The Effect of Acute Beetroot Juice Supplementation on Blood Pressure During High Intensity Interval Exercise

Abstract

Introduction: Hypertension is a major cardiovascular disease (CVD) risk factor. Low aerobic fitness is a contributing factor to the prevalence of hypertension. Previous research has shown that high intensity interval exercise (HIE) training causes more rapid and greater physiological adaptations compared to traditional aerobic training, therefore this would be the best protocol for the prevention and treatment of hypertension and CVD. Individuals’ blood pressure (BP) responses to exercise have been shown to provide predictive information for multiple heath risks. Beetroot juice has been found to reduce resting BP; however, the effects on BP responses to exercise are unknown. This study examined the BP responses during a HIE protocol. Methods: Ten normotensive participants were recruited (20 ± 1yr, 81.1 ± 11.4kg, 175 ± 8cm). On two separate occasions participants came into the laboratory and BP was measured at rest for 30 minutes, 2.5 hours following either beetroot juice or blackcurrant cordial ingestion. Then a exercise HIE protocol involving 10x60 seconds at 50% PPO and 10x60 seconds at 90% PPO was performed, HR and BP were measured throughout. Results: Trends were seen in reduced SBP at rest and reduced DBP and MAP responses throughout exercise when comparing beetroot juice supplementation to the blackcurrant placebo, however no significant differences were found (P> 0.05). Conclusions: Although findings showed no significant differences, the trends in reductions in SBP at rest and DBP response during exercise may possess clinical significance for both normotensive and hypertensive, active and inactive individual.