measured before and after each stage of exercise. The double product (systolic blood pressure x heart rate) was also calculated. Changes in these variables were compared among the three groups. Increases in walking speed were associated with increases in systolic blood pressure and heart rate in hemiparetic patients, but no such changes occurred in the control group. In the patients at Brunnstrom stages III, IV, and V, the double product and the lactic acid level increased, and after the patients walked at the highest speed these were significantly higher than in the other two groups. Serum catecholamine levels did not differ among the three groups during exercise. Low intensity exercise can increase cardiovascular responses, and anaerobic metabolism can become dominant in patients with poor motor function.