Effect of exercise training on plasma catecholamines and haemodynamics of adolescent hypertensives during rest, submaximal exercise and orthostatic stress

Abstract

Twelve adolescents with essential hypertension were studied to determine the effect of exercise training on plasma catecholamine concentrations, blood pressure and cardiovascular haemodynamics at rest and during submaximal exercise and orthostatic stress. Maximal oxygen consumption (VO2max) increased 13% with training while body weight and body fat did not change. Resting systolic and diastolic blood pressures decreased significantly with training, while plasma norepinephrine and epinephrine levels were unchanged. The increase in systolic blood pressure in response to standing was significantly lower after training, while the plasma catecholamine response was not significantly different. At the same absolute work rate after training, the subjects' systolic and diastolic blood pressures, heart rates, and plasma norepinephrine and epinephrine levels were significantly lower than before training. At the same relative work rate after training, the blood pressure response was the same as before training despite significantly higher plasma norepinephrine levels. Thus, the training-induced changes in resting blood pressures and blood pressure responses to orthostatic and submaximal exercise stress cannot be attributed to decreases in plasma catecholamine levels.