The Effect of Nitrate Supplementation on Cycling Performance in the Heat in Well-Trained Cyclists

Purpose: To determine the effect of consumption on measures of perception, thermoregulation, and cycling performance in hot conditions. Methods: In a randomized, double-blind, crossover design, 8 well-trained cyclists (mean ± SD age 25 ± 8 y, peak 64 ± 5 mL · kg−1 · min−1) performed 2 separate trials in hot (35°C, 60% relative humidity) environments, having ingested either 140 mL -rich beetroot juice ∼8 mmol (NIT) or placebo (PLA) daily for 3 d with a 7-d washout period separating trials. Trials consisted of 2 × 10-min bouts at 40% and 60% peak power output (PPO) to determine physiological and perceptual responses to the heat, followed by a 4-km cycling time trial. Results: Basal [nitrite] was substantially elevated in NIT (2.70 ± 0.98 µM) vs PLA (1.10 ± 0.61 µM), resulting in a most likely (ES = 1.58 ± 0.93) increase after 3 d. There was a very likely trivial increase in rectal temperature in NIT at 40% (PLA 37.4°C ± 0.2°C vs NIT 37.5°C ± 0.3°C, 0.1°C ± 0.2°C) and 60% (PLA 37.8°C ± 0.2°C vs NIT 37.9°C ± 0.3°C, 0.1°C ± 0.2°C) PPO. Cycling performance was similar between trials (PLA 336 ± 45 W vs NIT 337 ± 50 W, CV ± 95%CL; 0.2% ± 2.5%). Outcomes for heart rate and perceptual measures were unclear across the majority of time points. Conclusions: Three days of supplementation resulted in small increases in rectal temperature during low- to moderate-intensity exercise, but this did not appear to influence 4-km cycling time-trial performance in hot climates.

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Single and combined effects of beetroot juice and caffeine supplementation on cycling time trial performance

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2013-0336 ◽

2014 ◽

Vol 39 (9) ◽

pp. 1050-1057 ◽

Cited By ~ 58

Author(s):

Stephen C. Lane ◽

John A. Hawley ◽

Ben Desbrow ◽

Andrew M. Jones ◽

James R. Blackwell ◽

...

Keyword(s):

Best Practice ◽

Latin Square ◽

Time Trial ◽

Cycling Performance ◽

Cycle Ergometer ◽

Beetroot Juice ◽

Double Blind ◽

Cycling Time Trial ◽

Competitive Cyclists ◽

Cycling Time

Both caffeine and beetroot juice have ergogenic effects on endurance cycling performance. We investigated whether there is an additive effect of these supplements on the performance of a cycling time trial (TT) simulating the 2012 London Olympic Games course. Twelve male and 12 female competitive cyclists each completed 4 experimental trials in a double-blind Latin square design. Trials were undertaken with a caffeinated gum (CAFF) (3 mg·kg−1 body mass (BM), 40 min prior to the TT), concentrated beetroot juice supplementation (BJ) (8.4 mmol of nitrate (NO3–), 2 h prior to the TT), caffeine plus beetroot juice (CAFF+BJ), or a control (CONT). Subjects completed the TT (females: 29.35 km; males: 43.83 km) on a laboratory cycle ergometer under conditions of best practice nutrition: following a carbohydrate-rich pre-event meal, with the ingestion of a carbohydrate–electrolyte drink and regular oral carbohydrate contact during the TT. Compared with CONT, power output was significantly enhanced after CAFF+BJ and CAFF (3.0% and 3.9%, respectively, p < 0.01). There was no effect of BJ supplementation when used alone (–0.4%, p = 0.6 compared with CONT) or when combined with caffeine (–0.9%, p = 0.4 compared with CAFF). We conclude that caffeine (3 mg·kg−1 BM) administered in the form of a caffeinated gum increased cycling TT performance lasting ∼50–60 min by ∼3%–4% in both males and females. Beetroot juice supplementation was not ergogenic under the conditions of this study.

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Dietary Nitrate Fails to Improve 1 and 4 km Cycling Performance in Highly Trained Cyclists

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2016-0212 ◽

2017 ◽

Vol 27 (3) ◽

pp. 255-263 ◽

Cited By ~ 18

Author(s):

Joseph A. McQuillan ◽

Deborah K. Dulson ◽

Paul B. Laursen ◽

Andrew E. Kilding

Keyword(s):

