Effects of Exercise Training on Blood Pressure and Renin-Angiotensin System Activation in Overweight Postmenopausal Women in the Dose-Response to Exercise in Women (DREW) Study

Abstract

Exercise training is thought to be an effective non-pharmacologic therapy for mild hypertension. A potential mediator in the antihypertensive effect of exercise training is the renin-angiotensin system. PURPOSE: To determine effects of different amounts of exercise training in overweight post-menopausal women on blood pressure (BP) reduction and renin-angiotensin system activation. METHODS: 450 sedentary, overweight or obese, mildly hypertensive, postmenopausal women, aged 45–75 yr were recruited and assigned to one of three exercise training groups expending 4, 8, or 12 kcal-kg-1 -wk-1 (KKW) for 6 months, or to a non-exercise control group. Maximal oxygen consumption (VO2max) and BP were among the primary outcome variables measured pre- and post-training. As part of an ancillary study, plasma renin activity (PRA) and plasma aldosterone were also measured pre- and post-training. Of the subjects who completed training, 118 had usable pre-and post-training plasma samples for PRA and/or aldosterone. Baseline and change (δ = post-training minus pre-training) variables were analyzed using a one-way ANOVA or Wilcoxon test. RESULTS: Baseline values of VO2max, systolic BP, and diastolic BP did not differ among groups; baseline concentrations of PRA and aldosterone also did not differ among groups. After training, δVO2max was significantly greater in the 8 (+1.43 ml/kg/min, +10.5%) and 12 (+2.16 ml/kg/min,+13.8%) KKW groups compared with controls (p=0.0001). However, there were no significant within- or among-group changes in systolic or diastolic BP or in hormone concentrations. Linear regression demonstrated that changes in BP were not significantly correlated with changes in either PRA or aldosterone. CONCLUSION: Under the conditions of this study, 6 months of exercise training at 8 and 12 KKW increased fitness in mildly hypertensive overweight postmenopausal women, but did not significantly reduce BP or alter PRA and aldosterone concentrations.