| Summary: | It is still not known whether dietary nitrate can improve blood pressure (BP) and muscular strength in prehypertensives women. The current study investigated the effects of chronic (14-day) nitrate-rich beetroot extract supplementation on the blood pressure responses, maximal isometric handgrip strength and breath nitric oxide level in pre-hypertensive women. In a double-blind, randomized, crossover design, 9 prehypertensives females completed all assessments at pre-supplementation (as control; PRE) and 2-h after orally consumed beetroot extract (BRE; 250 mg·kg−1·day−1) and placebo (PLA; red coloring powder with negligible NO3− and NO2− content), with a washout period of 10 days separating each trial. BRE reduced systolic blood pressure (BRE: 126 ± 2.2 vs. PLA: 132 ± 4.0 vs. PRE: 131 ± 3.2 mmHg; P < 0.05). Similarly, diastolic blood pressure (BRE: 80 ± 4.6 vs. PLA: 84 ± 4.5 vs. PRE: 82 ± 4.4 mmHg; P < 0.05) and mean arterial pressure (BRE: 95 ± 3.5 vs. PLA: 100 ± 3.7 vs. PRE: 98 ± 3.4 mmHg; P < 0.05) were all lowered following BRE supplementation. However, no statistically significant changes were observed in maximal isometric handgrip strength across the trial condition. Additionally, resting fractional exhaled nitric oxide was elevated by ~124% and ~138% compared to the PRE and PLA condition, respectively (both P < 0.05). These findings suggest chronic (14-day) beetroot extract supplementation can significantly improve BP indices in the high-normal BP (prehypertension) population, but not handgrip strength. © 2020, Springer Nature Singapore Pte Ltd.
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