비트루트 주스 (질산)

This systematic review and meta-analysis investigated the chronic effects of sodium nitrate (NO₃⁻) supplementation on systolic blood pressure (SBP), diastolic blood pressure (DBP), and resting heart rate (RHR) in adults. Placebo-controlled randomized clinical trials (RCTs) involving participants aged ≥18 years and lasting at least one week were included. Studies with beetroot juice as an intervention and studies with animals were excluded. Searches in PubMed, Cochrane, LILACS, Web of Science, SCOPUS, and grey literature were conducted in June 2025. Effect estimates were pooled as mean differences (MD) with 95% CIs using a random-effects model with Hartung-Knapp adjustment and the inverse variance method. All analyses were performed using RStudio with the meta package. Risk of bias assessment was conducted using the PEDro scale. Six studies (n = 181 participants; 59% male; > 50 years of age) were eligible for analysis. Compared to the placebo condition, NO₃⁻ supplementation did not result in significant reductions in DBP (MD: -2.00 mm Hg; 95% CI: -4.37 to 0.38 mm Hg); SBP (MD: -3.81 mm Hg; 95% CI: -10.05 to 2.43 mm Hg); and RHR (MD: 0.34 bpm; 95% CI: -5.68 to 6.36 bpm). The average PEDro score indicated a low risk of bias (8.16 points). In conclusion, the current evidence does not support reductions in blood pressure levels in older adults following NO₃⁻ supplementation. Nevertheless, due to the limited number of available randomized controlled trials, further research is necessary to confirm these findings and to better understand the long-term effects of this compound on blood pressure.

BACKGROUND: The evidence about the synergy of combining caffeine (CAF) and nitrates on exercise performance has not been summarized, although there is a possibility of additive/synergistic effects of the co-ingestion of these substances given their different mechanisms of action in central (CAF) and peripheral tissues (nitrates). OBJECTIVES: The aim was to analyze the effects of co-supplementation of CAF and nitrates on sports performance in comparison to the isolated ingestion of these substances. METHODS: The databases of PubMed, Web of Science, Medline, CiNAHL and SPORTDiscus were used until June 2024 following PRISMA guidelines. Randomized controlled trials, at least one single-blind trial, conducted in adults were considered. A meta-analysis was performed using the random effects model to calculate the standardized mean difference estimated by Hedges' g and 95% confidence intervals (CIs) for studies with four arms. RESULTS: Six studies were included (N = 95). The meta-analysis revealed that caffeine and nitrates supplementation (CAF+nitrates) did not enhance performance in time trials (TTs) over the CAF alone (g = -0.06; 95% CI = -0.46 to 0.35; p = 0.78) or nitrates alone (g = 0.29; 95% CI = -0.12 to 0.70; p = 0.17). CAF+nitrates did not affect heart rate during submaximal exercise trials over CAF alone (g = 0.04; 95% CI = -0.31 to 0.40; p = 0.80) or nitrates alone (g = -0.15; 95% CI = -0.50 to 0.20; p = 0.40). Likewise, CAF+nitrates did not affect oxygen uptake during submaximal exercise trials over CAF alone (g = -0.04; 95% CI = -0.45 to 0.37; p = 0.84) or nitrates alone (g = -0.29; 95% CI = -0.70 to 0.12; p = 0.16). CONCLUSIONS: CAF+nitrates did not offer further benefits on exercise performance or physiological variables from the isolated intake of CAF and nitrates.

This systematic review and meta-analysis investigated the influence of dietary nitrate supplementation on performance metrics during cycling sprint exercise according to the PRISMA guidelines. Searches were conducted on MEDLINE, PubMed, ScienceDirect, Scopus, and SPORTDiscus databases up to September 2023. Inclusion criteria were healthy recreationally active men and women who consumed nitrate-rich and nitrate-deficient beetroot juice to assess performance outcomes of mean power, peak power, time-to-peak power, and minimum power during 30-s cycling sprints. Risk of bias was assessed using the Cochrane Risk of Bias 2 and TESTEX tools and funnel plots. 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. Subgroup analysis revealed that an acute low nitrate dose improved time-to-peak power (SMD: -0.977, 95% CI: -1.524 to -0.430, p < 0.001) but not after a multiday moderate nitrate dose (SMD: -0.177, 95% CI: -0.619 to -0.264, p = 0.431). These data suggest that acute nitrate supplementation can benefit time-to-peak power during 30-s cycling sprints, but due to the limited availability of data and heterogeneity in methodology, these results should be interpreted with caution. There was insufficient data on women to analyze sex-based differences. Future studies are required to provide insight on how supplementation regimen and population impact the effects of dietary nitrate for enhancing cycling sprint performance.

This systematic review and meta-analysis aimed to investigate the effects of beetroot (BR) or nitrate supplements on body composition indices. A systematic search was conducted for randomised controlled trials (RCT) published up to August 2022 among online databases including Scopus, PubMed/Medline, Web of Science and Embase. Meta-analyses were carried out using a random-effects model. The I2 index was used to assess the heterogeneity of RCT. A total of twelve RCT met the inclusion criteria for this meta-analysis. The pooled effect size of included studies indicated that BR or nitrate supplementation did not change body weight (weighted mean differences (WMD): -0·14 kg, 95 % CI -1·22, 1·51; P = 0·836; I2 = 0 %), BMI (WMD: -0·07 kg/m2, 95 % CI -0·19,0·03; P = 0·174, I2 = 0 %), fat mass (WMD: -0·26 kg, 95 % CI -1·51, 0·98; P = 0·677, I2 = 0 %), waist circumference (WMD: -0·28 cm, 95 % CI -2·30, 1·74; P = 0·786, I2 = 0 %), body fat percentage (WMD: 0·18 %, 95 % CI -0·62, 0·99; P = 0·651, I2 = 0 %), fat-free mass (WMD: 0·31 kg, 95 % CI -0·31, 1·94; P = 0·703, I2 = 0 %) and waist-to-hip ratio (WMD: 0, 95 % CI -0·01, 0·02; P = 0·676, I2 = 0 %). Subgroup analyses based on trial duration, BR or nitrate dose, study design, baseline BMI and athletic status (athlete v. non-athlete) demonstrated similar results. Certainty of evidence across outcomes ranged from low to moderate. This meta-analysis study suggests that BR or nitrate supplements cannot efficiently ameliorate body composition indices regardless of supplement dosage, trial duration and athletic status.

