scholarly journals Acute Caffeine and Coconut Oil Intake, Isolated or Combined, Does Not Improve Running Times of Recreational Runners: A Randomized, Placebo-Controlled and Crossover Study

Nutrients ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1661
Author(s):  
Gabrielle de Lima Borba ◽  
Julianne Soares de Freitas Batista ◽  
Ludmilla Marques Queiroz Novais ◽  
Myrnzzia Beatriz Silva ◽  
João Batista da Silva Júnior ◽  
...  
Keyword(s):  
Crossover Study ◽  
Perceived Exertion ◽  
Coconut Oil ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Soy Oil ◽  
Borg Scale ◽  
Virgin Coconut Oil ◽  
Decaffeinated Coffee ◽  
Recreational Runners

The aim was to evaluate the effect of caffeine (CAF) and extra virgin coconut oil (CO), isolated or combined, on running performance in runners. Methods: A randomized, placebo-controlled, and crossover study was conducted with thirteen recreational runners aged 18–40. All volunteers performed a 1600 m time trial at a 400 m track, each ingesting four different substances: (1) placebo (water), (2) decaffeinated coffee plus isolated CAF (DECAF + CAF), (3) decaffeinated coffee plus isolated CAF plus soy oil (DECAF + CAF + SO), and (4) decaffeinated coffee plus isolated CAF plus extra virgin coconut oil (DECAF + CAF + CO). The substances were ingested 60 min before the trials, the order of the situations was randomized, and there were one-week intervals between them. At the end of the trials, the Borg scale was applied to evaluate the rating of perceived exertion (RPE) and the time was measured. Results: Our data did not show differences in running time among the trials (placebo: 7.64 ± 0.80, DECAF + CAF: 7.61 ± 1.02, DECAF + CAF + SO: 7.66 ± 0.89, and DECAF + CAF + CO: 7.58 ± 0.74 min; p = 0.93), nor RPE (placebo: 6.15 ± 2.03, DECAF + CAF: 6.00 ± 2.27, DECAF + CAF + SO: 6.54 ± 2.73, and DECAF + CAF + CO: 6.00 ± 2.45 score; p = 0.99). Lactate concentrations (placebo: 6.23 ± 2.72, DECAF + CAF: 4.43 ± 3.77, DECAF + CAF + SO: 5.29 ± 3.77, and DECAF + CAF + CO: 6.17 ± 4.18 mmol/L; p = 0.55) also was not modified. Conclusion: Our study shows that ingestion of decaffeinated coffee with the addition of isolated CAF and extra virgin CO, either isolated or combined, does not improve 1600 m running times, nor influence RPE and lactate concentrations in recreational runners. Thus, combination of coffee with CO as a pre-workout supplement seems to be unsubstantiated for a short-distance race.

scholarly journals Protection Against Spikes in Workload With Aerobic Fitness and Playing Experience: The Role of the Acute:Chronic Workload Ratio on Injury Risk in Elite Gaelic Football

2017 ◽  
Vol 12 (3) ◽  
pp. 393-401 ◽  
Author(s):  
Shane Malone ◽  
Mark Roe ◽  
Dominic A. Doran ◽  
Tim J. Gabbett ◽  
Kieran D. Collins
Keyword(s):  
Aerobic Fitness ◽  
Injury Risk ◽  
Perceived Exertion ◽  
Reference Group ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Football Players ◽  
Risk Of Injury ◽  
Increased Risk ◽  
Injury Protection

