The influence of habitual breaks in sedentary time on cardiovagal baroreflex function
Myles W O'Brien1,1, Amera Al-Hinnawi1,1, Yanlin Wu1,1
1Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, Nova Scotia, Canada.
Abstract:
Sedentary time has recently been included in the 24-h activity guidelines. However, the impact of habitual sedentary patterns on autonomic cardiovascular regulation are unclear. We tested the hypothesis that more sedentary time and fewer sedentary breaks were associated with lower cardiovagal baroreflex sensitivity. More frequent sedentary breaks, but not total sedentary time, was independently and positively associated with vagally mediated blood pressure control. Breaking up sedentary time could be more important than total sedentary time for cardiovascular health. Novelty: Breaks in sedentary time is an independent predictor of cardiovagal baroreflex sensitivity, with more frequent breaks associated with better vagally mediated blood pressure regulation.
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