The acute impact of dietary nitrate supplementation on the postexercise hypotension response to high intensity interval exercise.

Abstract

Aim: High intensity interval training has emerged as a popular method to achieve chronic reductions in resting blood pressure, while the magnitude post exercise hypotension has been shown to be highly correlated with chronic reductions in resting blood pressure. Additionally, acute and chronic beetroot juice supplementation lowers blood pressure at rest and aids perfusion during exercise. However, there is little research on the hypotensive response to high intensity interval exercise and beetroot supplementation. Therefore primary aim of this study was to investigate the effect of acute BR supplementation on the PEH response to HIE. Methods: 5 male and 5 female non-hypertensive participants (age 19.9 ± 0.88 years) were recruited from a university population. Participants completed two identical high intensity interval exercise protocols on separate days, following supplementation of either concentrated beetroot juice or a placebo supplement 2.5 hours before exercise. Hemodynamic variables were measured for 30 minutes before exercise and then one hour after exercise cessation. Results: Two-way analysis of variance identified that SBP, DBP, and MAP all significantly dropped below their baseline values following high intensity interval exercise (P<0.05). Additionally, SBP and PP were significantly lower after exercise following beetroot juice supplementation compared to the placebo supplement (P<0.05). Gender sub-analysis showed the peak reduction in systolic blood pressure was greater with beetroot supplementation Conclusion: HIE produced a significant PEH response indicative of significant chronic training adaptations that could reduce CVD incidence. Furthermore, acute BR supplementation before HIE increased this response in males.