The clinical symptoms of chronic obstructive pulmonary disease (COPD) disease are accompanied by severely debilitating extra-pulmonary manifestations, including vascular dysfunction and hypertension. This systematic review evaluated the current evidence for several therapeutic interventions, targeting the nitric oxide (NO) pathway on hemodynamics and, secondarily, exercise capacity in patients with COPD. A comprehensive search on COPD and NO donors was performed on online databases. Of 934 initially found manuscripts, 27 were included in the review, and 16 in the meta-analysis. The analysis indicated inconsistent effects of dietary nitrate supplementation on exercise tolerance in COPD patients. Dietary nitrate supplementation decreased systolic (-3.7 ± 4.3 mmHg; p = 0.10) and diastolic blood pressure (BP; -2.6 ± 3.2 mmHg; p = 0.05) compared with placebo. When restricted to acute studies, a clinically relevant BP lowering effect of nitrate supplementation during diastole was observed (-4.7 ± 3.2 mmHg; n = 5; p = 0.05). In contrast, inhaled NO (iNO) at doses <20 ppm (+9.2 ± 11.3 mmHg) and 25-40 ppm (-5±2 mmHg) resulted in inconsistent effects on PaO2 (p = 0.48). Data on the effect of iNO on exercise capacity were too limited and inconsistent, but preliminary evidence suggests a possible benefit of iNO on pulmonary vascular resistance during exercise in severe COPD patients. Overall, the effects of acute dietary nitrate supplementation on BP may be of clinical relevance as an adjunct therapy and deserve further investigation in large sample size studies of COPD patients with and without cardiovascular comorbidities. iNO exerted inconsistent physiological effects, with the use of high doses posing safety risks.

To identify how variables such as exercise condition, supplementation strategy, participant characteristics and demographics, and practices that control oral microbiota diversity could modify the effect of inorganic nitrate ingestion (as nitrate salt supplements, beetroot juice, and nitrate-rich vegetables) on exercise performance, we conducted a systematic review with meta-analysis. Studies were identified in PubMed, Embase, and Cochrane databases. Eligibility criteria included randomized controlled trials assessing the effect of inorganic nitrate on exercise performance in healthy adults. To assess the variation in effect size, we used meta-regression models for continuous variables and subgroup analysis for categorical variables. A total of 123 studies were included in this meta-analysis, comprising 1705 participants. Nitrate was effective for improving exercise performance (standardized mean difference [SMD]: 0.101; 95% CI: 0.051, 0.151, P <0.001, I2 = 0%), although nitrate salts supplementation was not as effective (P = 0.629) as ingestion via beetroot juice (P <0.001) or a high-nitrate diet (P = 0.005). Practices that control oral microbiota diversity influenced the nitrate effect, with practices harmful to oral bacteria decreasing the ergogenic effect of nitrate. The ingestion of nitrate was most effective for exercise lasting between 2 and 10 min (P <0.001). An inverse dose-response relation between the fraction of inspired oxygen and the effect size (coefficient: -0.045, 95% CI: -0.085, -0.005, P = 0.028) suggests that nitrate was more effective in increasingly hypoxic conditions. There was a dose-response relation for acute administration (P = 0.049). The most effective acute dose was between 5 and 14.9 mmol provided ≥150 min prior to exercise (P <0.001). An inverse dose-response for protocols ≥2 d was observed (P = 0.025), with the optimal dose between 5 and 9.9 mmol·d-1 (P <0.001). Nitrate, via beetroot juice or a high-nitrate diet, improved exercise performance, in particular, in sessions lasting between 2 and 10 min. 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

Dietary nitrate supplementation has shown promising ergogenic effects on endurance exercise. However, at present there is no systematic analysis evaluating the effects of acute or chronic nitrate supplementation on performance measures during high-intensity interval training (HIIT) and sprint interval training (SIT). The main aim of this systematic review and meta-analysis was to evaluate the evidence for supplementation of dietary beetroot-a common source of nitrate-to improve peak and mean power output during HIIT and SIT. A systematic literature search was carried out following PRISMA guidelines and the PICOS framework within the following databases: PubMed, ProQuest, ScienceDirect, and SPORTDiscus. Search terms used were: ((nitrate OR nitrite OR beetroot) AND (HIIT or high intensity or sprint interval or SIT) AND (performance)). A total of 17 studies were included and reviewed independently. Seven studies applied an acute supplementation strategy and ten studies applied chronic supplementation. The standardised mean difference for mean power output showed an overall trivial, non-significant effect in favour of placebo (Hedges' g = -0.05, 95% CI -0.32 to 0.21, Z = 0.39, p = 0.69). The standardised mean difference for peak power output showed a trivial, non-significant effect in favour of the beetroot juice intervention (Hedges' g = 0.08, 95% CI -0.14 to 0.30, Z = 0.72, p = 0.47). The present meta-analysis showed trivial statistical heterogeneity in power output, but the variation in the exercise protocols, nitrate dosage, type of beetroot products, supplementation strategy, and duration among studies restricted a firm conclusion of the effect of beetroot supplementation on HIIT performance. Our findings suggest that beetroot supplementation offers no significant improvement to peak or mean power output during HIIT or SIT. Future research could further examine the ergogenic potential by optimising the beetroot supplementation strategy in terms of dosage, timing, and type of beetroot product. The potential combined effect of other ingredients in the beetroot products should not be undermined. Finally, a chronic supplementation protocol with a higher beetroot do

