scholarly journals No Effect of Beetroot Juice Supplementation on 100-m and 200-m Swimming Performance in Moderately Trained Swimmers

2019 ◽  
Vol 14 (6) ◽  
pp. 706-710 ◽  
Author(s):  
Ozcan Esen ◽  
Ceri Nicholas ◽  
Mike Morris ◽  
Stephen J. Bailey
Keyword(s):  
Blood Pressure ◽  
Swimming Performance ◽  
Time Trial ◽  
Upper Body ◽  
Beetroot Juice ◽  
Nitrite Concentration ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Nitrate Supplementation ◽  
Plasma Nitrite

Purpose: Dietary nitrate supplementation has been reported to improve performance in kayaking and rowing exercise, which mandate significant recruitment of the upper-body musculature. Because the effect of dietary nitrate supplementation on swimming performance is unclear, the purpose of this study was to assess the effect of dietary nitrate supplementation on 100-m and 200-m swimming freestyle time-trial (TT) performance. Methods: In a double-blind, randomized crossover design, 10 moderately trained swimmers underwent 2 separate 3-d supplementation periods, with a daily dose of either 140 mL nitrate-rich (∼800 mg/d nitrate) or nitrate-depleted (PLA) beetroot juice (BRJ). After blood sampling on day 3, the swimmers performed both 200-m and 100-m freestyle swimming TTs, with 30 min recovery between trials. Results: Plasma nitrite concentration was greater after BRJ relative to PLA consumption (432 [203] nmol/L, 111 [56] nmol/L, respectively, P = .001). Systolic blood pressure was lowered after BRJ compared with PLA supplementation (114 [10], 120 [10] mm Hg, respectively P = .001), but time to complete the 200-m (BRJ 152.6 [14.1] s, PLA 152.5 [14.1] s) and 100-m (BRJ 69.5 [7.2] s, PLA 69.4 [7.4] s) freestyle swimming TTs was not different between BRJ and PLA (P > .05). Conclusions: Although 3 d of BRJ supplementation increased plasma nitrite concentration and lowered blood pressure, it did not improve 100-m and 200-m swimming TT performance. These results do not support an ergogenic effect of nitrate supplementation in moderately trained swimmers, at least for 100-m and 200-m freestyle swimming performance.

scholarly journals The Effect of Dietary Nitrate Supplementation on Physiology and Performance in Trained Cyclists

2017 ◽  
Vol 12 (5) ◽  
pp. 684-689 ◽  
Author(s):  
Joseph A. McQuillan ◽  
Deborah K. Dulson ◽  
Paul B. Laursen ◽  
Andrew E. Kilding
Keyword(s):  
Time Trial ◽  
Crossover Design ◽  
Moderate Intensity ◽  
Beetroot Juice ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Performance Time ◽  
Exercise Economy ◽  
Nitrate Supplementation ◽  
And Performance

Purpose:To determine the effect of dietary nitrate (NO3 –) supplementation on physiology and performance in well-trained cyclists after 6–8 d of NO3 – supplementation.Methods:Eight competitive male cyclists (mean ± SD age 26 ± 8 y, body mass 76.7 ± 6.9 kg, VO2peak 63 ± 4 mL · kg–1 · min–1) participated in a double-blind, placebo-controlled, crossover-design study in which participants ingested 70 mL of beetroot juice containing ~4 mmol NO3 – (NIT) or a NO3 –-depleted placebo (PLA), each for 8 d. Replicating pretreatment measures, participants undertook an incremental ramp assessment to determine VO2peak and first (VT1) and second (VT2) ventilatory thresholds on d 6 (NIT6 and PLA6), moderate-intensity cycling economy on d 7 (NIT7 and PLA7), and a 4-km time trial (TT) on d 8 (NIT8 and PLA8).Results:Relative to PLA, 6 d of NIT supplementation produced unclear effects for VO2peak (mean ± 95% confidence limit: 1.8% ± 5.5%) and VT1 (3.7% ± 12.3%) and trivial effects for both VT2 (–1.0% ± 3.0%) and exercise economy on d 7 (–1.0% ± 1.6%). However, effects for TT performance time (–0.7% ± 0.9%) and power (2.4% ± 2.5%) on d 8 were likely beneficial.Conclusions:Despite mostly unclear outcomes for standard physiological determinants of performance, 8 d of NO3 – supplementation resulted in likely beneficial improvements to 4-km TT performance in well-trained male endurance cyclists.