Purpose:To examine the association between combined session rating of perceived exertion (RPE) workload measures and injury risk in elite Gaelic footballers.Methods:Thirty-seven elite Gaelic footballers (mean ± SD age 24.2 ± 2.9 y) from 1 elite squad were involved in a single-season study. Weekly workload (session RPE multiplied by duration) and all time-loss injuries (including subsequent-wk injuries) were recorded during the period. Rolling weekly sums and wk-to-wk changes in workload were measured, enabling the calculation of the acute:chronic workload ratio by dividing acute workload (ie, 1-weekly workload) by chronic workload (ie, rolling-average 4-weekly workload). Workload measures were then modeled against data for all injuries sustained using a logistic-regression model. Odds ratios (ORs) were reported against a reference group.Results:High 1-weekly workloads (≥2770 arbitrary units [AU], OR = 1.63–6.75) were associated with significantly higher risk of injury than in a low-training-load reference group (<1250 AU). When exposed to spikes in workload (acute:chronic workload ratio >1.5), players with 1 y experience had a higher risk of injury (OR = 2.22) and players with 2–3 (OR = 0.20) and 4–6 y (OR = 0.24) of experience had a lower risk of injury. Players with poorer aerobic fitness (estimated from a 1-km time trial) had a higher injury risk than those with higher aerobic fitness (OR = 1.50–2.50). An acute:chronic workload ratio of (≥2.0) demonstrated the greatest risk of injury.Conclusions:These findings highlight an increased risk of injury for elite Gaelic football players with high (>2.0) acute:chronic workload ratios and high weekly workloads. A high aerobic capacity and playing experience appears to offer injury protection against rapid changes in workload and high acute:chronic workload ratios. Moderate workloads, coupled with moderate to high changes in the acute:chronic workload ratio, appear to be protective for Gaelic football players.

On- Versus Off-Bike Power Training in Professional Cyclists: A Randomized Controlled Trial

2020 ◽  
pp. 1-8 ◽  
Author(s):  
Pedro L. Valenzuela ◽  
Jaime Gil-Cabrera ◽  
Eduardo Talavera ◽  
Lidia B. Alejo ◽  
Almudena Montalvo-Pérez ◽  
...  
Keyword(s):  
Body Composition ◽  
Muscle Strength ◽  
Perceived Exertion ◽  
Ventilatory Threshold ◽  
Controlled Trial ◽  
Time Trial ◽  
Endurance Performance ◽  
Rating Of Perceived Exertion ◽  
Power Training ◽  
Sprint Training

Purpose: To compare the effectiveness of resistance power training (RPT, training with the individualized load and repetitions that maximize power output) and cycling power training (CPT, short sprint training) in professional cyclists. Methods: The participants (20 [2] y, peak oxygen uptake 78.0 [4.4] mL·kg−1·min−1) were randomly assigned to perform CPT (n = 8) or RPT (n = 10) in addition to their usual training regime for 7 weeks (2 sessions/wk). The training loads were continuously registered using the session rating of perceived exertion. The outcomes included endurance performance (8-min time trial and incremental test), as well as measures of muscle strength/power (1-repetition maximum and mean maximum propulsive power on the squat, hip thrust, and lunge exercises) and body composition (assessed by dual-energy X-ray absorptiometry). Results: No between-group differences were found for training loads or for any outcome (P > .05). Both interventions resulted in increased time-trial performance, as well as in improvements in other endurance-related outcomes (ie, ventilatory threshold, respiratory compensation point; P < .05). A significant or quasi-significant increase (P = .068 and .047 for CPT and RPT, respectively) in bone mineral content was observed after both interventions. A significant reduction in fat mass (P = .017), along with a trend (P = .059) toward a reduced body mass, was observed after RPT, but not CPT (P = .076 for the group × time interaction effect). Significant benefits (P < .05) were also observed for most strength-related outcomes after RPT, but not CPT. Conclusion: CPT and RPT are both effective strategies for the improvement of endurance performance and bone health in professional cyclists, although the latter tends to result in greater improvements in body composition and muscle strength/power.

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 The effect of low- vs high-cadence interval training on the freely chosen cadence and performance in endurance-trained cyclists

2016 ◽  
Vol 41 (6) ◽  
pp. 666-673 ◽  
Author(s):  
Anthony G. Whitty ◽  
Aron J. Murphy ◽  
Aaron J. Coutts ◽  
Mark L. Watsford
Keyword(s):  
Perceived Exertion ◽  
Average Power ◽  
Time Trial ◽  
Interval Training ◽  
Performance Measure ◽  
Rating Of Perceived Exertion ◽  
Superior Performance ◽  
Strength Development ◽  
And Performance ◽  
High Cadence

