Influência de uma ingestão previa de suco de beterraba na ocorrência, magnitude e duração da hipotensão pós exercício

Abstract

The search for alternative treatments for the control and prevention of blood pressure is on the rise, exemplified by the consumption of beetroot juice as a potent vasodilator, which promotes a reduction in blood pressure hours after intake, in addition to the effects of physical exercise, where even a single session can reduce blood pressure, a phenomenon known as Post-Exercise Hypotension (PEH). Although hypertension treatment is effective in most cases, a portion of the population does not exhibit a hypotensive response to physical exercise or the consumption of nitrate-rich foods. In this context, the objective of this study is to investigate how the ingestion of beetroot juice before exercise influences the prevalence, magnitude, and duration of PEH in a sample of individuals with hypertension.This randomized, controlled, crossoverdesigned study included 28 hypertensive participants. The volunteers participated in three sessions: two experimental sessions involving the ingestion of 140 ml of beetroot juice rich in 800 mg nitrate or 140 ml of a nitrate-poor control beverage, combined with an aerobic exercise session via a treadmill test; and one control session without aerobic exercise and without beverage intake. Blood pressure was measured before, immediately after exercise, and every 10 minutes during the post-exercise recovery period. Ambulatory blood pressure was assessed using ambulatory blood pressure monitoring. Plasma nitrite, malondialdehyde, total antioxidant capacity, and biochemical analyses were performed. Statistical analysis of the data was conducted using a two-way repeated measures ANOVA test, via Jamovi version 1.6.1. A significant increase in plasma nitrite of 24.16% was observed after aerobic exercise compared to baseline values (p<0.014), with a further increase of 16.3% after exercise (p=0.048). This was not observed in the control beverage session. Systolic PEH was observed at 20 and 50 minutes, and diastolic PEH at 10, 30, and 50 minutes postexercise in the beetroot juice protocol. Similarly, a significant reduction in systolic blood pressure was observed at 20 and 50 minutes during the beetroot juice session compared to the control beverage session. Therefore, beetroot juice demonstrated a potential enhancing effect on PEH during the first hour post-exercise.