scholarly journals Acute beetroot juice supplementation on sympathetic nerve activity: a randomized, double-blind, placebo-controlled proof-of-concept study

2017 ◽  
Vol 313 (1) ◽  
pp. H59-H65 ◽  
Author(s):  
Karambir Notay ◽  
Anthony V. Incognito ◽  
Philip J. Millar
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Sympathetic Outflow ◽  
Beetroot Juice ◽  
Proof Of Concept ◽  
Burst Frequency ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Nitrate Supplementation ◽  
Central Sympathetic Outflow

Acute dietary nitrate ([Formula: see text]) supplementation reduces resting blood pressure in healthy normotensives. This response has been attributed to increased nitric oxide bioavailability and peripheral vasodilation, although nitric oxide also tonically inhibits central sympathetic outflow. We hypothesized that acute dietary [Formula: see text] supplementation using beetroot (BR) juice would reduce blood pressure and muscle sympathetic nerve activity (MSNA) at rest and during exercise. Fourteen participants (7 men and 7 women, age: 25 ± 10 yr) underwent blood pressure and MSNA measurements before and after (165–180 min) ingestion of 70ml high-[Formula: see text] (~6.4 mmol [Formula: see text]) BR or [Formula: see text]-depleted BR placebo (PL; ~0.0055 mmol [Formula: see text]) in a double-blind, randomized, crossover design. Blood pressure and MSNA were also collected during 2 min of static handgrip (30% maximal voluntary contraction). The changes in resting MSNA burst frequency (−3 ± 5 vs. 3 ± 4 bursts/min, P = 0.001) and burst incidence (−4 ± 7 vs. 4 ± 5 bursts/100 heart beats, P = 0.002) were lower after BR versus PL, whereas systolic blood pressure (−1 ± 5 vs. 2 ± 5 mmHg, P = 0.30) and diastolic blood pressure (4 ± 5 vs. 5 ± 7 mmHg, P = 0.68) as well as spontaneous arterial sympathetic baroreflex sensitivity ( P = 0.95) were not different. During static handgrip, the change in MSNA burst incidence (1 ± 8 vs. 8 ± 9 bursts/100 heart beats, P = 0.04) was lower after BR versus PL, whereas MSNA burst frequency (6 ± 6 vs. 11 ± 10 bursts/min, P = 0.11) as well as systolic blood pressure (11 ± 7 vs. 12 ± 8 mmHg, P = 0.94) and diastolic blood pressure (11 ± 4 vs. 11 ± 4 mmHg, P = 0.60) were not different. Collectively, these data provide proof of principle that acute BR supplementation can decrease central sympathetic outflow at rest and during exercise. Dietary [Formula: see text] supplementation may represent a novel intervention to target exaggerated sympathetic outflow in clinical populations. NEW & NOTEWORTHY The hemodynamic benefits of dietary nitrate supplementation have been attributed to nitric oxide-mediated peripheral vasodilation. Here, we provide proof of concept that acute dietary nitrate supplementation using beetroot juice can decrease muscle sympathetic outflow at rest and during exercise in a normotensive population. These results have applications for targeting central sympathetic overactivation in disease.

scholarly journals Effect of nitrate supplementation on hepatic blood flow and glucose homeostasis: a double-blind, placebo-controlled, randomized control trial

2016 ◽  
Vol 311 (3) ◽  
pp. G356-G364 ◽  
Author(s):  
Anthony I. Shepherd ◽  
Daryl P. Wilkerson ◽  
Jon Fulford ◽  
Paul G. Winyard ◽  
Nigel Benjamin ◽  
...  
Keyword(s):  
Blood Flow ◽  
Portal Vein ◽  
Older Adult ◽  
Plasma Glucose ◽  
Beetroot Juice ◽  
Nitrite Concentration ◽  
Double Blind ◽  
C Peptide ◽  
Nitrate Supplementation ◽  
Plasma Nitrite