The aim of this study was to determine the effects of high- and low-cadence interval training on the freely chosen cadence (FCC) and performance in endurance-trained cyclists. Sixteen male endurance-trained cyclists completed a series of submaximal rides at 60% maximal power (Wmax) at cadences of 50, 70, 90, and 110 r·min−1, and their FCC to determine their preferred cadence, gross efficiency (GE), rating of perceived exertion, and crank torque profile. Performance was measured via a 15-min time trial, which was preloaded with a cycle at 60% Wmax. Following the testing, the participants were randomly assigned to a high-cadence (HC) (20% above FCC) or a low-cadence (LC) (20% below FCC) group for 18 interval-based training sessions over 6 weeks. The HC group increased their FCC from 92 to 101 r·min−1 after the intervention (p = 0.01), whereas the LC group remained unchanged (93 r·min−1). GE increased from 22.7% to 23.6% in the HC group at 90 r·min−1 (p = 0.05), from 20.0% to 20.9% at 110 r·min−1 (p = 0.05), and from 22.8% to 23.2% at their FCC. Both groups significantly increased their total distance and average power output following training, with the LC group recording a superior performance measure. There were minimal changes to the crank torque profile in both groups following training. This study demonstrated that the FCC can be altered with HC interval training and that the determinants of the optimal cycling cadence are multifactorial and not completely understood. Furthermore, LC interval training may significantly improve time-trial results of short duration as a result of an increase in strength development or possible neuromuscular adaptations.

Acute Ketone Supplementation and Exercise Performance: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

2020 ◽  
Vol 15 (3) ◽  
pp. 298-308 ◽  
Author(s):  
Pedro L. Valenzuela ◽  
Javier S. Morales ◽  
Adrián Castillo-García ◽  
Alejandro Lucia
Keyword(s):  
Randomized Controlled Trials ◽  
Exercise Performance ◽  
Perceived Exertion ◽  
Meta Analysis ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Controlled Trials ◽  
Glucose Levels ◽  
Randomized Controlled ◽  
Control Intervention

Purpose: To determine the acute effects of ketone supplementation on exercise performance (primary outcome) and physiological and perceptual responses to exercise (secondary outcomes). Methods: A systematic search was conducted in PubMed, Web of Science, and SPORTDiscus (since inception to July 21, 2019) to find randomized controlled trials assessing the effects of acute ketone supplementation compared with a drink containing no ketones (ie, control intervention). The standardized mean difference (Hedges g) between interventions and 95% confidence interval (CI) were computed using a random-effects model. Results: Thirteen studies met all inclusion criteria. No significant differences were observed between interventions for overall exercise performance (Hedges g = −0.05; 95% CI, −0.30 to 0.20; P = .68). Subanalyses revealed no differences between interventions when analyzing endurance time-trial performance (g = −0.04; 95% CI, −0.35 to 0.28; P = .82) or when assessing the separate effects of supplements containing ketone esters (g = −0.07; 95% CI, −0.38 to 0.24; P = .66) or salts (g = −0.02; 95% CI, −0.45 to 0.41; P = .93). All studies reported increases in plasma ketone concentration after acute ketone supplementation, but no consistent effects were reported on the metabolic (plasma lactate and glucose levels), respiratory (respiratory exchange ratio, oxygen uptake, and ventilatory rate), cardiovascular (heart rate), or perceptual responses to exercise (rating of perceived exertion). Conclusions: The present findings suggest that ketone supplementation exerts no clear influence on exercise performance (from sprints to events lasting up to ∼50 min) or metabolic, respiratory, cardiovascular, or perceptual responses to exercise. More research is needed to elucidate if this strategy could provide ergogenic effects on other exercise types (eg, ultraendurance exercise).

A synthetic undergarment increases physiological strain

2019 ◽  
Vol 28 (4) ◽  
pp. 275 ◽  
Author(s):  
Matthew C. Dorton ◽  
Brent C. Ruby ◽  
Charles L. Dumke
Keyword(s):  
Blood Flow ◽  
Skin Blood Flow ◽  
Perceived Exertion ◽  
Sweat Rate ◽  
Rest Period ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Physiological Strain ◽  
Physiological Factors ◽  
Increased Risk

Our aim was to examine the effect of a synthetic material undergarment on heat stress during exercise in a hot environment. Ten active males completed two trials of intermittent (50min walking, 10min sitting) treadmill walking over 3h in 35°C and 30% relative humidity. Subjects wore wildland firefighter flame-resistant meta-aramid blend pants and shirt with either a 100% cotton (C) or flame-retardant modacrylic undergarment (S), while carrying a 16-kg pack, helmet and leather gloves. Exercise was followed by a 30-min rest period without pack, helmet, gloves, and outerwear shirt. Rectal temperature and physiological strain were greater in S than C (P=0.04). No significant differences were found for heart rate, rating of perceived exertion, energy expenditure or skin temperature between C and S. Skin blood flow increased significantly in S following the second hour of exercise, resulting in a time×trial interaction (P=0.001). No significant differences for skin blood flow were found post exercise. Sweat rate and percent dehydration were not different between C and S. These data indicate that, of the two undergarments investigated, the synthetic undergarment negatively affected physiological factors that have been shown to indicate an increased risk of heat-related injuries.

