Does beet juice improve athletic performance?

A little, for some people and some kinds of effort. A 2020 meta-analysis of 80 crossover trials found dietary nitrate improved exercise performance against placebo by an effect size of 0.174 (95% CI 0.120 to 0.229), which is small. Most of those trials were in young, recreationally active men. In the 26 studies of well-trained endurance athletes the effect was 0.021, with an interval that runs from -0.103 to 0.144, and in the 6 women-only studies it was 0.116, with an interval that also crosses zero.

Established. In healthy, recreationally active adults, beetroot juice and other nitrate supplements give a small, measurable gain in lab tests of exercise. Every large meta-analysis on this page agrees on the direction. A 2022 analysis of 123 studies with 1705 people put the overall effect at 0.101 (95% CI 0.051 to 0.151) and found beetroot juice worked where nitrate salts did not.

Unsettled. Whether it helps in a race is not settled. A 2017 meta-analysis of 76 trials found longer time to exhaustion (effect size 0.33, 95% CI 0.15 to 0.50) and no significant gain in time trials, the format closest to competition. Trials in elite athletes are tiny, between 8 and 12 people each, and they mostly found nothing.

What the trials found

Time to exhaustion moves more than race time

Riding or running until you cannot continue is where nitrate does best. The 2017 meta-analysis put that effect at 0.33, and an umbrella review of 20 meta-analyses found the same size, 0.33 (95% CI 0.19 to 0.47), with larger gains at doses of at least 6 mmol (372 mg) a day taken for more than 3 days. Most of the reviews inside that umbrella were rated low or critically low quality. In the 28 time trials of the 2017 analysis, where people cover a set distance as fast as they can, the effect was -0.10 (95% CI -0.27 to 0.06) and not significant.

Juice, not salts

The 2022 analysis of 123 studies found beetroot juice effective and nitrate salts not (P = 0.629). A 2021 analysis of 56 nitrate-food studies found a trivial benefit across nitrate-rich foods (SMD 0.15), which held for beetroot and not for red spinach, Swiss chard or rhubarb. The same review found no effect in females.

Sprints and muscle

In 6 studies of 30-second cycling sprints, beetroot juice shortened the time it took to reach peak power (SMD -0.66, 95% CI -1.127 to -0.192) and did not raise mean, peak or minimum power. A 2026 meta-analysis of 23 trials in 401 healthy adults found the same pattern in four Wingate-based studies, and its authors rated the certainty low for most outcomes. A 2024 meta-analysis of 27 trials in healthy men found muscular endurance rose slightly in the 16 trials that measured it (SMD 0.31, 95% CI 0.10 to 0.51). For repeated sprints, a review of 18 studies found that only a third showed any gain, and suggested about 5 to 6 mmol of nitrate in 2.4 fl oz (70 ml) of juice, twice a day, for at least 3 to 6 days. A separate 2026 meta-analysis of 33 studies reported gains in repeated sprints (SMD 0.38, 95% CI 0.17 to 0.59), and its authors call the result hypothesis-generating.

Trained and elite athletes

Across 38 trials, beetroot juice raised VO2max slightly (SMD 0.24, 95% CI 0.11 to 0.37), and in highly trained athletes the effect was 0.07, with an interval crossing zero. Single trials in the very fit point the same way. Eight days of high-dose juice did not change 1500 m times in 8 elite runners, though two individual responders were identified. Five days of nitrate did not change 1000 m times in 9 international speed skaters. A concentrated dose did not change 200 m times in 12 elite swimmers under competition-like conditions. Twelve swimmers cannot detect the 1% differences that decide elite races, so that is not proof the effect is absent. One trial of 12 well-trained cyclists did find 10 km time trials about 1.6% faster after 7 days of 12.4 mmol a day, in a lab, against the null results above.

Expectation, caffeine, altitude

In 2026, 67 trained cyclists were given juice or placebo and told either one, in all four combinations. A single dose of about 552 mg nitrate did not change 20-minute virtual time-trial power, and neither did believing they had taken it. Adding caffeine to beetroot juice gave no significant extra gain (SMD 0.28, 95% CI -0.08 to 0.64) in a 2025 meta-analysis of small blinded trials. At high altitude, 9 trials in 161 people found nitrate raised blood nitrite and did not improve VO2max.