Nitric oxide alters gastric blood flow, improves vascular function, and mediates glucose uptake within the intestines and skeletal muscle. Dietary nitrate, acting as a source of nitric oxide, appears to be a potential low-cost therapy that may help maintain glucose homeostasis. In a randomized, double-blind, placebo-controlled crossover study, 31 young and older adult participants had a standardized breakfast, supplemented with either nitrate-rich beetroot juice (11.91 mmol nitrate) or nitrate-depleted beetroot juice as placebo (0.01 mmol nitrate). MRI was used to assess apparent diffusion coefficient (ADC), portal vein flux, and velocity. Plasma glucose, incretin, and C-peptide concentrations and blood pressure were assessed. Outcome variables were measured at baseline and hourly for 3 h. Compared with a placebo, beetroot juice resulted in a significant elevation in plasma nitrate and plasma nitrite concentration. No differences were seen for the young or older adult cohorts between placebo and beetroot juice for ADC, or portal vein flux. There was an interaction effect in the young adults between visits for portal vein velocity. Nitrate supplementation did not reduce plasma glucose, active GLP-1, total GLP-1, or plasma C-peptide concentrations for the young or older adult cohorts. Despite a significant elevation in plasma nitrite concentration following an acute dose of (11.91 mmol) nitrate, there was no effect on hepatic blood flow, plasma glucose, C-peptide, or incretin concentration in healthy adults.

Effects of short-term dietary nitrate supplementation on blood pressure, O2 uptake kinetics, and muscle and cognitive function in older adults

2013 ◽  
Vol 304 (2) ◽  
pp. R73-R83 ◽  
Author(s):  
James Kelly ◽  
Jonathan Fulford ◽  
Anni Vanhatalo ◽  
Jamie R. Blackwell ◽  
Olivia French ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Older Adults ◽  
Cognitive Function ◽  
Metabolic Response ◽  
Treadmill Walking ◽  
Beetroot Juice ◽  
Dietary Nitrate ◽  
Resting Blood Pressure ◽  
Nitrate Supplementation ◽  
Plasma Nitrite

Dietary nitrate (NO3−) supplementation has been shown to reduce resting blood pressure and alter the physiological response to exercise in young adults. We investigated whether these effects might also be evident in older adults. In a double-blind, randomized, crossover study, 12 healthy, older (60–70 yr) adults supplemented their diet for 3 days with either nitrate-rich concentrated beetroot juice (BR; 2 × 70 ml/day, ∼9.6 mmol/day NO3−) or a nitrate-depleted beetroot juice placebo (PL; 2 × 70 ml/day, ∼0.01 mmol/day NO3−). Before and after the intervention periods, resting blood pressure and plasma [nitrite] were measured, and subjects completed a battery of physiological and cognitive tests. Nitrate supplementation significantly increased plasma [nitrite] and reduced resting systolic (BR: 115 ± 9 vs. PL: 120 ± 6 mmHg; P < 0.05) and diastolic (BR: 70 ± 5 vs. PL: 73 ± 5 mmHg; P < 0.05) blood pressure. Nitrate supplementation resulted in a speeding of the V̇o2 mean response time (BR: 25 ± 7 vs. PL: 28 ± 7 s; P < 0.05) in the transition from standing rest to treadmill walking, although in contrast to our hypothesis, the O2 cost of exercise remained unchanged. Functional capacity (6-min walk test), the muscle metabolic response to low-intensity exercise, brain metabolite concentrations, and cognitive function were also not altered. Dietary nitrate supplementation reduced resting blood pressure and improved V̇o2 kinetics during treadmill walking in healthy older adults but did not improve walking or cognitive performance. These results may have implications for the enhancement of cardiovascular health in older age.

scholarly journals Dietary nitrate lowers ambulatory blood pressure in treated, uncontrolled hypertension: a 7-d, double-blind, randomised, placebo-controlled, cross-over trial

2018 ◽  
Vol 119 (6) ◽  
pp. 658-663 ◽  
Author(s):  
Conor P. Kerley ◽  
Eamon Dolan ◽  
Philip E. James ◽  
Liam Cormican
Keyword(s):  
Blood Pressure ◽  
Uncontrolled Hypertension ◽  
Beetroot Juice ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Conflicting Evidence ◽  
Before And After ◽  
Plasma Nitrite ◽  
Dietary Strategies ◽  
Existing Data