Time Trial ◽

Cycling Performance ◽

Peak Power Output ◽

Placebo Effects ◽

Mean Power ◽

Double Blind ◽

Dietary Nitrate ◽

Time Trial Performance ◽

Cycling Time ◽

Trial Performance

We aimed to compare the effects of two different dosing durations of dietary nitrate (NO3-) supplementation on 1 and 4 km cycling time-trial performance in highly trained cyclists. In a double-blind crossover-design, nine highly trained cyclists ingested 140ml of NO3--rich beetroot juice containing ~8.0mmol [NO3-], or placebo, for seven days. Participants completed a range of laboratory-based trials to quantify physiological and perceptual responses and cycling performance: time-trials on day 3 and 6 (4km) and on day 4 and 7 (1km) of the supplementation period. Relative to placebo, effects following 3- and 4-days of NO3- supplementation were unclear for 4 (-0.8; 95% CL, ± 2.8%, p = .54) and likely harmful for 1km (-1.9; ± 2.5% CL, p = .17) time-trial mean power. Effects following 6- and 7-days of NO3- supplementation resulted in unclear effects for 4 (0.1; ± 2.2% CL, p = .93) and 1km (-0.9; ± 2.6%CL, p = .51) time-trial mean power. Relative to placebo, effects for 40, 50, and 60% peak power output were unclear for economy at days 3 and 6 of NO3- supplementation (p > .05). Dietary NO3- supplementation appears to be detrimental to 1km time-trial performance in highly trained cyclists after 4-days. While, extending NO3- dosing to ≥ 6-days reduced the magnitude of harm in both distances, overall performance in short duration cycling time-trials did not improve relative to placebo.

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Does caffeine supplementation alter energy contribution during a work-based ~30 min cycling time-trial?

Revista Brasileira de Educação Física e Esporte ◽

10.11606/issn.1981-4690.v34i3p471-481 ◽

2020 ◽

Vol 34 (3) ◽

pp. 471-481

Author(s):

Gabriel Barreto ◽

Rafael Pires da Silva ◽

Guilherme Yamaguchi ◽

Luana Farias de Oliveira ◽

Vitor de Salles Painelli ◽

...

Keyword(s):

Perceived Exertion ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

Time Trial ◽

Energy System ◽

Energy Contribution ◽

Mean Power ◽

Double Blind ◽

Cycling Time Trial ◽

Cycling Time

Caffeine has been shown to increase anaerobic energy contribution during short-duration cycling time-trials (TT) though no information exists on whether caffeine alters energy contribution during more prolonged, aerobic type TTs. The aim of this study was to determine the effects of caffeine supplementation on longer and predominantly aerobic exercise. Fifteen recreationally-trained male cyclists (age 38±8 y, height 1.76±0.07 m, body mass 72.9±7.7 kg) performed a ~30 min cycling TT following either 6 mg·kg-1BM caffeine (CAF) or placebo (PLA) supplementation, and one control (CON) session without supplementation, in a double- -blind, randomised, counterbalance and cross-over design. Mean power output (MPO) was recorded as the outcome measure. Respiratory values were measured throughout exercise for the determination of energy system contribution. Data were analysed using mixed-models. CAF improved mean MPO compared to CON (P=0.01), and a trend towards an improvement compared to PLA (P=0.07); there was no difference in MPO at any timepoint throughout the exercise between conditions. There was a main effect of Condition (P=0.04) and Time (P<0.0001) on blood lactate concentration, which tended to be higher in CAF vs. both PLA and CON (Condition effect, both P=0.07). Ratings of perceived exertion increased over time (P<0.0001), with no effect of Condition or interaction (both P>0.05). Glycolytic energy contribution was increased in CAF compared to CON and PLA (both P<0.05), but not aerobic or ATP-CP (both P>0.05). CAF improved aerobic TT performance compared to CON, which could be explained by increased glycolytic energy contribution.

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

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2016-0202 ◽

2017 ◽

Vol 12 (5) ◽

pp. 684-689 ◽

Cited By ~ 9

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.

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Dietary Antioxidant Supplementation Combined with Quercetin Improves Cycling Time Trial Performance

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.16.4.405 ◽

2006 ◽

Vol 16 (4) ◽

pp. 405-419 ◽

Cited By ~ 68

Author(s):

Holden S-H. MacRae ◽

Kari M. Mefferd

Keyword(s):

Peak Power ◽

Time Trial ◽

Cycling Performance ◽

Antioxidant Supplementation ◽

Double Blind ◽

Cycling Time Trial ◽

Dietary Antioxidant ◽

Power Peak ◽

Manova Analysis ◽

Trial Performance

We investigated whether 6 wk of antioxidant supplementation (AS) would enhance 30 km time trial (TT) cycling performance. Eleven elite male cyclists completed a randomized, double-blind, cross-over study to test the effects of twice daily AS containing essential vitamins plus quercetin (FRS), and AS minus quercetin (FRS-Q) versus a baseline TT (B). MANOVA analysis showed that time to complete the 30 km TT was improved by 3.1% on FRS compared to B (P ≤ 0.01), and by 2% over the last 5 km (P ≤ 0.05). Absolute and relative (%HRmax) heart rates and percent VO2max were not different between trials, but average and relative power (% peak power) was higher on FRS (P ≤ 0.01). Rates of carbohydrate and fat oxidation were not different between trials. Thus, FRS supplementation significantly improved high-intensity cycling TT performance through enhancement of power output. Further study is needed to determine the potential mechanism(s) of the antioxidant efficacy.