BACKGROUND: Dietary nitrate supplementation, usually in the form of beetroot juice, may improve exercise performance and endothelial function. We undertook a systematic review and meta-analysis to establish whether this approach has beneficial effects in people with respiratory disease. METHODS: A systematic search of records up to March 2021 was performed on PubMed, CINAHL, MEDLINE (Ovid), Cochrane and Embase to retrieve clinical trials that evaluated the efficacy of dietary nitrate supplementation on cardiovascular parameters and exercise capacity in chronic respiratory conditions. Two authors independently screened titles, abstracts and full texts of potential studies and performed the data extraction. RESULTS: After full-text review of 67 papers, eleven (two randomised controlled trials and nine crossover trials) involving 282 participants met the inclusion criteria. Three were single dose; seven short term; and one, the largest (n=122), done in the context of pulmonary rehabilitation. Pooled analysis showed that dietary nitrate supplementation reduced systolic blood pressure (BP), diastolic BP and mean arterial pressure (mean difference (95% CI), -3.39 mm Hg (-6.79 to 0.01); p=0.05 and -2.20 mm Hg (-4.36 to -0.03); p=0.05 and -4.40 mm Hg (-7.49 to -1.30); p=0.005, respectively). It was associated with increased walk distance in the context of pulmonary rehabilitation (standardised mean difference (95% CI), 0.47 (0.11 to 0.83), p=0.01), but no effect was identified in short-term studies (0.08 (-0.32 to 0.49). CONCLUSION: Dietary nitrate supplementation may have a beneficial effect on BP and augment the effect of pulmonary rehabilitation on exercise capacity. Short-term studies do not suggest a consistent benefit on exercise capacity. PROSPERO REGISTRATION NUMBER: CRD42019130123. © Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

This systematic review and meta-analysis of randomized controlled trials examined whether dietary nitrate supplementation attenuates exercise-induced muscle damage (EIMD) and is reported according to the PRISMA guidelines. Medline and SPORTDiscus databases were searched from inception to June 2020. Inclusion criteria were studies in adult humans consuming inorganic nitrate before and after exercise and that measured markers implicated in the etiology of EIMD (muscle function, muscle soreness, inflammation, myocellular protein efflux, oxidative stress, range of motion) <168 h post. The Cochrane Collaboration risk of bias two tool was used to critically appraise the studies; forest plots were generated with random-effects models and standardized mean differences (SMD). Nine studies were included in the systematic review and six in the meta-analysis. All studies were rated to have some concerns for risk of bias. All trials in the meta-analysis provided nitrate as beetroot juice, which accelerated isometric strength recovery 72 h post-exercise (SMD: 0.54, p = 0.01) and countermovement jump performance 24-72 h post-exercise (SMD range: 0.75-1.32, p < 0.03). Pressure pain threshold was greater with beetroot juice 48 (SMD: 0.58, p = 0.03) and 72 h post-exercise (SMD: 0.61, p = 0.02). Beetroot juice had no effect on markers of oxidative stress and creatine kinase (p > 0.05), but c-reactive protein was higher vs. placebo at 48 h post-exercise (SMD: 0.55, p = 0.03). These findings suggest that nitrate-rich beetroot juice may attenuate some markers of EIMD, but more large-scale controlled trials in elite athletes are needed.

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is a chronic inflammatory lung disease causing airflow obstruction from the lungs reducing exercise tolerance. It is one of the leading causes of respiratory dysfunction worldwide. Nitric Oxide (NO) may have a significant role in this inflammatory reaction to improve exercise capacity. AIM: To evaluate the effect of dietary nitrate ingestion for COPD patients. METHODS: We searched Scopus, PubMed, Cochrane, and Web of Science databases till August 2020 and updated the search in December 2020 using relevant keywords. All search results were screened for eligibility. We extracted the data from the included articles and pooled them as mean difference (MD) with a 95% confidence interval (CI), using Review Manager software (ver. 5.4). RESULTS: A pooled analysis from eight included trials showed no significant difference between dietary nitrate-rich beetroot juice and placebo in systolic blood pressure, diastolic blood pressure, heart rate, 6-min walk test, cycling ergometry endurance time, and maximum rate of oxygen consumption (VO2). On the other hand, nitrate-rich beetroot juice significantly increased the Borg Rating of Perceived Exertion (RPE) scale more than the placebo (MD = -0.77; 95% CI [0.18, 1.37], P = 0.01). CONCLUSION: There is no significant effect of nitrate-rich beetroot juice on cardiovascular events as systolic, diastolic blood pressure, and heart rate, or exercise performance as 6-min walk test, and cycling ergometry endurance time, or maximum rate of oxygen consumption (VO2). On the other hand, nitrate-rich beetroot juice improves the Borg Rating of Perceived Exertion (RPE) scale reflecting an increased exercise and physical activity level.

