Solid, Gel, and Liquid Carbohydrate Format Effects on Gut Comfort and Performance

2017 ◽  
Vol 27 (3) ◽  
pp. 247-254 ◽  
Author(s):  
Mathilde Guillochon ◽  
David S. Rowlands
Keyword(s):  
Peak Power ◽  
Perceived Exertion ◽  
Endurance Performance ◽  
Cycling Performance ◽  
Performance Outcomes ◽  
Double Blind ◽  
Fluid Ingestion ◽  
Comparable Performance ◽  
And Performance ◽  
Format Effects

Carbohydrate sports drinks produce worthwhile benefits to endurance performance compared with noncaloric controls. However, athletes now consume carbohydrate in a range of formats, including gels and bars, but the comparable performance outcomes are unknown. Therefore, the aim of this study was to establish the relative effects of drink, gel, bar, and mixed carbohydrate formats on intense cycling performance. In a treatmentapparent randomized crossover design, 12 well-trained male cyclists completed 4 trials comprising a 140-min race simulation, followed by a double-blind slow-ramp to exhaustion (0.333 W·s-1). Carbohydrate comprising fructose and maltodextrin was ingested every 20 min via commercial drink, gel, bar, or mix of all 3, providing 80 g carbohydrate·h-1. Fluid ingestion was 705 ml·h-1. Exertion, fatigue, and gastrointestinal discomfort were measured with VAS. Performance peak power (SD) was 370 (41), 376 (37), 362 (51) and 368 W (54) for drink, gels, bars, and mix respectively. The reduction in power (-3.9%; 90%CI ±4.3) following bar ingestion vs. gel was likely substantial (likelihood harm 81.2%; benefit 0.8%), but no clear differences between drinks, gels, and the mix were evident. Bars also produced small-moderate standardized increases in nausea, stomach fullness, abdominal cramps, and perceived exertion, relative to gels (likelihood harm 95–99.5%; benefit <0.01%) and drink (75–95%; <0.01%); mix also increased nausea relative to gels (95%; <0.01%). Relative to a gel, carbohydrate bar ingestion reduced peak power, gut comfort, and ease of exertion; furthermore, no clear difference relative to drink suggests bars alone are the less favorable exogenous-carbohydrate energy source for intense endurance performance.

scholarly journals Is There an Optimal Ischemic-Preconditioning Dose to Improve Cycling Performance?

2018 ◽  
Vol 13 (3) ◽  
pp. 274-282 ◽  
Author(s):  
Scott Cocking ◽  
Mathew G. Wilson ◽  
David Nichols ◽  
N. Timothy Cable ◽  
Daniel J. Green ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Ischemic Preconditioning ◽  
Perceived Exertion ◽  
Time Trial ◽  
Endurance Performance ◽  
Cycling Performance ◽  
Performance Outcomes ◽  
Rating Of Perceived Exertion ◽  
Cycling Time Trial ◽  
Number Of Cycles

Introduction: Ischemic preconditioning (IPC) may enhance endurance performance. No previous study has directly compared distinct IPC protocols for optimal benefit. Purpose: To determine whether a specific IPC protocol (ie, number of cycles, amount of muscle tissue, and local vs remote occlusion) elicits greater performance outcomes. Methods: Twelve cyclists performed 5 different IPC protocols 30 min before a blinded 375-kJ cycling time trial (TT) in a laboratory. Responses to traditional IPC (4 × 5-min legs) were compared with those to 8 × 5-min legs and sham (dose cycles), 4 × 5-min unilateral legs (dose tissue), and 4 × 5-min arms (remote). Rating of perceived exertion and blood lactate were recorded at each 25% TT completion. Power (W), heart rate (beats/min), and oxygen uptake () (mL · kg−1 · min−1) were measured continuously throughout TTs. Magnitude-based-inference statistics were employed to compare variable differences to the minimal practically important difference. Results: Traditional IPC was associated with a 17-s (0, 34) faster TT time than sham. Applying more dose cycles (8 × 5 min) had no impact on performance. Traditional IPC was associated with likely trivial higher blood lactate and possibly beneficial lower responses vs sham. Unilateral IPC was associated with 18-s (−11, 48) slower performance than bilateral (dose tissue). TT times after remote and local IPC were not different (0 [−16, 16] s). Conclusion: The traditional 4 × 5-min (local or remote) IPC stimulus resulted in the fastest TT time compared with sham; there was no benefit of applying a greater number of cycles or employing unilateral IPC.