People with heart, lung or metabolic disease

In 22 crossover trials, nitrate did not change exercise time, peak oxygen uptake or 6-minute walk distance. Time to exhaustion moved by 0.11 (95% CI -0.12 to 0.34). The trials were small and underpowered.

Who should be careful

Not for everyone. Concentrated doses can upset the stomach in susceptible athletes, according to the IOC consensus, which gives no frequency and says to try nitrate thoroughly in training before using it in competition.

Antibacterial mouthwash blunts the effect. In 12 volunteers drinking 2.4 fl oz (70 mL) of juice twice a day for 6 days, rinsing with a strong mouthwash cut the rise in blood nitrite, and the 2022 meta-analysis found practices that reduce oral bacteria may weaken the performance effect. A review of beetroot juice risks notes that drinking it can push nitrate intake past the accepted daily limit, and that data on harms are far thinner than data on benefits, so a balanced risk assessment cannot yet be made. In 8 adults on dialysis, a single dose raised blood nitrate higher than in 7 healthy volunteers and did not change blood pressure or potassium. Anyone on dialysis takes this question to their nephrologist. We found no trial in adolescents or in pregnancy.

What expert bodies say

The 2018 IOC consensus statement on supplements lists nitrate with caffeine, creatine and specific buffering agents as one of the few supplements with good evidence of benefit. Its summary table links nitrate to 4% to 25% longer time to exhaustion and 1% to 3% better time trials lasting under 40 minutes. Those ranges come from selected studies, and the meta-analyses above find smaller and less consistent time-trial effects.

How we searched

What would change this answer

• Trials that measure real race results in competition. None of the trials we found did.
• Larger trials in women. They are a small minority of participants, and the women-only studies found no clear effect.
• Larger trials in elite athletes. Groups of 8 to 12 cannot detect the 1% differences that matter at that level. Registered trials include two completed studies of strength and grip that have not posted results.
• Longer trials. The athlete trials here loaded nitrate for 5 to 8 days.

More on the food itself: beet juice, and the evidence on beet juice and blood pressure.

Sources

1. ev-bjap-01 · Meta-analysis or systematic review · systematic review and random-effects meta-analysis of randomized crossover placebo-controlled trials · n = 80 studies
   Random-effects meta-analysis demonstrated that exercise performance improved with NO3 supplementation compared with placebo (d = 0.174; 95% confidence interval (CI), 0.120-0.229; P < 0.001).
   
   Who: Young healthy adults in randomized crossover placebo-controlled trials of nitrate
   Effect: overall d = 0.174 (95% CI 0.120 to 0.229); well-trained (VO2max at least 65 mL/kg/min, 26 studies) d = 0.021 (95% CI -0.103 to 0.144); women only (6 studies) d = 0.116 (95% CI -0.126 to 0.358)
   Certainty: Large evidence base, but the overall effect is small and the studies are mostly in young recreationally active men.
   Med Sci Sports Exerc, 2020 · checked 2026-10-07 · we read the abstract
2. ev-bjap-02 · Meta-analysis or systematic review · systematic review and random-effects meta-analysis with subgroup analyses by food, sex and fitness · n = 56 nitrate studies
   Trivial but significant benefits were demonstrated for consumption of nitrate and polyphenol-rich foods (SMD=0.15 and 0.17, respectively, p<0.001), including performance in time-trial, time-to-exhaustion and intermittent-type tests, and following both acute and multiple-day supplementation, but no effect of nitrate or polyphenol consumption was found in females.
   