BACKGROUND/OBJECTIVES: Acute beetroot juice (BJ) nitrate supplementation may enhance agility and change of direction performance by increasing nitric oxide bioavailability and improving cognitive and skeletal muscle functions, thereby potentially attenuating post-sprint performance decrements. METHODS: We investigated whether a single dose of BJ improves agility immediately after repeated maximal sprinting compared with a placebo (PL) in soccer players. Twenty-one male soccer players (competitive players: n = 8; recreational players: n = 13) completed a double-blind randomised crossover trial. Participants ingested 70 mL of BJ or PL; afterwards, they performed three sets of 6 × 20-m all-out sprints. Agility outcomes included simple response time (SRT), choice response time (CRT), and change-of-direction speed (CODS). Non-parametric analyses (Wilcoxon signed-rank test with effect size r) were applied. RESULTS: Compared with PL, BJ improved CRT (BJ: 2.376 ± 0.255; PL: 2.534 ± 0.322; p < 0.001; r = 0.74; Z = -5.881) and CODS (BJ: 13.046 ± 1.512; PL: 13.651 ± 1.811; p < 0.001; r = 0.47; Z = -4.314). SRT was unchanged overall (BJ: 1.671 ± 0.195; PL: 1.707 ± 0.261; p = 0.185; r = 0.05; Z = -1.327). CONCLUSIONS: Under practical field-based conditions, acute BJ intake enhanced post-sprint agility and change-of-direction performance, particularly CRT and CODS.

BACKGROUND: Beetroot juice (BRJ) supplementation has the potential to enhance the effects of blood flow restriction (BFR) training in improving muscle strength and fatigue resistance; however, evidence supporting their combined effects remains limited. This study investigated whether BRJ supplementation enhances the effects of BFR training on muscle strength and fatigue resistance. METHODS: This randomized, double-blind, placebo-controlled trial included 20 male university students from the School of Sports, who were randomly assigned to a BFR group (n = 10, age: 21.9 ± 1.7 years) or a BFR + BRJ group (n = 10, age: 21.8 ± 1.5 years; nitrate: 8 mmol/day). Participants completed a one-week BRJ pre-supplementation phase followed by a four-week bilateral knee extensor/flexor BFR training program (40% limb occlusion pressure, 30% of peak torque load), performed three times per week. Knee extensor and flexor strength (at 60°/s, 180°/s, and MVIC) and countermovement jump (CMJ) performance were assessed using an isokinetic dynamometer and a force plate pre- and post-intervention. RESULTS: Both the four-week BFR and BFR+BRJ interventions significantly increased the relative peak torque of the knee extensors/flexors at 60°/s (Left: ppre-post = 0.23, d = -0.89, ηp²Time = 0.775; Right: ppre-post = 0.017, d = -0.63, ηp²Time = 0.744), 180°/s (Left: ppre-post = 0.028, d = -1.32, ηp²Time = 0.319; Right: ppre-post = 0.007, d = -1.48, ηp²Time = 0.822), and MVIC (Left: ppre-post = 0.007, d = -0.11, ηp²Time = 0.825; Right: ppre-post = 0.009, d = -1.31, ηp²Time = 0.842). They also improved the torque of the knee extensors in both the left and right legs during the 100-repetition maximal voluntary contraction test at 90°/s, with both initial (first 20 reps) and final (last 20 reps) values significantly increased (Left: ppre-post = 0.029, d = -0.96, ηp²Time = 0.612; Right: ppre-post = 0.007, d = -1.21, ηp²Time = 0.725). The CMJ test showed significant improvements in fatigued bilateral CMJ height (ppre-post = 0.048, d = -0.534, ηp²Time = 0.556), peak force (ppre-post = 0.047, d = -0.913, ηp²Time = 0.444), and rate of force development (RFD; ppre-post = 0.044, d = -0.902, ηp²Time = 0.6

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterised by chronic hyperglycaemia, whereas obesity is a major risk factor which increases morbidity and mortality. Treatments that alter white adipose tissue to express a metabolically active brown adipose phenotype in rats may offer adjunct treatment in people with T2DM. To investigate whether inorganic nitrate supplementation from beetroot juice (BJ) alters brown adipose tissue (BAT) fat fraction and activation in humans. Thirteen older adults with T2DM (glycated haemoglobin [HbA1c]: 58 ± 13 mmol·mol-1 and body mass index: 29.1 ± 3.1 kg·m-2) completed a double-blind, randomised, balanced and placebo-controlled crossover study. Outcome measures (including BAT fat fraction; activation; plasma [nitrate] and [nitrite]) were assessed before and after 14-day of 140 mL·day-1 BJ containing inorganic nitrate (∼12.4 mmol·L1) or a placebo (∼0.1 mmol·L1). Magnetic resonance imaging (MRI) and infrared thermography (IRT) were performed to image supraclavicular BAT following a rested cooling protocol, consisting of 60-min exposure via a cold water (8.1 ± 1.2°C) perfused jacket. Respiratory parameters, including respiratory exchange ratio [RER] and mean skin temperature, were measured during the cooling protocol to confirm participants were not shivering. BJ significantly increased venous plasma [nitrate] and [nitrite] versus placebo (p < 0.001) but did not affect BAT fat fraction (p = 0.650) or activation (p = 0.152). Cooling significantly reduced mean skin temperature in BJ (-0.8 ± 0.7°C) and placebo (-0.6 ± 0.6°C) (p < 0.001) and RER remained representative of nonshivering thermogenesis throughout (0.88 ± 0.05 a.u.). 14-day of nitrate supplementation did not increase BAT fat fraction or activation in older adults with T2DM. © 2026 The Author(s). European Journal of Sport Science published by Wiley‐VCH GmbH on behalf of European College of Sport Science.

This randomized controlled crossover trial compared the short-term effects of creatine (CR) and beetroot juice (BJ) on resistance training performance and physiological responses across ∼72 h supplementation period. Eleven novice resistance-trained men completed bench press (BP) and back squat (BS) sets at 60-80% 1RM under CR, BJ, and placebo (PLA) conditions. Performance outcomes, intramuscular-oxygen-saturation (SmO2), peak heart rate (HR), and heart rate variability (HRV) were assessed. Individual modulation prevalence was also determined. CR significantly improved repetition performance at 80% 1RM in BP (d = 1.33) compared to PLA. Both CR and BJ produced moderate-to-very large effects on velocity with superior effect using BJ (d = 1.40-2.82 vs. PLA). Higher SmO2 (d = 1.74-2.9), lower peak HR (d = 0.83-2.74), and more favourable autonomic recovery (e.g. RMSSD: d = 0.91-2.99) were observed with BJ compared to both PLA and CR. Modulation analysis indicated greater proportions of meaningful individual adaptations, following BJ compared to CR. Overall, CR appeared to preferentially enhance mechanical performance, whereas BJ seemed to provide broader cardiometabolic and autonomic benefits.

