Fig. 2.
Effects of beetroot juice treatment on the rate-pressure product. Bars represent means ± SD of the heart rate × systolic blood pressure product, expressed in beats·min−1·mm Hg−1 × 10−4, for a placebo control orange juice treatment and an isocaloric, isovolumetric beetroot juice treatment on separate days in 12 normotensive, young adult, African-American, female university students. The treatments are compared at rest (baseline) and at constant workload power outputs corresponding to 3 submaximal levels of aerobic exercise (40%, 60%, and 80% of each subject’s predetermined peak oxygen consumption (V̇O2peak)). *, Difference between the control and beetroot juice treatments was statistically significant at p < 0.01.