BACKGROUND: The activity of the renin-angiotensin-aldosterone system (RAAS) is directly related to overweight and sedentary lifestyles, both of which are associated with hypertension. Aerobic exercise helps control blood pressure (BP) by acting on mechanisms of blood pressure regulation, such as plasma renin activity (PRA). OBJECTIVE: To assess the effect of aerobic exercise on plasma renin activity in overweight hypertensive patients. METHODS: Blood pressure, serum biochemistry and anthropometric parameters of twenty subjects were measured before and after a 16-week exercise training program, three days a week, at 60-80% of maximal heart rate. Data were expressed as mean ± standard deviation or median and interquartile range and analyzed using the student's t-test, Mann-Whitney test, and ANOVA (p < 0.05). RESULTS: Mean age of the study population was 57 ± 7.0, and mean body mass index was 30 ± 3.5 kg/m². The aerobic training decreased body fat (35 ± 7.8 to 30 ± 5.6 %), heart rate (HR) (80 ± 10.4 to 77 ± 8.5 bpm), and pulse pressure (PP) (50 ± 11.8 to 46 ± 10.0 mmHg) (p < 0.05), but not plasma renin activity, which ranged from 0.8 (0.45-2.0) to 1.45 (0.8-2.15) ηg/ml/h (p = 0.055). The group that achieved a reduction in waist circumference (WC) (n = 8) experienced also a reduction in systolic BP and PP (p < 0.05). In the group without reduction in WC, none of the BP variables changed. Plasma renin activity (PRA) was not associated with any variable studied. Aerobic training was associated with a decrease in PP in the study group as a whole and with a decrease in systolic BP in the subgroup who experienced a decrease in waist circumference. CONCLUSION: The aerobic exercise training failed to reduce plasma renin activity in overweight hypertensive patients.
Exercise; renin; hypertension; overweight; obesity