Increasing dietary nitrate (NO3-) through beetroot juice (BRJ) supplementation elicits acute ergogenic benefits. However, it is unknown whether chronic NO3- supplementation can enhance resistance training (RT) adaptations in middle-aged and older individuals. Therefore, we sought to determine whether 12 wk of combined RT and NO3- supplementation enhanced hypertrophic, vascular, strength, and skeletal muscle angiogenesis adaptations in this population. Twenty-eight apparently healthy, untrained men (M) and women (W) (56 ± 7 yr old and 29.1 ± 5.3 kg/m2 body mass index) completed 12 wk of supervised full-body RT (2×/wk) while ingesting either BRJ (140 mL daily, providing 800 mg NO3-; n = 14 with 7 M/7 W) or NO3--depleted BRJ placebo (PLA; n = 14 with 7 M/7 W). Participants underwent a whole body dual-energy X-ray absorptiometry scan, right mid-thigh ultrasonography for muscle imaging, right leg popliteal artery flow-mediated dilation (FMD) assessments, a biopsy of the right mid-thigh vastus lateralis, and strength testing before and following the 12-wk intervention. Biopsy analyses included a NO3-/nitrite (NOx) fluorometric assay, immunoblotting for proteins involved in angiogenesis, and immunohistochemistry to quantify fiber type-specific capillaries and cross-sectional areas. Muscle NOx values did not significantly change: +15.4% in BRJ (P = 0.073) and +7.8% (P = 0.514) in PLA. Both groups significantly improved measures related to muscle hypertrophy, strength, and FMD. However, no significant group × time interactions were observed for whole body lean mass, mid-thigh muscle cross-sectional area, popliteal artery FMD outcomes, or histological or molecular markers. In conclusion, these preliminary data on a limited number of participants indicate that BRJ supplementation does not enhance RT adaptations in middle-aged and older adults.NEW & NOTEWORTHY Results from this study suggest that 12 wk of dietary nitrate supplementation does not significantly alter skeletal muscle hypertrophic, strength, or vascular outcomes in previously untrained middle-aged and older adults who performed resistance training.

PURPOSE: Increasing nitric oxide bioavailability via nitrate (NO 3- ) ingestion enhances muscle contractility, which may be due to phosphorylation of the regulatory light chain of myosin. If so, there should be an interaction between NO 3- supplementation and post activation twitch potentiation, which acts via the same pathway. METHODS: A double-blind, placebo-controlled, randomized crossover study was conducted to determine the influence of dietary NO 3- on the contractile properties of the triceps brachii (60%-70% fast-twitch, or type II) and triceps surae (60%-70% slow-twitch, or type I) muscles of healthy young men ( n = 14). Participants were studied after acute ingestion of 2.2 mL/kg of beetroot juice either containing or lacking 200 µmol/kg of NO 3- , with neuromuscular electrical stimulation used to determine muscle function. RESULTS: NO 3- supplementation did not alter unpotentiated or potentiated peak twitch torque or the maximal rates of torque development or relaxation in either muscle group. On the other hand, NO 3- ingestion resulted in significant changes in the torque-frequency relationship of both the triceps brachii ( P = 0.019) and the triceps surae ( P < 0.001). This was due to a leftward shift of this sigmoidal relationship in the triceps brachii, but a rightward shift in the triceps surae. CONCLUSIONS: We conclude that dietary NO 3- has opposing effects on the contractile properties of fast and slow human muscles, which could be due to differential changes in Ca 2+ sensitivity. However, potentiation was unaltered, suggesting that this occurs independently of changes in regulatory light chain phosphorylation. Additional research will be required to determine the underlying biochemical mechanisms.

BACKGROUND: Skeletal muscle fatigue reflects the interaction of metabolic demand, contractile efficiency, and oxygen delivery, processes highly dependent on microvascular function. Prolonged ischemia induces transient microvascular dysfunction that can impair fatigue resistance. Dietary nitrate, abundant in beetroot juice, enhances nitric oxide bioavailability and vascular function, but whether it mitigates ischemia-induced decrements in microvascular reactivity and fatigue resistance remains unclear. OBJECTIVES: To determine whether a single oral dose of nitrate-rich beetroot juice (NR-BJ) protects against prolonged ischemia-induced impairments in microvascular function and fatigue resistance in a sex-dependent manner. METHODS: Sixteen healthy adults (8 males, 8 females; 20-40 y) completed a randomized, double-blind, crossover trial with NR-BJ (∼10 mmol nitrate) or nitrate-depleted beetroot juice (ND-BJ, ∼0.34 mmol nitrate). Two hours postingestion, participants underwent 20 min of forearm arterial occlusion to induce microvascular dysfunction. Microvascular reactivity was assessed by near-infrared spectroscopy (tissue oxygen saturation resaturation slope), and fatigue resistance was determined during 50 maximal isokinetic wrist flexion-extension contractions. Serum nitrate and nitrite were measured by high-performance liquid chromatography. RESULTS: Circulating nitrate and nitrite increased significantly after NR-BJ in both males and females. Prolonged ischemia reduced the tissue oxygen saturation resaturation slope in both sexes under the ND-BJ condition. NR-BJ attenuated this decline in females but not in males. In males, ischemia reduced total work and early-phase work (the first one-third of repetitions) under ND-BJ, effects that were prevented by NR-BJ. Fatigue resistance was preserved in females across conditions. CONCLUSIONS: Acute dietary nitrate supplementation preserves fatigue resistance in males despite persistent microvascular dysfunction, whereas in females it attenuates ischemia-induced microvascular impairment without affecting fatigue resistance. These findings support sex-specific protective effects of dietary nitrate against transient vascul