AbstractDietary nitrate has been shown to increase nitrate/nitrite levels and decrease blood pressure (BP) in multiple populations. There are few reports among hypertensives and these reports have provided conflicting evidence. We aimed to assess the effect of daily nitrate compared with placebo in subjects with uncontrolled hypertension (HTN). On day 0, hypertensives wore an ambulatory BP monitor (ABPM) for 24 h and blood was taken. Subjects were then randomised to 7-d nitrate-rich beetroot juice (NO3−) (12·9 mmol nitrate) followed by 7-d nitrate-depleted beetroot juice (0·5 mmol nitrate) or vice versa. ABPM and blood were assessed before and after both conditions. In all, twenty subjects with treated yet uncontrolled HTN entered and completed the trial (mean age=62·5 years, mean BMI=30·7 kg/m2). Baseline BP was 137/80 (sd7/7) mmHg. Dietary nitrate was well tolerated and resulted in significantly increased plasma nitrite (P=0·0004) and decreased 24-h systolic BP and diastolic BP compared with placebo (−8 mmHg;P=0·012 and −4 mmHg;P=0·018, respectively). Our results support the existing data suggesting an anti-hypertensive effect of dietary nitrate in treated yet uncontrolled hypertensives. Targeted dietary strategies appear promising contributors to BP control.

scholarly journals Effect of Dietary Nitrate Supplementation on Swimming Performance in Trained Swimmers

2017 ◽  
Vol 27 (4) ◽  
pp. 377-384 ◽  
Author(s):  
Sam Lowings ◽  
Oliver Michael Shannon ◽  
Kevin Deighton ◽  
Jamie Matu ◽  
Matthew John Barlow
Keyword(s):  
Nitric Oxide ◽  
Repeated Measures ◽  
Swimming Performance ◽  
Time Trial ◽  
Mean Difference ◽  
Breath Hold ◽  
Double Blind ◽  
Nitric Oxide Concentration ◽  
Nitrate Supplementation ◽  
Maximal Effort

Nitrate supplementation appears to be most ergogenic when oxygen availability is restricted and subsequently may be particularly beneficial for swimming performance due to the breath-hold element of this sport. This represents the first investigation of nitrate supplementation and swimming time-trial (TT) performance. In a randomized double-blind repeated-measures crossover study, ten (5 male, 5 female) trained swimmers ingested 140ml nitrate-rich (~12.5mmol nitrate) or nitrate-depleted (~0.01mmol nitrate) beetroot juice. Three hours later, subjects completed a maximal effort swim TT comprising 168m (8 × 21m lengths) backstroke. Preexercise fractional exhaled nitric oxide concentration was significantly elevated with nitrate compared with placebo, Mean (SD): 17 (9) vs. 7 (3)p.p.b., p = .008. Nitrate supplementation had a likely trivial effect on overall swim TT performance (mean difference 1.22s; 90% CI -0.18–2.6s; 0.93%; p = .144; d = 0.13; unlikely beneficial (22.6%), likely trivial (77.2%), most unlikely negative (0.2%)). The effects of nitrate supplementation during the first half of the TT were trivial (mean difference 0.29s; 90% CI -0.94–1.5s; 0.46%; p = .678; d = 0.05), but there was a possible beneficial effect of nitrate supplementation during the second half of the TT (mean difference 0.93s; 90% CI 0.13–1.70s; 1.36%; p = .062; d = 0.24; possibly beneficial (63.5%), possibly trivial (36.3%), most unlikely negative (0.2%)). The duration and speed of underwater swimming within the performance did not differ between nitrate and placebo (both p > .30). Nitrate supplementation increased nitric oxide bioavailability but did not benefit short-distance swimming performance or the underwater phases of the TT. Further investigation into the effects of nitrate supplementation during the second half of performance tests may be warranted.

scholarly journals Oral nitrate supplementation to enhance pulmonary rehabilitation in COPD: ON-EPIC a multicentre, double-blind, placebo-controlled, randomised parallel group study

Thorax ◽  
2020 ◽  
Vol 75 (7) ◽  
pp. 547-555
Author(s):  
Matthew J Pavitt ◽  
Rebecca Jayne Tanner ◽  
Adam Lewis ◽  
Sara Buttery ◽  
Bhavin Mehta ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Active Treatment ◽  
Treatment Effect ◽  
Pulmonary Rehabilitation ◽  
Activity Level ◽  
Double Blind ◽  
Dietary Nitrate ◽  
Double Blind Placebo ◽  
Parallel Group ◽  
Nitrate Supplementation