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Cycling Time Trial Performance 4 Hours After Glycogen-Lowering Exercise Is Similarly Enhanced by Recovery Nondairy Chocolate Beverages Versus Chocolate Milk

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2015-0056 ◽

2016 ◽

Vol 26 (1) ◽

pp. 65-70 ◽

Cited By ~ 9

Author(s):

Adam U. Upshaw ◽

Tiffany S. Wong ◽

Arash Bandegan ◽

Peter W.R. Lemon

Keyword(s):

Repeated Measures ◽

Time Trial ◽

Chocolate Milk ◽

Double Blind ◽

Time Trial Performance ◽

Cycling Time Trial ◽

Repeated Measures Design ◽

Dairy Milk ◽

Cycling Time ◽

Trial Performance

Postexercise chocolate milk ingestion has been shown to enhance both glycogen resynthesis and subsequent exercise performance. To assess whether nondairy chocolate beverage ingestion post–glycogen-lowering exercise can enhance 20-km cycling time trial performance 4 hr later, eight healthy trained male cyclists (21.8 ± 2.3y, VO2max = 61.2 ± 1.4 ml·kg-1·min-1; M ± SD) completed a series of intense cycling intervals designed to lower muscle glycogen (Jentjens & Jeukendrup, 2003) followed by 4 hr of recovery and a subsequent 20-km cycling time trial. During the first 2 hr of recovery, participants ingested chocolate dairy milk (DAIRYCHOC), chocolate soy beverage (SOYCHOC), chocolate hemp beverage (HEMPCHOC), low-fat dairy milk (MILK), or a low-energy artificially sweetened, flavored beverage (PLACEBO) at 30-min intervals in a double-blind, counterbalanced repeated-measures design. All drinks, except the PLACEBO (247 kJ) were isoenergetic (2,107 kJ), and all chocolate-flavored drinks provided 1-g CHO·kg body mass-1·h-1. Fluid intake across treatments was equalized (2,262 ± 148 ml) by ingesting appropriate quantities of water based on drink intake. The CHO:PRO ratio was 4:1, 1.5:1, 4:1, and 6:1 for DAIRYCHOC, MILK, SOYCHOC, and HEMPCHOC, respectively. One-way analysis of variance with repeated measures showed time trial performance (DAIRYCHOC = 34.58 ± 2.5 min, SOYCHOC = 34.83 ± 2.2 min, HEMPCHOC = 34.88 ± 1.1 min, MILK = 34.47 ± 1.7 min) was enhanced similarly vs PLACEBO (37.85 ± 2.1) for all treatments (p = .019) These data suggest that postexercise macronutrient and total energy intake are more important for same-day 20-km cycling time trial performance after glycogen-lowering exercise than protein type or protein-to-carbohydrate ratio.

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Influence of 2-Weeks Ingestion of High Chlorogenic Acid Coffee on Mood State, Performance, and Postexercise Inflammation and Oxidative Stress: A Randomized, Placebo-Controlled Trial

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2017-0198 ◽

2018 ◽

Vol 28 (1) ◽

pp. 55-65 ◽

Cited By ~ 5

Author(s):

David C. Nieman ◽

Courtney L. Goodman ◽

Christopher R. Capps ◽

Zack L. Shue ◽

Robert Arnot

Keyword(s):

Oxidative Stress ◽

Chlorogenic Acid ◽

Mood State ◽

Controlled Trial ◽

Time Trial ◽

Cycling Performance ◽

Cycling Time Trial ◽

Reducing Ability ◽

And Oxidative Stress ◽

Cycling Time

This study measured the influence of 2-weeks ingestion of high chlorogenic acid (CQA) coffee on postexercise inflammation and oxidative stress, with secondary outcomes including performance and mood state. Cyclists (N = 15) were randomized to CQA coffee or placebo (300 ml/day) for 2 weeks, participated in a 50-km cycling time trial, and then crossed over to the opposite condition with a 2-week washout period. Blood samples were collected pre- and postsupplementation, and immediately postexercise. CQA coffee was prepared using the Turkish method with 30 g lightly roasted, highly ground Hambela coffee beans in 300 ml boiling water, and provided 1,066 mg CQA and 474 mg caffeine versus 187 mg CQA and 33 mg caffeine for placebo. Plasma caffeine was higher with CQA coffee versus placebo after 2-weeks (3.3-fold) and postexercise (21.0-fold) (interaction effect, p < .001). Higher ferric reducing ability of plasma (FRAP) levels were measured after exercise with CQA coffee versus placebo (p = .01). No differences between CQA coffee and placebo were found for postexercise increases in plasma IL-6 (p = .74) and hydroxyoctadecadienoic acids (9 + 13 HODEs) (p = .99). Total mood disturbance (TMD) scores were lower with CQA coffee versus placebo (p = .04). 50-km cycling time performance and power did not differ between trials, with heart rate and ventilation higher with CQA coffee, especially after 30 min. In summary, despite more favorable TMD scores with CQA coffee, these data do not support the chronic use of coffee highly concentrated with chlorogenic acids and caffeine in mitigating postexercise inflammation or oxidative stress or improving 50-km cycling performance.