Dietary interventions are recommended as part of hypertension (HTN) treatment. Sodium reduction has proven effective, however supplements of potassium and/or nitrate are likely also of importance. We aimed to test how these three dietary components affect blood pressure (BP) individually and in combination in patients with HTN. A double-blind randomized controlled trial of 90 participants with HTN was conducted. Participants were randomized to eight groups receiving a hand-out diet and different combinations of supplementation of sodium chloride (130 mmol/day), potassium chloride (40 mmol/day) and beetroot juice (BRJ) with nitrate (13 mmol/day) or for each a matching placebo. The intervention lasted one week. 24 h BP, blood samples and 24 h urine collection were conducted before and after. We found a strong association between change in BP and sodium reduction (p < 0.0001). The change in systolic BP in the low-sodium groups was -7 mmHg (95% CI -9;-5) and no change was found in the high-sodium groups. We found a BP reduction in the low-potassium vs. the high-potassium groups (p = 0.03). Nitrate supplementation was not related to change in BP (p = 0.31). Plasma aldosterone and aldosterone-to-renin ratio (ARR) were associated to the change in BP in the low-sodium groups. In conclusion, in this one week intervention we found sodium reduction to be the important dietary alteration in matters of lowering BP. BRJ with nitrate and potassium chloride supplements did not assist in decreasing BP during this short-time intervention. Measuring ARR might be relevant in a clinical setting to predict the BP effect of sodium reduction. URL: https://www.clinicaltrialsregister.eu . Unique identifier: 2021-003407-17. © 2025. The Author(s), under exclusive licence to Springer Nature Limited.

Dietary nitrate ([Formula: see text]), a source of nitric oxide (NO), enhances muscle contractility in numerous populations, but it is still unclear whether young women also benefit. The efficacy of [Formula: see text] supplementation might vary with menstrual cycle phase, due to lower endogenous NO bioavailability when estradiol (E2) is low. Using a double-blind, placebo-controlled, crossover design, we determined the effects of acute ingestion of 200 μmol/kg of [Formula: see text] (from concentrated beetroot juice) or placebo on muscle function in 12 normally menstruating women during the early follicular (EF) and late follicular (LF) phases of their cycle. Muscle function was determined through maximal knee extensions on an isokinetic dynamometer and electrical stimulation of the quadriceps, with menstrual phase confirmed through plasma hormone measurement. E2 concentrations were significantly lower in EF versus LF (220 ± 90 vs. 583 ± 260 pM; P < 0.001), whereas progesterone levels did not differ. Despite this, dietary [Formula: see text] had no effect on maximal muscle power or velocity during either phase. Dietary [Formula: see text] also had no effect on unpotentiated or potentiated peak twitch torque, rate of torque development (RTD), rate of relaxation (RR), or the torque frequency relationship during either phase. However, the RTD was 2%-8% greater in the LF versus EF phase, especially in the unpotentiated state (P < 0.01). The RR was also 9% slower in the LF versus EF phase (P < 0.05). Variations in E2 during the menstrual cycle seem to subtly influence muscle contractile function. Acute [Formula: see text] supplementation, on the contrary, has no apparent effect on muscle contractility in young women.NEW & NOTEWORTHY We determined the effects of dietary [Formula: see text] on muscle contractile function during the early follicular (EF) and late follicular (LF) phases of the menstrual cycle. Although [Formula: see text] supplementation had no impact on muscle contractility, during electrically evoked twitches, the rate of torque development was greater, and the rate of relaxation was slower, in the LF phase. These findings enhance our understanding of

We investigated the impact of short-term dietary nitrate supplementation on sympathetic neural responses to isometric exercise in postmenopausal women. Ten healthy women aged 64 ± 2 (SD) yr participated in this randomized, placebo-controlled, double-blind, and crossover study. All participants underwent 2-wk beetroot juice (BRJ: 800 mg nitrate/day) and placebo (nitrate-depleted BRJ) interventions with ≥14 days of washout. Before and after each intervention, participants performed static handgrip (SHG) at 40% of maximum voluntary contraction until fatigue, followed by 2-min post-exercise circulatory occlusion (PECO) with an upper arm cuff inflated to 250 mmHg to isolate metaboreflex activation. Heart rate (electrocardiogram), blood pressure (finger photoplethysmography), and muscle sympathetic nerve activity (MSNA; microneurography) were continuously measured. BRJ increased the time to fatigue more than placebo (Δ79 ± 67 vs. Δ9 ± 74 s, P = 0.03), which was correlated with decreases in MSNA burst frequency, total activity, and burst incidence at the first 30 s of SHG when predominately mechanoreflex activation occurs (r = -0.65, -0.62, and -0.68, respectively, all P < 0.05). However, BRJ did not alter MSNA responses to peak SHG and PECO. Subsequently, we added four postmenopausal women who finished the BRJ intervention only and categorized all participants into early (n = 6) and normal menopause (n = 8). The early, but not normal, menopause group showed decreases in MSNA burst frequency and incidence at the first 30 s of SHG after the BRJ intervention (both P < 0.05). Collectively, nitrate supplementation prolonged the time to fatigue during SHG, and this prolongation was likely associated with attenuated sympathetic neural responses to mechanoreflex activation in postmenopausal women, especially those with early menopause.NEW & NOTEWORTHY Menopause induces augmented sympathetic responses to exercise, which may be related to the risk of exercise intolerance. Here, we found that short-term dietary nitrate supplementation in postmenopausal women prolonged the time to fatigue during static handgrip, and the prolongation was associated with suppressed MSNA responses a