RationaleDietary nitrate supplementation has been proposed as a strategy to improve exercise performance, both in healthy individuals and in people with COPD. We aimed to assess whether it could enhance the effect of pulmonary rehabilitation (PR) in COPD.MethodsThis double-blind, placebo-controlled, parallel group, randomised controlled study performed at four UK centres, enrolled adults with Global Initiative for Chronic Obstructive Lung Disease grade II–IV COPD and Medical Research Council dyspnoea score 3–5 or functional limitation to undertake a twice weekly 8-week PR programme. They were randomly assigned (1:1) to either 140 mL of nitrate-rich beetroot juice (BRJ) (12.9 mmol nitrate), or placebo nitrate-deplete BRJ, consumed 3 hours prior to undertaking each PR session. Allocation used computer-generated block randomisation.MeasurementsThe primary outcome was change in incremental shuttle walk test (ISWT) distance. Secondary outcomes included quality of life, physical activity level, endothelial function via flow-mediated dilatation, fat-free mass index and blood pressure parameters.Results165 participants were recruited, 78 randomised to nitrate-rich BRJ and 87 randomised to placebo. Exercise capacity increased more with active treatment (n=57) than placebo (n=65); median (IQR) change in ISWT distance +60 m (10, 85) vs +30 m (0, 70), estimated treatment effect 30 m (95% CI 10 to 40); p=0.027. Active treatment also impacted on systolic blood pressure: treatment group −5.0 mm Hg (−5.0, –3.0) versus control +6.0 mm Hg (−1.0, 15.5), estimated treatment effect −7 mm Hg (95% CI 7 to −20) (p<0.0005). No significant serious adverse events or side effects were reported.ConclusionsDietary nitrate supplementation appears to be a well-tolerated and effective strategy to augment the benefits of PR in COPD.Trial registration numberISRCTN27860457.

Nitrate Supplementation’s Improvement of 10-km Time-Trial Performance in Trained Cyclists

2012 ◽  
Vol 22 (1) ◽  
pp. 64-71 ◽  
Author(s):  
Naomi M. Cermak ◽  
Martin J. Gibala ◽  
Luc J.C. van Loon
Keyword(s):  
Repeated Measures ◽  
Time Trial ◽  
Submaximal Exercise ◽  
Beetroot Juice ◽  
Limited Data ◽  
Double Blind ◽  
Time Trial Performance ◽  
Ergogenic Effects ◽  
Nitrate Supplementation ◽  
Trial Performance

Six days of dietary nitrate supplementation in the form of beetroot juice (~0.5 L/d) has been reported to reduce pulmonary oxygen uptake (VO2) during submaximal exercise and increase tolerance of high-intensity work rates, suggesting that nitrate can be a potent ergogenic aid. Limited data are available regarding the effect of nitrate ingestion on athletic performance, and no study has investigated the potential ergogenic effects of a small-volume, concentrated dose of beetroot juice. The authors tested the hypothesis that 6 d of nitrate ingestion would improve time-trial performance in trained cyclists. Using a double-blind, repeated-measures crossover design, 12 male cyclists (31 ± 3 yr, VO2peak = 58 ± 2 ml · kg−1 · min−1, maximal power [Wmax] = 342 ± 10 W) ingested 140 ml/d of concentrated beetroot (~8 mmol/d nitrate) juice (BEET) or a placebo (nitrate-depleted beetroot juice; PLAC) for 6 d, separated by a 14-d washout. After supplementation on Day 6, subjects performed 60 min of submaximal cycling (2 × 30 min at 45% and 65% Wmax, respectively), followed by a 10-km time trial. Time-trial performance (953 ± 18 vs. 965 ± 18 s, p < .005) and power output (294 ± 12 vs. 288 ± 12 W, p < .05) improved after BEET compared with PLAC supplementation. Submaximal VO2 was lower after BEET (45% Wmax = 1.92 ± 0.06 vs. 2.02 ± 0.09 L/min, 65% Wmax 2.94 ± 0.12 vs. 3.11 ± 0.12 L/min) than with PLAC (main effect, p < .05). Wholebody fuel selection and plasma lactate, glucose, and insulin concentrations did not differ between treatments. Six days of nitrate supplementation reduced VO2 during submaximal exercise and improved time-trial performance in trained cyclists.

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