The Effects of a Multi-Flavonoid Supplement on Cardiac Autonomic Regulation

Antioxidant supplementation has been shown to stimulate positive effects on cardiovascular health including a reduction in blood pressure by alleviating arterial stiffness, but little is known of the benefits of antioxidants on the autonomic nervous system. This study aims to look at the effects of a multi-flavanoid supplement combined with an acute bout of exercise and its effects on heart rate variability and autonomic function in pre-hypertensive, middle-aged individuals. 20 pre-hypertensive middle-aged individuals were randomly assigned to the placebo or treatment group. Subjects reported to the lab for baseline measurements. Beat-to-beat BP was measured on each subjects left arm and heart rate (HR) was monitored using a three lead electrocardiogram to attain cardiac autonomic modulation variables. Subjects were lying on a motorized tilt table, supine for 5 minutes, tilted head-up for 5 minutes and were lying supine again for 5 minutes, while measurements were being taken. Subjects supplemented for two weeks and returned for post measurements. The multi-flavonoid antioxidant supplementation showed favorable effects on the ANS by lowering the sympathetic outflow, and there was no additive effect of exercise and supplementation following the acute bout of aerobic exercise.