The physiological and exercise performance adaptations to sprint interval training (SIT) may be modified by dietary nitrate ([Formula: see text]) supplementation. However, it is possible that different types of [Formula: see text] supplementation evoke divergent physiological and performance adaptations to SIT. The purpose of this study was to compare the effects of 4-wk SIT with and without concurrent dietary [Formula: see text] supplementation administered as either [Formula: see text]-rich beetroot juice (BR) or potassium [Formula: see text] (KNO3). Thirty recreationally active subjects completed a battery of exercise tests before and after a 4-wk intervention in which they were allocated to one of three groups: 1) SIT undertaken without dietary [Formula: see text] supplementation (SIT); 2) SIT accompanied by concurrent BR supplementation (SIT + BR); or 3) SIT accompanied by concurrent KNO3 supplementation (SIT + KNO3). During severe-intensity exercise, V̇o2peak and time to task failure were improved to a greater extent with SIT + BR than SIT and SIT + KNO3 ( P < 0.05). There was also a greater reduction in the accumulation of muscle lactate at 3 min of severe-intensity exercise in SIT + BR compared with SIT + KNO3 ( P < 0.05). Plasma [Formula: see text] concentration fell to a greater extent during severe-intensity exercise in SIT + BR compared with SIT and SIT + KNO3 ( P < 0.05). There were no differences between groups in the reduction in the muscle phosphocreatine recovery time constant from pre- to postintervention ( P > 0.05). These findings indicate that 4-wk SIT with concurrent BR supplementation results in greater exercise capacity adaptations compared with SIT alone and SIT with concurrent KNO3 supplementation. This may be the result of greater NO-mediated signaling in SIT + BR compared with SIT + KNO3. NEW & NOTEWORTHY We compared the influence of different forms of dietary nitrate supplementation on the physiological and performance adaptations to sprint interval training (SIT). Compared with SIT alone, supplementation with nitrate-rich beetroot juice, but not potassium [Formula: see text], enhanced some physiological adaptations to training.

Background: Findings show that beetroot-derived nitrates can improve endurance, oxygen efficiency, muscular power, recovery and cardiovascular function, particularly in recreationally active or moderately trained individuals. However, results are mixed in elite athletes, likely due to their already optimized nitric oxide utilization. Cognitive function is a crucial aspect of athletic performance enabling athletes to adapt to dynamic environments and execute skills effectively, but evidence for cognitive benefits of nitrate-rich beetroot supplementation is limited and inconsistent. The combination of improved physical activity and cognitive functions contribute to overall healthy aging and extending life expectancy. This highlights the synergistic role of nutrition, exercise and mental agility in promoting long-term well-being. Methods: The literature review was conducted to summarize and systematize existing evidence on beetroot juice supplementation on physical performance and cognitive function in both, healthy adult population and athletes. Results: Overall, beetroot supplementation demonstrates strong potential as a natural ergogenic aid for enhancing physical performance, but current evidence on cognitive improvement remains inconclusive. Conclusions: Further research, particularly involving female or elite athletes, is needed to establish clear recommendations of beetroot juice supplementation as a supportive element of exercise capacity and cognitive abilities contributing to maintaining health and thus healthy aging.

Background: Beetroot juice, the most commonly used route of dietary nitrate supplementation, is theorized to enhance physical performance. However, its effects on different aspects of physical performance, different populations, and optimal supplementation strategies remain controversial. The purpose of this study was to investigate the effects of beetroot juice (nitrate-rich) on physical performance, to compare its effects between professional athletes and non-athletes (healthy individuals), and to determine the optimal supplementation strategy. Methods: A systematic search was conducted on the Web of Science, Embase, PubMed, Cochrane Database, SPORTDiscus, Scopus, and CINAHL databases. Reviewers conducted study screening and selection, data extraction, and assessment of methodological quality using the AMSTAR 2 tool. Fifteen meta-analyses were included in this Umbrella Review. A narrative and quantitative synthesis was performed. Standardized mean differences (SMD) and 95% confidence intervals (CI) were reported. Results: (1) Beetroot juice significantly improved muscle strength (SMD = 0.08, p < 0.001), but the effect size was negligible. (2) Aerobic Endurance: Beetroot juice significantly improved VO2max (SMD = 0.16, p = 0.033) in healthy adults; however, the effect size was negligible. (3) Lactate Tolerance: beetroot juice significantly improved TTE (SMD = 0.25, p = 0.034) and YO-YOIR1 (SMD = 0.27, p = 0.049) performance in healthy adults, but the effect size was small. (4) Subgroup analyses revealed significant population differences: professional athletes showed significant muscular strength benefits (SMD = 0.27, p = 0.007), whereas non-athletes had more pronounced aerobic endurance improvements (SMD = 0.26, p < 0.001), but the effect size was small. (5) Nitrate supplementation timing and dose-response analysis revealed that nitrate supplementation, whether administered 2-3 h before exercise or over a prolonged period (≥3 days), produces a significant enhancement in physical performance (p < 0.01). Notably, acute improvement only has a small effect size (SMD = 0.20), while the impact of chronic supplementation is essentially negligible (SMD = 0.13). A dosa