Carbohydrate Mouth Rinsing in the Fed State: Lack of Enhancement of Time-Trial Performance

2009 ◽  
Vol 19 (4) ◽  
pp. 400-409 ◽  
Author(s):  
Milou Beelen ◽  
Jort Berghuis ◽  
Ben Bonaparte ◽  
Sam B. Ballak ◽  
Asker E. Jeukendrup ◽  
...  
Keyword(s):  
Heart Rate ◽  
Power Output ◽  
Perceived Exertion ◽  
Average Power ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Time Trial Performance ◽  
Mouth Rinsing ◽  
The Impact ◽  
Trial Performance

It has been reported previously that mouth rinsing with a carbohydrate-containing solution can improve cycling performance. The purpose of the current study was to investigate the impact of such a carbohydrate mouth rinse on exercise performance during a simulated time trial in a more practical, postprandial setting. Fourteen male endurance-trained athletes were selected to perform 2 exercise tests in the morning after consuming a standardized breakfast. They performed an ~1-hr time trial on a cycle ergometer while rinsing their mouths with either a 6.4% maltodextrin solution (CHO) or water (PLA) after every 12.5% of the set amount of work. Borg’s rating of perceived exertion (RPE) was assessed after every 25% of the set amount of work, and power output and heart rate were recorded continuously throughout the test. Performance time did not differ between treatments and averaged 68.14 ± 1.14 and 67.52 ± 1.00 min in CHO and PLA, respectively (p = .57). In accordance, average power output (265 ± 5 vs. 266 ± 5 W, p = .58), heart rate (169 ± 2 vs. 168 ± 2 beats/min, p = .43), and RPE (16.4 ± 0.3 vs. 16.7 ± 0.3 W, p = .26) did not differ between treatments. Furthermore, after dividing the trial into 8s, no differences in power output, heart rate, or perceived exertion were observed over time between treatments. Carbohydrate mouth rinsing does not improve time-trial performance when exercise is performed in a practical, postprandial setting.

Effects of Varying Post-Warm-Up Recovery Time on 200-m Time-Trial Swim Performance

2007 ◽  
Vol 2 (2) ◽  
pp. 201-211 ◽  
Author(s):  
Thomas Zochowski ◽  
Elizabeth Johnson ◽  
Gordon G. Sleivert
Keyword(s):  
Heart Rate ◽  
Blood Lactate ◽  
Recovery Time ◽  
Perceived Exertion ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Warm Up ◽  
Swimming Time ◽  
Time Trial Performance ◽  
Trial Performance

Context:Warm-up before athletic competition might enhance performance by affecting various physiological parameters. There are few quantitative data available on physiological responses to the warm-up, and the data that have been reported are inconclusive. Similarly, it has been suggested that varying the recovery period after a standardized warm-up might affect subsequent performance.Purpose:To determine the effects of varying post-warm-up recovery time on a subsequent 200-m swimming time trial.Methods:Ten national-caliber swimmers (5 male, 5 female) each swam a 1500-m warm-up and performed a 200-m time trial of their specialty stroke after either 10 or 45 min of passive recovery. Subjects completed 1 time trial in each condition separated by 1 wk in a counterbalanced order. Blood lactate and heart rate were measured immediately after warm-up and 3 min before, immediately after, and 3 min after the time trial. Rating of perceived exertion was measured immediately after the warm-up and time trial.Results:Time-trial performance was significantly improved after 10 min as opposed to 45 min recovery (136.80 ± 20.38 s vs 138.69 ± 20.32 s, P < .05). There were no significant differences between conditions for heart rate and blood lactate after the warm-up. Pre-time-trial heart rate, however, was higher in the 10-min than in the 45-min rest condition (109 ± 14 beats/min vs 94 ± 21 beats/min, P < .05).Conclusions:A post-warm-up recovery time of 10 min rather than 45 min is more beneficial to 200-m swimming time-trial performance.