   Who: Adults in endurance performance studies of nitrate-rich foods
   Effect: nitrate-rich foods SMD 0.15 (p < 0.001); benefit for beetroot, none for red spinach, Swiss chard and rhubarb; no effect in females or in well-trained males (VO2max at least 65 mL/kg/min)
   Certainty: Pools crossover trials of mixed quality; 'trivial' is the authors' own label for the effect size.
   J Int Soc Sports Nutr, 2021 · checked 2026-10-07 · we read the abstract
3. ev-bjap-03 · Meta-analysis or systematic review · systematic review and fixed-effects meta-analysis with meta-regression · n = 76 trials
   TTE trials had a small to moderate statistically significant effect in favour of dietary NO3- supplementation (ES = 0.33, 95 % Cl = 0.15-0.50, p < 0.01).
   
   Who: Adults in placebo-controlled trials of nitrate with exercise lasting at least 30 seconds
   Effect: time to exhaustion ES 0.33 (95% CI 0.15 to 0.50); time trial (28 trials) ES -0.10 (95% CI -0.27 to 0.06), not significant; graded exercise ES 0.25 (95% CI -0.06 to 0.56)
   Certainty: Search to October 2015; later meta-analyses confirm the time-to-exhaustion benefit and the weaker time-trial signal.
   Sports Med, 2017 · checked 2026-10-07 · we read the abstract
4. ev-bjap-04 · Meta-analysis or systematic review · systematic review and meta-analysis with meta-regression and subgroup analysis · n = 1705
   Ingestion of 5-14.9 mmol⋅d-1 taken ≥150 min prior to exercise appears optimal for performance gains and athletes should be aware that practices controlling oral microbiota diversity may decrease the effect of nitrate.
   
   Who: Healthy adults in randomized controlled trials of nitrate salts, beetroot juice or high-nitrate diets
   Effect: overall SMD 0.101 (95% CI 0.051 to 0.151, I2 = 0%); beetroot juice effective (P < 0.001), nitrate salts not (P = 0.629); practices harmful to oral bacteria reduced the effect
   Certainty: The overall effect is small; dose and timing come from subgroup and meta-regression analyses, which are observational within the review.
   Adv Nutr, 2022 · checked 2026-10-07 · we read the abstract
5. ev-bjap-05 · Meta-analysis or systematic review · systematic review and random-effects meta-analysis of randomized controlled trials · n = 27 studies
   BRS administration resulted in a positive effect on muscular endurance (SMD: 0.31; 95% confidence interval (CI): 0.10 to 0.51; p < 0.01; n = 16 studies).
   
   Who: Healthy male individuals in randomized controlled trials of beetroot-based supplements
   Effect: muscular endurance SMD 0.31 (95% CI 0.10 to 0.51, 16 studies); strength SMD 0.26 (95% CI 0.03 to 0.48, 18 studies); strength in a fatigued state SMD 0.64 (95% CI 0.25 to 1.03)
   Certainty: Men only; acute and short-term protocols; no data on long-term strength training adaptations.
   J Am Nutr Assoc, 2024 · checked 2026-10-07 · we read the abstract
6. ev-bjap-06 · Meta-analysis or systematic review · systematic review and random-effects meta-analysis · n = 6 studies
   A random effects model was performed on six studies and showed that dietary nitrate had significant effects on time-to-peak power (SMD: -0.66, 95% CI: -1.127 to -0.192, p = 0.006) but not on mean power, peak power, or minimum power.
   
   Who: Healthy recreationally active men and women doing 30-second cycling sprints
   Effect: time to peak power SMD -0.66 (95% CI -1.127 to -0.192); no significant effect on mean, peak or minimum power
   Certainty: Only six studies; too few women to test sex differences; the authors ask for caution.
   Nutrients, 2024 · checked 2026-10-07 · we read the abstract
7. ev-bjap-07 · Meta-analysis or systematic review · systematic review and random-effects meta-analysis of randomized controlled crossover studies · n = 5 studies per comparison
   In addition, no significant differences were found between the isolated supplements and the co-ingestion (CAF-SB/CAF: SMD = 0.12, 95% CI [-0.30, 0.54], p = 0.57; CAF-SB/SB: SMD = 0.12, 95% CI [-0.29, 0.54], p = 0.56; CAF-BJ/CAF: SMD = 0.06, 95% CI [-0.30, 0.41], p = 0.76; CAF-BJ/BJ: SMD = 0.28, 95% CI [-0.08, 0.64], p = 0.13).
   
