A single bout of moderate intensity resistance exercise improves neural mechanisms of arterial pressure control in L‐NAME hypertensive rats (884.14)

Abstract

Resistance training has been used as non‐pharmacological approach for control hypertension. A single bout of exercise can lead to a post exercise decreased blood pressure especially in hypertensive individuals. However neural central mechanisms involved in this modality of exercise remain unclear. Therefore the aim of this study was to evaluate the acute effects of a single bout of resistance exercise (RE) on blood pressure, baroreflex sensitivity (BRS) and cardiac autonomic balance in L‐NAME hypertensive rats. The resistance exercise (RE) consisted of 10 sets of 10 repetitions with 1 minute of interval between sets performed at 60% of one repetition maximum test, in squat‐training apparatus. Mean arterial pressure (MAP) was measured by a catheter placed in the carotid artery and recorded 15 before (baseline) and during 120 minutes post exercise. BRS was analyzed by sequence method and cardiac autonomic balance by heart rate variability in the frequency domain. Hypertension decreased BRS (from 2.03 ± 0.3 to 1.05 ± 0.2 mmHg/s, p<0.05) and increased both LF/HF ratio (from 0.12 ± 0.03 to 0.34 ± 0.05 nu, p<0.01) and LFsys (from 2.69 ± 0.1 to 5.19 ± 0.5 mmHg2, p<0.05) in baseline time. A single bout of moderate RE reduced MAP between 45’ to 120’ (p<0.001) and heart rate (HR) from 75’ to 120’ (p<0.05). Furthermore increased BRS from 15’ to 105’ (p<0.01) and both LF/HF ratio (p<0.05) and LFsys (p<0.001) were reduced. These results suggest that a single bout of moderate RE promotes a better hypertension control by improved BRS and cardiac autonomic balance in L‐NAME hypertensive rats.Grant Funding Source: Supported by FAPITEC/SE