scholarly journals Intra-Subject Variability of 5 Km Time Trial Performance Completed by Competitive Trained Runners

2017 ◽  
Vol 57 (1) ◽  
pp. 139-146 ◽  
Author(s):  
James Fisher ◽  
Thomas Clark ◽  
Katherine Newman-Judd ◽  
Josh Arnold ◽  
James Steele
Keyword(s):  
Heart Rate ◽  
Correlation Coefficient ◽  
Perceived Exertion ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Intra Class Correlation ◽  
Subject Variability ◽  
Trained Runners ◽  
Intra Class Correlation Coefficient ◽  
Trial Performance

AbstractTime-trials represent an ecologically valid approach to assessment of endurance performance. Such information is useful in the application of testing protocols and estimation of sample sizes required for research/magnitude based inference methods. The present study aimed to investigate the intra-subject variability of 5 km time-trial running performance in trained runners. Six competitive trained male runners (age = 33.8 ± 10.1 years; stature = 1.78 ± 0.01 m; body mass = 69.0 ± 10.4 kg, $\it V^{.}$ O2max = 62.6 ± 11.0 ml·kg·min-1) completed an incremental exercise test to volitional exhaustion followed by 5 x 5 km time-trials (including a familiarisation trial), individually spaced by 48 hours. The time taken to complete each trial, heart rate, rating of perceived exertion and speed were all assessed. Intra-subject absolute standard error of measurement and the coefficient of variance were calculated for time-trial variables in addition to the intra-class correlation coefficient for time taken to complete the time-trial. For the primary measure time, results showed a coefficient of variation score across all participants of 1.5 ± 0.59% with an intra-class correlation coefficient score of 0.990. Heart rate, rating of perceived exertion and speed data showed a variance range between 0.8 and 3.05%. It was concluded that when compared with related research, there was observed low intra-subject variability in trained runners over a 5 km distance. This supports the use of this protocol for 5 km time-trial performance for assessment of nutritional strategies, ergogenic aids or training interventions on endurance running performance.

Cycling Attributes That Enhance Running Performance After the Cycle Section in Triathlon

2013 ◽  
Vol 8 (5) ◽  
pp. 502-509 ◽  
Author(s):  
Naroa Etxebarria ◽  
Judith M. Anson ◽  
David B. Pyne ◽  
Richard A. Ferguson
Keyword(s):  
Power Distribution ◽  
Perceived Exertion ◽  
Time Trial ◽  
Rating Of Perceived Exertion ◽  
Specific Power ◽  
Mean Power ◽  
Running Performance ◽  
Power Profile ◽  
Variable Power ◽  
Run Time

Purpose:To determine how cycling with a variable (triathlon-specific) power distribution affects subsequent running performance and quantify relationships between an individual cycling power profile and running ability after cycling.Methods:Twelve well-trained male triathletes (VO2peak 4.9 ± 0.5 L/min; mass 73.5 ± 7.7 kg; mean ± SD) undertook a cycle VO2peak and maximal aerobic power (MAP) test and a power profile involving 6 maximal efforts (6 s to 10 min). Each subject then performed 2 experimental 1-h cycle trials, both at a mean power of 65% MAP, at either variable power (VAR) ranging from 40% to 140% MAP or constant power (CON) followed by an outdoor 9.3-km time-trial run. Subjects also completed a control 9.3-km run with no preceding exercise.Results:The 9.3-km run time was 42 ± 37 s slower (mean ± 90% confidence limits [CL]) after VAR (35:32 ± 3:18 min:s, mean ± SD) compared with CON cycling (34:50 ± 2:49 min:s). This decrement after VAR appeared primarily in the first half of the run (35 ± 20 s; mean ± 90% CL). Higher blood lactate and rating of perceived exertion after 1 h VAR cycling were moderately correlated (r = .51–.55; ± ~.40) with a larger decrement in run performance. There were no clear associations between the power-profile test and decrement in run time after VAR compared with CON.Conclusions:A highly variable power distribution in cycling is likely to impair 10-km triathlon run performance. Training to lower physiological and perceptual responses during cycling should limit the negative effects on triathlon running.

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