   Who: Adults in blinded randomized crossover trials of supplements in endurance exercise over 35 seconds
   Effect: caffeine plus beetroot juice vs beetroot juice SMD 0.28 (95% CI -0.08 to 0.64), not significant
   Certainty: Few small studies with some risk-of-bias concerns; wide intervals.
   J Int Soc Sports Nutr, 2025 · checked 2026-10-07 · we read the abstract
8. ev-bjap-08 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized placebo-controlled crossover trials · n = 22 studies
   NO3- supplementation had no effect on aerobic performance with respect to maximal (SMD = 0.11, 95% CI: -0.12 to 0.34, p = 0.34) and submaximal (SMD = 0.16, 95% CI: -0.13 to 0.46, p = 0.27) TTE, VO2peak (SMD = 0.002, 95% CI: -0.37 to 0.38, p = 0.99), or 6MW (SMD = 0.01, 95% CI: -0.29 to 0.28, p = 0.96).
   
   Who: Individuals with cardiopulmonary and metabolic diseases in randomized placebo-controlled crossover trials
   Effect: maximal time to exhaustion SMD 0.11 (95% CI -0.12 to 0.34); VO2peak SMD 0.002 (95% CI -0.37 to 0.38); 6-minute walk SMD 0.01 (95% CI -0.29 to 0.28)
   Certainty: Small, heterogeneous trials with low statistical power; 46% of single trials reported benefit.
   Nutrients, 2024 · checked 2026-10-07 · we read the abstract
9. ev-bjap-09 · Meta-analysis or systematic review · systematic review and meta-analysis with meta-regression · n = 33 studies
   BJ supplementation significantly improved HIS (SMD = 0.38, 95% CI 0.17 to 0.59, p < 0.001), MPO (SMD = 0.43, 95% CI 0.21 to 0.64, p < 0.001), and VO₂max (SMD = 0.30, 95% CI 0.05 to 0.55, p < 0.001).
   
   Who: Participants in beetroot juice supplementation studies measuring VO2max, sprint and power
   Effect: high-intensity interval sprint SMD 0.38 (95% CI 0.17 to 0.59); mean power output SMD 0.43 (95% CI 0.21 to 0.64); VO2max SMD 0.30 (95% CI 0.05 to 0.55); heterogeneity low
   Certainty: Searched Google Scholar manually and pooled by brand and timing without significant subgroup differences; the authors' recommendation is stronger than their own caveat.
   Front Nutr, 2026 · checked 2026-10-07 · we read the abstract
10. ev-bjap-10 · Randomized controlled trial(s) · randomized double-blind crossover trial with nitrate-free beetroot placebo, 8 days · n = 8
    Acute and chronic BR supplementation did not reduce running V˙O2 or improve 1500-m TT performance of a group of elite distance runners, but two responders to BR were identified.
    
    Who: Eight male 1500-m runners (VO2peak 80 mL/kg/min, personal best 3:56)
    Effect: 1500 m time trial: placebo 4:10.4 vs beetroot 4:10.7 (acute), 4:11.4 vs 4:10.5 (chronic), no difference; two individual responders
    Certainty: Eight runners cannot rule out a 1% effect; shows the ceiling in elite athletes.
    Med Sci Sports Exerc, 2014 · checked 2026-10-07 · we read the abstract
11. ev-bjap-11 · Randomized controlled trial(s) · randomized double-blind placebo-controlled crossover trial, 5 days · n = 9
    Five days of high-dose nitrate supplementation did not change physiological responses and failed to improve single and repeated time-trial performances in world-class short-track speed skaters.
    
