Abstract P161: Inspiratory Muscle Training and Aerobic Training in the Treatment of Hypertension: Baroreflex Sensitivity, Sympathetic Activity and Endothelial Function Responses

Arterial hypertension is associated to sympathetic hyperactivity and endothelial dysfunction. Aerobic training (AT) is highly recommended to improve vascular function minimizing complications and Inspiratory muscle training (IMT) has demonstrated beneficial effects in this population, especially improving cardiovascular autonomic control. We sought to observe the effects of both training modalities on baroreflex sensitivity, sympathetic activity and endothelial function, in patients with controlled arterial hypertension. 10 patients (55±4 years old, both genders) were included and allocated into two groups: IMT (n=5, 7days/week, 30min/day, load=30%PImax) and AT (n=5, 2days/week, 1hour/day, load=70%HRmax). Both training protocols were performed during 12 weeks. Blood pressure (BP) and heart rate (HR) signals were recorded before and after protocols, as well as the other evaluations, by pulse telemetry (Finometer®PRO) and ECG (PowerLab®). Arterial baroreflex sensitivity was analysed by sequence method. Sympathetic activity was evaluated by microneurography (PowerLab®) and the endothelial function was evaluated by flow mediated dilation (EnVisor CHD, Philips, Bothell, WA, USA). After 12 weeks treatment IMT improved baroreflex sensitvity to both tachycardic and bradycardic responses respectively (BRR Down Gain (mean): IMT=26.51(±1.7)vs15.57(±6.7), AT=13.94(±5.5)vs17.92(±1.6); BRR Up Gain (mean): IMT=17.16(±1.2)vs16.28(±1.1), AT=12.39(±5)vs12.69(±3.3)). Additionally, we observed reduction of sympathetic activity in both groups (IMT:33.23±11.79vs25.07±13.28; AT:29.88±7.07vs24.09±6.37) and improvement of endothelial function independent of the treatment (IMT:6.4±2.18vs7.22±2.08; AT:5.49±7.43vs7.06±3.12). Regarding the responses to inspiratory muscle training and aerobic training on autonomic cardiovascular control and endothelial function in Hypertension, we demonstrated for the first time that IMT and AT present quite similar effects in patients with controlled blood pressure.