Dietary Nitrate Supplementation and Exercise Performance: An Umbrella Review of 20 Published Systematic Reviews with Meta-analyses.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of systematic reviews of randomized controlled trials
PubMed 40085422 · doi:10.1007/s40279-025-02194-6
What was done
An umbrella review following guidelines searched seven databases through July 2024 for systematic reviews with meta-analyses evaluating dietary nitrate supplementation versus placebo across 11 domains of exercise performance. Two reviewers independently extracted data, performed meta-analyses, and assessed review quality using AMSTAR-2.
What was found
Twenty systematic reviews with meta-analyses covering 180 primary studies and 2,672 participants were included. Nitrate supplementation produced statistically significant improvements in time-to-exhaustion tasks (SMD: 0.33; 95% CI: 0.19 to 0.47; larger with >= 6 mmol/day or 372 mg/day for > 3 days), total distance covered (SMD: 0.42; 95% CI: 0.09 to 0.76), muscular endurance (SMD: 0.48; 95% CI: 0.23 to 0.74), peak power output (SMD: 0.25; 95% CI: 0.10 to 0.39), and time to peak power output (SMD: -0.76; 95% CI: -1.18 to -0.33). The other performance outcomes showed no significant improvements (all p > 0.05). AMSTAR-2 quality ratings for most included reviews were low to critically low.
Why it matters
This umbrella review clarifies that nitrate ergogenic benefits are selective to specific endurance, muscular endurance, and power domains, with optimal effects requiring chronic dosing of at least 6 mmol per day.
Limits
The methodological quality of most included reviews was rated as low to critically low on AMSTAR-2. Specific performance outcomes that failed to reach significance, baseline participant fitness levels, and adverse effects were not reported in the abstract.
Cited by
- supports Dietary nitrates from plants convert to nitric oxide, which causes vasodilation and improves endurance exercise performance.