We investigated the influence of angiotensin-converting enzyme inhibitor (ACEi) treatment and physical exercise on arterial pressure (AP) and heart rate variability (HRV) in volunteer patients with hypertension. A total of 54 sedentary volunteers were divided into three groups: normotensive (NT Group), hypertensive (HT Group) and HT volunteers treated with ACEi (ACEi Group). All volunteers underwent an aerobic physical-training protocol for 15 weeks. HRV was investigated using a spectral analysis of a time series of R-R interval (RRi) that was obtained in a supine position and during a tilt test. Physical training promoted a significant reduction in the mean arterial pressure of the HT group (113 ± 3 vs. 106 ± 1 mm Hg) and the ACEi group (104 ± 2 vs. Keywords: aerobic physical training; angiotensin; heart rate variability INTRODUCTION Hypertension is highly prevalent in the adult population and represents one of the leading causes of morbidity and mortality worldwide. 1,2 This condition is directly related to the development of cardiovascular diseases, encephalic vascular accident and renal insufficiency. 3 The risk factors for hypertension are associated with many other factors, including lifestyle. 4 The excessive ingestion of salt and alcohol, obesity, smoking and sedentariness represent the main behavioral factors that contribute to the occurrence and development of hypertension. 5 The treatment of hypertension consists mainly of a pharmacological approach, and the angiotensin-converting enzyme inhibitors (ACEis) are an important class of medications. 6 ACEis reduce arterial pressure (AP) by decreasing the peripheral vascular resistance, and they reduce cardiac hypertrophy and the proliferation of vascular smooth muscle cells. 7-9 Additionally, ACEis have an important role in cardiac autonomic control. Some studies have shown that ACEi treatment of hypertension in experimental animals and humans improves baroreflex

Ovariectomy did not change the tonic autonomic control of the heart and, in addition, reduced the participation of sympathetic component in cardiac modulation. Physical training, on the other hand, increased the participation of parasympathetic modulation on the HRV, including ovariectomized rats.

SummaryBackground: The nitric oxide (NO) synthesis blockade is characterized by an increase in the cardiac sympathetic activity and the physical training promotes the decrease in the sympathetic activity.