Investigating the Effects of High-Intensity Interval Training on Baroreflex Sensitivity

Abstract

Cardiovagal baroreflex sensitivity (cvBRS) is known to be influenced by endurance exercise. In fact, endurance exercisers typically display a greater cvBRS compared to sedentary controls. Despite the merits of endurance training, adherence to exercise is a problem for many individuals. High-intensity interval training (HIIT) protocols generally involve less time and work completed while imparting similar cardiovascular responses compared to endurance training. To our current knowledge, the findings of HIIT and cvBRS have been equivocal. This study investigated the effects of 12-weeks of HIIT on cvBRS and the relationship between cvBRS and measures of arterial stiffness in 16 young, healthy males. Following HIIT, cvBRS appeared to be unchanged along with most measures of arterial stiffness (carotid to femoral pulse wave velocity, common carotid artery (CCA) distensibility, and compliance); however, CCA intima-media thickness (IMT) significantly improved. Systolic blood pressure, a major determinant of cvBRS, was unchanged, while resting heart rate appeared to improve following 12-weeks of HIIT. Therefore, these findings suggest that in this sample, 12-weeks of HIIT does not appear to influence cvBRS.