    Who: 9 international-level short-track speed skaters
    Effect: first 1000 m time trial 90.92 s (low dose) vs 90.95 s (high dose), ES 0.01; second 91.16 vs 91.55 s, ES 0.09
    Certainty: Juice blend rather than pure beetroot; very small sample of world-class athletes.
    Int J Sports Physiol Perform, 2018 · checked 2026-10-07 · we read the abstract
12. ev-bjap-12 · Randomized controlled trial(s) · randomized double-blind counterbalanced crossover trial, 7 days · n = 12
    Our results provide new evidence that chronic high-dose NO3- supplementation improves cycling performance of well-trained cyclists in both normoxia and hypoxia.
    
    Who: 12 well-trained cyclists
    Effect: 10 km time trial about 1.6% better with beetroot juice (p < 0.05); no difference between normoxia and hypoxia
    Certainty: Laboratory ergometer, single small trial; contrasts with null trials in elite runners and skaters.
    Nitric Oxide, 2019 · checked 2026-10-07 · we read the abstract
13. ev-bjap-13 · Randomized controlled trial(s) · randomized between-participant balanced placebo design, acute dose · n = 67
    In short, physiological and placebo effects of an acute dose of beetroot juice did not change 20-min time-trial performance during a virtual cycling platform.
    
    Who: 67 trained cyclists on a virtual cycling platform
    Effect: change in power output from baseline: told and given beetroot +2.06 W, told beetroot given placebo +4.29 W, told placebo given beetroot -0.12 W, told and given placebo +3.06 W; no significant effects
    Certainty: Acute single dose; real-world style setting; tests both the drug and the expectation effect.
    Res Q Exerc Sport, 2026 · checked 2026-10-07 · we read the abstract
14. ev-bjap-14 · Position of an expert body · consensus statement · n = —
    Supplements claiming to directly or indirectly enhance performance are typically the largest group of products marketed to athletes, but only a few (including caffeine, creatine, specific buffering agents and nitrate) have good evidence of benefits.
    
    Who: Elite athletes
    Effect: nitrate listed with caffeine, creatine and specific buffering agents as supplements with good evidence of benefits
    Certainty: Expert consensus without its own pooled analysis.
    Br J Sports Med, 2018 · checked 2026-10-07 · we read the abstract
15. ev-bjap-15 · Position of an expert body · consensus statement, summary table · n = —
    Supplementation has been associated with improvements of 4%–25% in exercise time to exhaustion and of 1%–3% in sport-specific TT performances lasting <40 min in duration.
    
    Who: Athletes in sport-specific time trials under 40 minutes
    Effect: time to exhaustion +4% to 25%; time trials under 40 min +1% to 3%; equivocal for tasks under 12 min
    Certainty: Summary of ranges from selected studies, not a pooled estimate; the meta-analyses above find smaller and less consistent time-trial effects.
    Br J Sports Med, 2018 · checked 2026-10-07 · we read the fulltext
16. ev-bjap-16 · Position of an expert body · consensus statement, summary table · n = —
    There may exist the potential for GI upset in susceptible athletes, and should therefore be thoroughly trialled in training.
    
    Who: Athletes using nitrate supplements
    Effect: possible gastrointestinal upset in susceptible athletes; trial in training first
    Certainty: No frequency is given for gut upset. Red urine (beeturia) and the nitrate ADI are covered in the beet juice and heart health cards.
    Br J Sports Med, 2018 · checked 2026-10-07 · we read the fulltext
17. bjc-dr-04 · Observational data · systematic review of studies of nitrate from beetroot juice and fatigue resistance during repeated sprints, 18 of 209 screened articles met inclusion criteria · n = 18 studies
    It seems that a chronic intake of ∼5-6 mmol of NO3- in 70 ml of BRJ, twice a day, for a minimum of 3-6 days could lead to a fatigue resistance improvement during repeated sprints.
    