Carbohydrate Drink Use During 30 Minutes of Variable-Intensity Exercise Has No Effect on Exercise Performance in Premenarchal Girls

2021 ◽  
Vol 33 (2) ◽  
pp. 65-69
Author(s):  
C. Eric Heidorn ◽  
Brandon J. Dykstra ◽  
Cori A. Conner ◽  
Anthony D. Mahon
Keyword(s):  
Peak Power ◽  
Perceived Exertion ◽  
Rating Of Perceived Exertion ◽  
Fatigue Index ◽  
Mean Power ◽  
Variable Intensity ◽  
Performance Effects ◽  
Power Peak ◽  
The Mean ◽  
And Performance

Purpose: This study examined the physiological, perceptual, and performance effects of a 6% carbohydrate (CHO) drink during variable-intensity exercise (VIE) and a postexercise test in premenarchal girls. Methods: A total of 10 girls (10.4 [0.7] y) participated in the study. VO2peak was assessed, and the girls were familiarized with VIE and performance during the first visit. The trial order (CHO and placebo) was randomly assigned for subsequent visits. The drinks were given before VIE bouts and 1-minute performance (9 mL/kg total). Two 15-minute bouts of VIE were completed (10 repeated sequences of 20%, 55%, and 95% power at VO2peak and maximal sprints) before a 1-minute performance sprint. Results: The mean power, peak power, heart rate (HR), %HRpeak, and rating of perceived exertion during VIE did not differ between trials. However, the peak power decreased, and the rating of perceived exertion increased from the first to the second bout. During the 1-minute performance, there were no differences between the trial (CHO vs placebo) for HR (190 [9] vs 189 [9] bpm), %HRpeak (97.0% [3.2%] vs 96.6% [3.0%]), rating of perceived exertion (7.8 [2.3] vs 8.1 [1.9]), peak power (238 [70] vs 235 [60] W), fatigue index (54.7% [10.0%] vs 55.9% [12.8%]), or total work (9.4 [2.6] vs 9.4 [2.1] kJ). Conclusion: CHO supplementation did not alter physiological, perceptual, or performance responses during 30 minutes of VIE or postexercise sprint performance in premenarchal girls.

Dietary Antioxidant Supplementation Combined with Quercetin Improves Cycling Time Trial Performance

2006 ◽  
Vol 16 (4) ◽  
pp. 405-419 ◽  
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.

Increased Cardiorespiratory Stress During Submaximal Cycling After Ketone Monoester Ingestion in Endurance-Trained Adults

2021 ◽  
Author(s):  
Devin Goddard McCarthy ◽  
William Bostad ◽  
Fiona Jane Powley ◽  
Jonathan P. Little ◽  
Douglas Richards ◽  
...  
Keyword(s):  
Body Mass ◽  
Ketone Body ◽  
Perceived Exertion ◽  
Bolus Dose ◽  
Ventilatory Threshold ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Threshold Intensity ◽  
Double Blind ◽  
And Performance