AIMS: It has been suggested that nitrate-rich beetroot juice (BRJ) reduces blood pressure (BP) in various populations. We aimed to investigate the effect of BRJ on BP in adults with hypertension according to the European Society of Hypertension Guidelines (clinical BP ≥ 140/≥ 90 mmHg) and whether BRJ can be considered as an adjunct to hypertension drug treatment, by conducting a meta-analysis of randomized controlled trials. DATA SYNTHESIS: PubMed, SCOPUS, Medline Ovid, Cinahl, Cochrane Library and Web of Science were searched from inception until April 13, 2024 to identify randomized controlled trials of BRJ versus placebo, water, or no intake. Risk of bias was assessed using a standardized appraisal instrument from the Swedish Agency for Health Technology and Assessment of Social Services, which is based on the Cochrane risk-of-bias tool for randomized trials. The pooled BP effect size was calculated using random effects models and meta-regression. Certainty of evidence was assessed using GRADE. Eleven trials (349 patients) were included. BRJ yielded a significant reduction in clinical systolic BP compared with placebo mean difference (MD) -5.31 mmHg (95% CI -7.46, -3.16; I2 = 64%, GRADE ⊕⊕OO). There was no significant effect on clinical diastolic BP or 24-h BP outcomes, and the heterogeneity was moderate to high. CONCLUSIONS: Daily ingestion of 200-800 mg of nitrate from BRJ may reduce clinical systolic BP in hypertensive individuals with no sign of development of tolerance. Certainty of evidence is low, and results should be interpreted with caution.

Poor oral health can impact an individual's ability to eat and has been associated with an increased risk of non-communicable diseases. While the benefits of nitrate consumption on oral health were first proposed more than 20 years ago, no systematic review has been published examining effects of dietary nitrate on oral health. This systematic review investigated the effects of dietary nitrate on markers of oral health in vivo in randomized controlled trials (RCTs). Five databases (PubMed, The Cochrane Library, CINAHL, MEDLINE, and SPORTDiscus) were searched from inception until March 2023. Nine articles reporting data on 284 participants were included. Dietary nitrate was provided via beetroot juice in most studies. The duration of the interventions ranged from one day to six weeks. Dietary nitrate supplementation increased the relative abundance of several individual bacterial genera including Neisseria and Rothia. Dietary nitrate supplementation increased salivary pH and decreased salivary acidification following consumption of a sugar-sweetened beverage. Furthermore, dietary nitrate supplementation resulted in a decrease in the gingival inflammation index. The results of this systematic review suggest that dietary nitrate could represent a potential nutritional strategy to positively modify oral health by impacting the oral microbiome, altering salivary pH, and minimizing gingival inflammation.

Dietary supplements are widely used among athletes, and soccer players are no exception. Nevertheless, evidence supporting the use of dietary supplements aiming to enhance performance in soccer is somewhat contradictory, scarce, or even nonexistent. Thus, the present study aimed to systematically review and synthesize the effects of dietary supplements on athletic performance (e.g. distance covered, sprinting, jump performance) in elite soccer players. Studies enrolling highly trained, elite, and world-class soccer players using dietary supplements were searched in MEDLINE/PubMed, Web of Science, Scopus, and EBSCO databases in June 2022. In total, 1043 studies were identified, and 18 met the eligibility criteria. The studies evaluated the impacts on athletic performance of several dietary supplements, including caffeine, creatine, protein, beverages with carbohydrates and electrolytes, tart cherry juice, nitrate-rich beetroot juice, sodium bicarbonate with minerals, yohimbine, and a proprietary nutraceutical blend. Caffeine supplementation in doses between 3 and 6 mg/kg of body mass may improve jump height and sprint ability, particularly in female players, but individual response to caffeine must be considered. Creatine may improve sprint, agility, and in female players, jump performance. Protein supplementation can improve sprint and jump performance between matches, especially if protein ingested from food is not up to recommendations. Beverages containing carbohydrates and electrolytes can be used as part of the strategies to achieve carbohydrate intake during training and match-days but used alone do not benefit athletic performance. Tart cherry juice might be useful for maintaining athletic performance after matches that produce higher force loss and exercise-induced muscle damage, although polyphenols from the diet might attenuate the effects of tart cherry supplementation. Nitrate-rich beetroot concentrate can attenuate performance decrease in the days following matches. Further investigation with sodium bicarbonate alone is necessary, as supplementation protocols with elite players included other substances. Finally, the available data does not support

Comment in J Strength Cond Res. 2023 Jun 1;37(6):e404. doi: 10.1519/JSC.0000000000004572. Anderson, OK, Martinez-Ferran, M, Lorenzo-Calvo, J, Jiménez, SL, and Pareja-Galeano, H. Effects of nitrate supplementation on muscle strength and mass: a systematic review. J Strength Cond Res 36(12): 3562-3570, 2022-This systematic review examines the effect of dietary nitrate supplementation (SUP) on muscle strength and hypertrophy when combined with physical exercise. The databases PubMed, Web of Science, and MEDLINE were searched for full-text articles published between January 2000 and June 2020. For inclusion, studies had to report on the effects of SUP administered as acute or chronic doses together with a standardized exercise protocol on muscle strength and hypertrophy compared with placebo in healthy adults who were sedentary, physically active, or professional athletes. Twelve studies (1,571 subjects) were finally selected. In 5 studies, the SUP regime was acute, and in 7, it was chronic. SUP was nitrate-rich beetroot juice in 9 studies, a potassium nitrate capsule in 1, and increased dietary nitrate in 2. Ingested nitrate was 64-1,200 mg. Of the 12 studies, 6 observed an ergogenic effect of SUP compared with placebo. These findings indicate that muscle strength gains are possible provided the dose, format, frequency, period, and exercise test are appropriate. Best results were observed with a minimum acute dose of 400 mg of nitrate provided as beetroot juice/shot taken 2-2.5 hours before exercise involving low- and high-intensity muscle contractions. This SUP regime seems to improve muscle efficiency in terms of reduced phosphocreatine and energy costs (P-magnetic resonance spectroscopy) and improved time to exhaustion.