    Who: 18 studies in people performing repeated sprint exercise
    Effect: in a third of the studies beetroot juice raised plasma nitrite and with it peak power, mean power, sprint repetitions, total work and time to task failure, while lowering fatigue index and sprint times; chronic protocols used about 5 to 6 mmol nitrate in 2.4 fl oz (70 mL) twice a day for at least 3 to 6 days, acute protocols 8.5 to 17 fl oz (250 to 500 mL) taken 2.5 to 3 hours before effort; improvements in fatigue resistance ranged from 1.2% to 5.38%
    Certainty: only a third of the studies found anything, which the review states plainly, and it did not pool them. The authors end by saying the practical meaning in the field should be explored, which is a polite way of saying a 1.2% change may not decide a race. These are concentrated sports products, not the juice sold in a supermarket
    Crit Rev Food Sci Nutr, 2021 · checked 2026-09-22 · we read the abstract
18. bjc-dr-05 · Randomized controlled trial(s) · randomized double-blind counterbalanced trial, 4.7 fl oz (140 mL) of concentrated beetroot juice or a sensory-matched nitrate-depleted placebo 2 hours before two maximal 200 m front-crawl time trials separated by 60 minutes of passive recovery, with blood sampling and perceived exertion recorded · n = 12
    In conclusion, acute BRJ supplementation did not enhance 200-m front-crawl performance, lactate responses, or perceived exertion in elite swimmers under competition-like conditions.
    
    Who: 12 elite male swimmers, mean age 20, 200 m personal best 115.7 seconds
    Effect: no difference in first time trial (116.7 against 117.2 s, p = 0.19), second time trial (117.8 against 117.8 s, p = 0.98) or the change between them (p = 0.40); blood lactate and perceived exertion also unchanged
    Certainty: 12 swimmers cannot detect the 1% differences that matter at elite level, so this is not proof of absence. It is still the most relevant design for the claim being sold, because it used a competition-like protocol and a proper nitrate-depleted placebo rather than water or a different drink
    Int J Sport Nutr Exerc Metab, 2026 · checked 2026-09-22 · we read the abstract
19. bjc-dr-06 · Observational data · systematic review of the benefits and risks of beetroot juice consumption · n = —
    Compared to studies on the beneficial effects, the amount of data and literature on the negative effects of BRJ is rather limited, and should be increased in order to perform a balanced risk assessment.
    
    Who: published literature on beetroot juice, nitrate and nitric oxide
    Effect: beetroot juice can readily raise nitrate intake above the acceptable daily intake, which stimulates endogenous formation of N-nitroso compounds, a class known to be carcinogenic and linked to other adverse effects; the authors record that literature on the negative effects is limited compared with that on benefits
    Certainty: this is a review rather than a measurement, and it names no threshold in milliliters. Endogenous N-nitroso formation from dietary nitrate is a mechanism, and the epidemiology of vegetable nitrate has repeatedly failed to show the harm the mechanism predicts. The useful part is the admission that a balanced risk assessment cannot currently be made
    Crit Rev Food Sci Nutr, 2021 · checked 2026-09-22 · we read the abstract
20. bjc-dr-08 · Randomized controlled trial(s) · single-center randomized single-blind placebo-controlled crossover study, one dose of 2.4 fl oz (70 mL) concentrated beetroot juice with 400 mg nitrate against a nitrate-free placebo juice in random order, separated by a 7-day washout, with blood sampled up to 44 hours after intake · n = 15
    The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels.
    
    Who: 8 adults on chronic hemodialysis and 7 age-matched healthy volunteers
    Effect: active juice raised plasma nitrate and nitrite in both groups; area under the curve and peak concentration of nitrate, though not nitrite, were significantly higher in dialysis patients than in healthy volunteers; blood pressure and plasma potassium were unaffected in both groups and no adverse events occurred
    Certainty: fifteen people in a kinetics study, designed to inform later efficacy trials rather than to show benefit. The higher nitrate exposure in dialysis patients is the point that matters clinically: the same dose lands harder when the kidneys are not clearing it. Potassium not moving after a single dose says nothing about repeated use, and anyone on dialysis takes this question to their nephrologist
    Nutrients, 2022 · checked 2026-09-22 · we read the abstract
21. nitr3-04 · Meta-analysis or systematic review · umbrella review with meta-analysis of RCT-based reviews · n = —
    It improved time-to-exhaustion tasks [standardized mean difference (SMD): 0.33; 95% confidence interval (CI) 0.19-0.47] with subgroup analyses indicating more pronounced improvements when a minimum dose of 6 mmoL/day (372 mg/day) and chronic (> 3 days) supplementation protocol was implemented.
    