There is growing interest in the effect of exogenous ketone body supplementation on exercise responses and performance. The limited studies to date have yielded equivocal data, likely due in part to differences in dosing strategy, increase in blood ketones, and participant training status. Using a randomized, double-blind, counterbalanced design, we examined the effect of ingesting a ketone monoester (KE) supplement (600 mg/kg body mass) or flavour-matched placebo in endurance-trained adults (n=10 males, n=9 females; VO2peak=57±8 ml/kg/min). Participants performed a 30-min cycling bout at ventilatory threshold intensity (71±3% VO2peak), followed 15 min later by a 3 kJ/kg body mass time-trial. KE versus placebo ingestion increased plasma [β-hydroxybutyrate] before exercise (3.9±1.0 vs 0.2±0.3 mM, p<0.0001, dz=3.4), ventilation (77±17 vs 71±15 L/min, p<0.0001, dz=1.3) and heart rate (155±11 vs 150±11 beats/min, p<0.001, dz=1.2) during exercise, and rating of perceived exertion at the end of exercise (15.4±1.6 vs 14.5±1.2, p<0.01, dz=0.85). Plasma [β-hydroxybutyrate] remained higher after KE vs placebo ingestion before the time-trial (3.5±1.0 vs 0.3±0.2 mM, p<0.0001, dz=3.1), but performance was not different (KE: 16:25±2:50 vs placebo: 16:06±2:40 min:s, p=0.20; dz=0.31). We conclude that acute ingestion of a relatively large KE bolus dose increased markers of cardiorespiratory stress during submaximal exercise in endurance-trained participants. Novelty bullets: •Limited studies have yielded equivocal data regarding exercise responses after acute ketone body supplementation. •Using a randomized, double-blind, placebo-controlled, counterbalanced design, we found that ingestion of a large bolus dose of a commercial ketone monoester supplement increased markers of cardiorespiratory stress during cycling at ventilatory threshold intensity in endurance-trained adults.

scholarly journals Effects of Pre-Exercise High and Low Glycaemic Meal on Intermittent Sprint and Endurance Exercise Performance

Sports ◽  
2019 ◽  
Vol 7 (8) ◽  
pp. 188 ◽  
Author(s):  
Man Tong Chua ◽  
Govindasamy Balasekaran ◽  
Mohammed Ihsan ◽  
Abdul Rashid Aziz
Keyword(s):  
Endurance Exercise ◽  
Exercise Performance ◽  
Perceived Exertion ◽  
Endurance Performance ◽  
Random Order ◽  
Glycaemic Index ◽  
Performance Outcomes ◽  
Exercise Heart Rate ◽  
Significant Difference ◽  
Varsity Athletes

The purpose of this study is to investigate the effects of ingesting either a high glycaemic index (HGI) or low glycaemic index (LGI) carbohydrate meal (preceding a 12 h overnight fast and where the meal was ingested 45-min prior to activity) on intermittent sprint and endurance exercise performance. Ten male varsity athletes from intermittent sports (age 23.6 ± 1.7 years, VO2max 51.9 ± 4.7 mL·kg−1·min−1) underwent a peak velocity (Vpeak) test and familiarisation session, followed by two experimental sessions in random order. Experimental sessions involved the ingestion of either an HGI or LGI meal, followed by the completion of the modified Loughborough Intermittent Shuttle Test (mLIST). There was no significant difference between HGI or LGI meals on sprint times (p = 0.62) and distance to exhaustion (p = 0.54) in the mLIST. Exercise heart rate, blood lactate and ratings of perceived exertion were also similar between the two meal trials throughout the mLIST (all p > 0.05). Subjective ratings of hunger, fullness, satiety and satisfaction were also not significantly different between the two meals. In conclusion, consuming either an HGI or LGI meal after a prolonged 12 h fast and ingesting the meal 45 min prior to exercise did not differ in either physiological, subjective and intermittent sprint and endurance performance outcomes.

scholarly journals The Physiological Effects of Amino Acids Arginine and Citrulline: Is There a Basis for Development of a Beverage to Promote Endurance Performance? A Narrative Review of Orally Administered Supplements

Beverages ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 11 ◽  
Author(s):  
Hollie Speer ◽  
Nathan M. D’Cunha ◽  
Michael J. Davies ◽  
Andrew J. McKune ◽  
Nenad Naumovski
Keyword(s):  
Synergistic Effects ◽  
Endurance Performance ◽  
Performance Outcomes ◽  
Time To Exhaustion ◽  
No Production ◽  
Full Potential ◽  
Physiological Effects ◽  
And Performance ◽  
Physiological Benefits ◽  
Endothelial Nitric Oxide

