Research

Hormonal

A single dose of inorganic nitrate (12.9 mmol) improves exercise capacity in patients with heart failure with preserved ejection fraction (HFpEF) by increasing peak oxygen uptake and cardiac output, without improving exercise efficiency.

If you have heart failure with preserved ejection fraction, taking a specific dose of inorganic nitrate (found in beetroot juice) before exercise can help you breathe better and move more oxygen to your muscles during intense activity. However, it does not make your body more efficient at using that oxygen, and you must avoid antibacterial mouthwash to ensure the supplement works.

GoodSupportsHIGH confidence
NO3− supplementation significantly enhanced the reduction in systemic vascular resistance at peak exercise... This was accompanied by a significant increase in the cardiac output... Our data suggest that NO3− improves exercise capacity in HFpEF by improving the peripheral response to exercise and by providing greater O2 delivery to exercising muscles.
Payman Zamani et al. · Circulation · 2014

Why this rating

Randomized, double-blind, crossover study with 17 subjects, showing statistically significant improvements in secondary endpoints (peak VO2, cardiac output).

Source

Effect of Inorganic Nitrate on Exercise Capacity in Heart Failure With Preserved Ejection Fraction

Payman Zamani et al. · Circulation · 2014

DOI 10.1161/circulationaha.114.012957

crossover · n=17Cited 304×
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DOI resolved against Crossref · corpus check 2026-06-10

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