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Reliability of Physiological Attributes and Their Association With Stochastic Cycling Performance

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2013-0048 ◽

2014 ◽

Vol 9 (2) ◽

pp. 309-315 ◽

Cited By ~ 2

Author(s):

Gregory T. Levin ◽

Paul B. Laursen ◽

Chris R. Abbiss

Keyword(s):

Power Output ◽

Ventilatory Threshold ◽

Intraclass Correlation ◽

Time Trial ◽

Cycling Performance ◽

Peak Power Output ◽

Cycling Time Trial ◽

Physiological Variables ◽

Physiological Attributes ◽

And Performance

Purpose:To assess the reliability of a 5-min-stage graded exercise test (GXT) and determine the association between physiological attributes and performance over stochastic cycling trials of varying distance.Methods:Twenty-eight well-trained male cyclists performed 2 GXTs and either a 30-km (n = 17) or a 100-km stochastic cycling time trial (n = 9). Stochastic cycling trials included periods of high-intensity efforts for durations of 250 m, 1 km, or 4 km depending on the test being performing.Results:Maximal physiological attributes were found to be extremely reliable (maximal oxygen uptake [VO2max]: coefficient of variation [CV] 3.0%, intraclass correlation coefficient [ICC] .911; peak power output [PPO]: CV 3.0%, ICC .913), but a greater variability was found in ventilatory thresholds and economy. All physiological variables measured during the GXT, except economy at 200 W, were correlated with 30-km cycling performance. Power output during the 250-m and 1-km efforts of the 30-km trial were correlated with VO2max, PPO, and the power output at the second ventilatory threshold (r = .58–.82). PPO was the only physiological attributed measured during the GXT to be correlated with performance during the 100-km cycling trial (r = .64).Conclusions:Many physiological variables from a reliable GXT were associated with performance over shorter (30-km) but not longer (100-km) stochastic cycling trials.

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Sex-Specific Effects of Respiratory Muscle Endurance Training on Cycling Time Trial Performance in Normoxia and Hypoxia

Frontiers in Physiology ◽

10.3389/fphys.2021.700620 ◽

2021 ◽

Vol 12 ◽

Author(s):

Julie Chambault ◽

Grégorine Grand ◽

Bengt Kayser

Keyword(s):

Heart Rate ◽

Endurance Training ◽

Respiratory System ◽

Respiratory Muscle ◽

Time Trial ◽

Cycling Performance ◽

Muscle Endurance ◽

Cycling Time Trial ◽

Respiratory Muscle Endurance ◽

Cycling Time

Objectives: We tested the hypotheses that respiratory muscle endurance training (RMET) improves endurance cycling performance differently in women and men and more so in hypoxia than in normoxia.Design: A prospective pre–post cross-over study with two testing conditions.Methods: Healthy and active women (seven, 24 ± 4 years, mean ± standard deviation [SD]) and men (seven, 27 ± 5 years) performed incremental cycling to determine maximum oxygen consumption (VO2peak) and power output (Wpeak) and on different days two 10-km cycling time trials (TTs) in normoxia and normobaric hypoxia (FiO2, 0.135, ~3,500 m equivalent), in a balanced randomized order. Next they performed supervised RMET in normoxia (4 weeks, 5 days/week, 30 min/day eucapnic hyperpnea at ~60% predicted maximum voluntary ventilation) followed by identical post-tests. During TTs, heart rate, ear oximetry reading, and Wpeak were recorded.Results: The VO2peak and Wpeak values were unchanged after RMET. The TT was improved by 7 ± 6% (p < 0.001) in normoxia and 16 ± 6% (p < 0.001) in hypoxia. The difference between normoxic and hypoxic TT was smaller after RMET as compared with that before RMET (14% vs. 21%, respectively, p < 0.001). All effects were greater in women (p < 0.001). The RMET did not change the heart rate or ear oximetry reading during TTs.Conclusion: We found a greater effect of RMET on cycling TT performance in women than in men, an effect more pronounced in hypoxia. These findings are congruent with the contention of a more pronounced performance-limiting role of the respiratory system during endurance exercise in hypoxia compared with normoxia and more so in women whose respiratory system is undersized compared with that of men.

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