Nutritional and ergogenic aid supplementation is prevalent within athletic or general fitness populations, and is only continuing to gain momentum. Taken in isolation or as a combination, amino acid (AA) supplementation has the potential to increase endurance performance among other benefits. L-Arginine (L-Arg) and L-Citrulline (L-Cit) are two AAs proposed to increase endothelial nitric oxide (NO) synthesis, with potential additional physiological benefits, and therefore may contribute to enhanced performance outcomes such as increased power output, or time to exhaustion. However, the appropriate dose for promoting physiological and performance benefits of these AAs, and their potential synergistic effects remains to be determined. Therefore, the aim of this review was to evaluate the varied concentrations used in the current literature, assess the effects of L-Arg and L-Cit in combination on physiological responses and endurance performance, and consider if there is a fundamental basis for providing these supplements in the form of a beverage. A total of six studies were considered eligible for the review which utilized a range of 3–8 g of the AA constituents. The findings support the notion that supplementing with a combination of L-Arg and L-Cit may increase NO production, enhance vasodilation, and therefore increase performance capacity in athletes. A beverage as a carrier for the two AAs is worth considering; however, there remains limited research assessing these outcomes across a consistent range of concentrations in order to see their full potential.

Composite versus single transportable carbohydrate solution enhances race and laboratory cycling performance

2012 ◽  
Vol 37 (3) ◽  
pp. 425-436 ◽  
Author(s):  
David S. Rowlands ◽  
Marilla Swift ◽  
Marjolein Ros ◽  
Jackson G. Green
Keyword(s):  
High Intensity ◽  
Peak Power ◽  
Endurance Performance ◽  
Cycling Performance ◽  
Mountain Bike ◽  
Gastrointestinal Discomfort ◽  
Recorded Data ◽  
Intestinal Transporters ◽  
Maltodextrin Solution ◽  
Carbohydrate Solution

When ingested at high rates (1.8–2.4 g·min–1) in concentrated solutions, carbohydrates absorbed by multiple (e.g., fructose and glucose) vs. single intestinal transporters can increase exogenous carbohydrate oxidation and endurance performance, but their effect when ingested at lower, more realistic, rates during intermittent high-intensity endurance competition and trials is unknown. Trained cyclists participated in two independent randomized crossover investigations comprising mountain-bike races (average 141 min; n = 10) and laboratory trials (94-min high-intensity intervals followed by 10 maximal sprints; n = 16). Solutions ingested during exercise contained electrolytes and fructose + maltodextrin or glucose + maltodextrin in 1:2 ratio ingested, on average, at 1.2 g carbohydrate·kg–1·h–1. Exertion, muscle fatigue, and gastrointestinal discomfort were recorded. Data were analysed using mixed models with gastrointestinal discomfort as a mechanism covariate; inferences were made against substantiveness thresholds (1.2% for performance) and standardized difference. The fructose–maltodextrin solution substantially reduced race time (–1.8%; 90% confidence interval = ±1.8%) and abdominal cramps (–8.1 on a 0–100 scale; ±6.6). After accounting for gastrointestinal discomfort, the effect of the fructose–maltodextrin solution on lap time was reduced (–1.1%; ±2.4%), suggesting that gastrointestinal discomfort explained part of the effect of fructose–maltodextrin on performance. In the laboratory, mean sprint power was enhanced (1.4%; ±0.8%) with fructose–maltodextrin, but the effect on peak power was unclear (0.7%; ±1.5%). Adjusting out gastrointestinal discomfort augmented the fructose–maltodextrin effect on mean (2.6%; ±1.9%) and peak (2.5%; ±3.0%) power. Ingestion of multiple transportable vs. single transportable carbohydrates enhanced mountain-bike race and high-intensity laboratory cycling performance, with inconsistent but not irreconcilable effects of gut discomfort as a possible mediating mechanism.