    Who: 20 systematic reviews with meta-analyses
    Effect: time-to-exhaustion SMD 0.33 (95% CI 0.19-0.47)
    Certainty: AMSTAR-2 of most reviews is low or critically low
    Sports Med, 2025 · checked 2026-10-02 · we read the abstract
22. nitr3-05 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized trials · n = —
    BRJ produced a small statistically significant improvement in VO₂max/VO₂peak compared with placebo (SMD = 0.24, 95% CI [0.11, 0.37], p < 0.001; I2 = 48.3%). Effects were larger in recreationally active participants (SMD = 0.38) and were not clearly demonstrated in highly trained athletes (SMD = 0.07, 95% CI [-0.09, 0.23]).
    
    Who: adults in placebo-controlled trials
    Effect: SMD 0.24 (95% CI 0.11-0.37); trained athletes SMD 0.07 (-0.09 to 0.23)
    Certainty: after trim-and-fill SMD 0.19; moderate certainty
    Front Nutr, 2026 · checked 2026-10-02 · we read the abstract
23. nitr3-06 · Meta-analysis or systematic review · meta-analysis of RCTs · n = 161
    A total of 9 studies with a sample size of 161 cases were included in the analysis. The meta-analysis indicated that dietary nitrate supplement significantly elevated NO2- concentration (95% CI: 1.38 to 3.12; SMD = 2.25, P < 0.00001; I2 = 70%). However, there was no significant effect observed on VO2max (95% CI: -0.58 to 0.23; SMD = -0.17, P = 0.76; I2 = 0%)
    
    Who: 161 people at high altitude, 9 RCTs
    Effect: nitrite SMD 2.25 (1.38-3.12); VO2max SMD -0.17 (-0.58 to 0.23)
    Certainty: small total sample
    PLoS One, 2025 · checked 2026-10-02 · we read the abstract
24. nitr3-07 · Observational data · crossover trial (randomization not shown in quote) · n = 12
    12 healthy volunteers mouth-rinsed with STRONG, non-chlorhexidine mouthwash (WEAK) and deionised water (CON) 3 times a day, and ingested 70 mL BR (6.2 mmol NO3-), twice a day, for 6 days. ... the rise in plasma [NO2-] at 2 h was lower in STRONG compared with WEAK (by 89±112 nM) and CON (by 200±174 nM) and in WEAK compared with CON (all P<0.05).
    
    Who: 12 healthy volunteers, 2.4 fl oz (70 mL) beetroot juice (6.2 mmol nitrate) twice a day, 6 days
    Effect: plasma nitrite rise at 2 h lower with strong mouthwash by 200 +/- 174 nM vs water
    Certainty: small sample; resting blood pressure did not change
    Int J Sports Med, 2015 · checked 2026-10-02 · we read the abstract
25. bjvj-daily-r5-01 · Meta-analysis or systematic review · meta-analysis of RCTs · n = 401
    Twenty-three randomized trials involving 401 participants were included, and 21 contributed to the meta-analysis. BRJ improved time to peak power in four Wingate-based studies (SMD = -0.92, 95% CI: -1.29 to -0.54, p < 0.001) and handgrip strength (SMD = 0.40, 95% CI: 0.05 to 0.74, p = 0.027).
    
    Who: healthy adults aged 18 to 40 in 23 randomized trials published between 2014 and June 2026, 21 trials pooled
    Effect: time to peak power SMD -0.92 (95% CI -1.29 to -0.54), handgrip strength SMD 0.40 (95% CI 0.05 to 0.74), no effect on countermovement jump, peak or mean power, 10 m or 20 m sprint, perceived exertion, heart rate or blood lactate
    Certainty: GRADE low for most outcomes and very low for 20 m and lactate; few data in women. The positive finding rests on four Wingate studies.
    Nutrients, 2026 · checked 2026-09-25 · we read the abstract