Caffeine effects on VO2max test outcomes investigated by a placebo perceived-as-caffeine design

2017 ◽  
Vol 23 (4) ◽  
pp. 231-238 ◽  
Author(s):  
Cayque Brietzke ◽  
Ricardo Yukio Asano ◽  
Felipe De Russi de Lima ◽  
Fabiano Aparecido Pinheiro ◽  
Franco-Alvarenga ◽  
...  
Keyword(s):  
Power Output ◽  
Peak Power ◽  
Perceived Exertion ◽  
Performance Outcomes ◽  
Peak Power Output ◽  
Time To Exhaustion ◽  
Ratings Of Perceived Exertion ◽  
Ergogenic Effects ◽  
Vo2max Test ◽  
Test Outcomes

Background: Ergogenic effects of caffeine (CAF) ingestion have been observed in different cycling exercise modes, and have been associated with alterations in ratings of perceived exertion (RPE). However, there has been little investigation of maximal oxygen uptake (VO2MAX) test outcomes. Aim: This study aimed to verify whether CAF may reduce RPE, thereby improving maximal incremental test (MIT) outcomes such as VO2MAX, time to exhaustion and peak power output (WPEAK). Methods: Nine healthy individuals performed three MITs (25 W/min until exhaustion) in a random, counterbalanced fashion after ingestion of CAF, placebo perceived as caffeine (PLA), and no supplementation (baseline control). VO2 was measured throughout the test, while RPE was rated according to overall and leg effort sensations. The power output corresponding to submaximal (RPE = 14 according to the 6–20 Borg scale) and maximal RPE was recorded for both overall (O-RPE14 and O-RPEMAX) and leg RPE (L-RPE14 and L-RPEMAX). Results: VO2MAX did not change significantly between MITs; however, CAF and PLA increased time to exhaustion (↑ ∼18.7% and ∼17.1%, respectively; p < .05) and WPEAK (↑ ∼13.0% and ∼11.8%, respectively; p < .05) when compared with control. When compared with control, CAF ingestion reduced submaximal and maximal overall and leg RPEs, the effect being greater in maximal (likely beneficial in O-RPEMAX and L-RPEMAX) than submaximal RPE (possibly beneficial in O-RPE14 and L-RPE14). Similar results were found when participants ingested PLA. Conclusions: Compared with control, CAF and PLA improved MIT performance outcomes such as time to exhaustion and WPEAK, without altering VO2MAX values. CAF effects were attributed to placebo.

Precision, Accuracy, and Performance Outcomes of Perceived Exertion vs. Heart Rate Guided Run-training

2017 ◽  
Vol 31 (3) ◽  
pp. 630-637
Author(s):  
Evan C. Johnson ◽  
Riana R. Pryor ◽  
Douglas J. Casa ◽  
Lindsay A. Ellis ◽  
Carl M. Maresh ◽  
...  
Keyword(s):  
Heart Rate ◽  
Perceived Exertion ◽  
Performance Outcomes ◽  
And Performance

The Effects of Choline Supplementation on Physical Performance

2000 ◽  
Vol 10 (2) ◽  
pp. 170-181 ◽  
Author(s):  
John P. Warber ◽  
John F. Patton ◽  
William J. Tharion ◽  
Steven H. Zeisel ◽  
Robert P. Mello ◽  
...  
Keyword(s):  
Physical Performance ◽  
Perceived Exertion ◽  
Performance Measure ◽  
Load Carriage ◽  
Strenuous Exercise ◽  
Time To Exhaustion ◽  
Double Blind ◽  
Total Load ◽  
And Performance ◽  
Heavy Loads

It has been reported that plasma choline levels decrease following certain types of strenuous exercise. Preliminary findings also suggest that a drop in plasma choline may limit physical performance, while choline supplementation may delay fatigue during prolonged efforts. A double-blind crossover design was used to determine the relationship between plasma choline and performance during and after 4 hr of strenuous exercise. Volunteers (N = 14) received either a placebo or treatment beverage (8.425 g choline citrate) prior to and midway through a 4-hr load carriage treadmill exercise (3% grade at 5.6 km/h × 20 km) carrying a total load of 34.1 kg. Following the treadmill test, run time-to-exhaustion and squat tests were performed, and perceived exertion, plasma choline, glycerophosphocholine, and phosphatidylcholine were measured. Plasma choline levels increased 128% after the run-to-exhaustion with the choline supplemented beverage but remained unchanged with the placebo beverage. No significant effects were seen with choline supplementation on any outcome performance measure. Consequently, soldiers conditioned to carry heavy loads over long distances do not deplete plasma choline as a result of a prolonged exhaustive exercise under a placebo beverage, nor do they benefit from choline supplementation to delay fatigue under the same conditions.

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