Allometric scaling of peak power output accurately predicts time trial performance and maximal oxygen consumption in trained cyclists

Purpose:Aerobic economy is an important factor that affects the performance of competitive cyclists. It has been suggested that placing the foot more anteriorly on the bicycle pedals may improve economy over the traditional foot position by improving pedaling efficiency. The current study examines the effects of changing the anterior-posterior pedal foot position on the physiology and performance of well-trained cyclists.Methods:In a crossover study, 10 competitive cyclists completed two maximal incremental and two submaximal tests in either their preferred (control) or a forward (arch) foot position. Maximum oxygen consumption and peak power output were determined from the incremental tests for both foot positions. On two further occasions, cyclists also completed a two-part 60-min submaximal test that required them to maintain a constant power output (equivalent to 60% of their incremental peak power) for 30 min, during which respiratory and blood lactate samples were taken at predetermined intervals. Thereafter, subjects completed a 30-min self-paced maximal effort time trial.Results:Relative to the control, the mean changes (±90% confidence limits) in the arch condition were as follows: maximum oxygen consumption, -0.5% (±2.0%); incremental peak power output, -0.8% (±1.3%); steady-state oxygen consumption at 60%, -2.4% (±1.1%); steady-state heart rate 60%, 0.4% (±1.7%); lactate concentration 60%, 8.7% (±14.4%); and mean time trial power, -1.5% (±2.9%).Conclusions:We conclude that there was no substantial physiological or performance advantage in this group using an arch-cleat shoe position in comparison with a cyclist’s normal preferred condition.

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

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.19.4.400 ◽

2009 ◽

Vol 19 (4) ◽

pp. 400-409 ◽

Cited By ~ 82

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.

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Influence of Environmental Temperature on 40 km Cycling Time-Trial Performance

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.6.2.208 ◽

2011 ◽

Vol 6 (2) ◽

pp. 208-220 ◽

Cited By ~ 38

Author(s):

Jeremiah J. Peiffer ◽

Chris R. Abbiss

Keyword(s):

Core Temperature ◽

Power Output ◽

Environmental Temperature ◽

Core Body Temperature ◽

Time Trial ◽

Time Trial Performance ◽

Cycling Time Trial ◽

Pacing Strategies ◽

Cycling Time ◽

Trial Performance

The purpose of this study was to examine the effect of environmental temperature on variability in power output, self-selected pacing strategies, and performance during a prolonged cycling time trial. Nine trained male cyclists randomly completed four 40 km cycling time trials in an environmental chamber at 17°C, 22°C, 27°C, and 32°C (40% RH). During the time trials, heart rate, core body temperature, and power output were recorded. The variability in power output was assessed with the use of exposure variation analysis. Mean 40 km power output was significantly lower during 32°C (309 ± 35 W) compared with 17°C (329 ± 31 W), 22°C (324 ± 34 W), and 27°C (322 ± 32 W). In addition, greater variability in power production was observed at 32°C compared with 17°C, as evidenced by a lower (P = .03) standard deviation of the exposure variation matrix (2.9 ± 0.5 vs 3.5 ± 0.4 units, respectively). Core temperature was greater (P < .05) at 32°C compared with 17°C and 22°C from 30 to 40 km, and the rate of rise in core temperature throughout the 40 km time trial was greater (P < .05) at 32°C (0.06 ± 0.04°C·km–1) compared with 17°C (0.05 ± 0.05°C·km–1). This study showed that time-trial performance is reduced under hot environmental conditions, and is associated with a shift in the composition of power output. These finding provide insight into the control of pacing strategies during exercise in the heat.

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Enhanced Cycling Time-Trial Performance During Multiday Exercise With Higher-Pressure Compression Garment Wear

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2019-0716 ◽

2020 ◽

pp. 1-9

Author(s):

Ewan R. Williams ◽

James McKendry ◽

Paul T. Morgan ◽

Leigh Breen

Keyword(s):

Heart Rate ◽

Creatine Kinase ◽

Oxygen Consumption ◽

Time Trial ◽

Plasma Lactate ◽

Compression Garments ◽

Time Trial Performance ◽

Cycling Time Trial ◽

Cycling Time ◽

Trial Performance

Purpose: Compression garments are widely used as a tool to accelerate recovery from intense exercise and have also gained traction as a performance aid, particularly during periods of limited recovery. This study tested the hypothesis that increased pressure levels applied via high-pressure compression garments would enhance “multiday” exercise performance. Methods: A single-blind crossover design, incorporating 3 experimental conditions—loose-fitting gym attire (CON), low-compression (LC), and high-compression (HC) garments—was adopted. A total of 10 trained male cyclists reported to the laboratory on 6 occasions, collated into 3 blocks of 2 consecutive visits. Each “block” consisted of 3 parts, an initial high-intensity protocol, a 24-hour period of controlled rest while wearing the applied condition/garment (CON, LC, and HC), and a subsequent 8-km cycling time trial, while wearing the respective garment. Subjective discomfort questionnaires and blood pressure were assessed prior to each exercise bout. Power output, oxygen consumption, and heart rate were continuously measured throughout exercise, with plasma lactate, creatine kinase, and myoglobin concentrations assessed at baseline and the end of exercise, as well as 30 and 60 minutes postexercise. Results: Time-trial performance was significantly improved during HC compared with both CON and LC (HC = 277 [83], CON = 266 [89], and LC = 265 [77] W; P < .05). In addition, plasma lactate was significantly lower at 30 and 60 minutes postexercise on day 1 in HC compared with CON. No significant differences were observed for oxygen consumption, heart rate, creatine kinase, or subjective markers of discomfort. Conclusion: The pressure levels exerted via lower-limb compression garments influence their effectiveness for cycling performance, particularly in the face of limited recovery.

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A Comparison of Different Prerace Warm-Up Strategies on 1-km Cycling Time-Trial Performance

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2019-0557 ◽

2020 ◽

Vol 15 (8) ◽

pp. 1109-1116

Author(s):

Mathias T. Vangsoe ◽

Jonas K. Nielsen ◽

Carl D. Paton

Keyword(s):

Blood Lactate ◽

Power Output ◽

Peak Power ◽

Lactate Concentration ◽

Blood Lactate Concentration ◽

Time Trial ◽

Peak Power Output ◽

Warm Up ◽

Performance Time ◽

Competitive Cyclists

Purpose: Ischemic preconditioning (IPC) and postactivation potentiation (PAP) are warm-up strategies proposed to improve high-intensity sporting performance. However, only few studies have investigated the benefits of these strategies compared with an appropriate control (CON) or an athlete-selected (SELF) warm-up protocol. Therefore, this study examined the effects of 4 different warm-up routines on 1-km time-trial (TT) performance with competitive cyclists. Methods: In a randomized crossover study, 12 well-trained cyclists (age 32 [10] y, mass 77.7 [4.6] kg, peak power output 1141 [61] W) performed 4 different warm-up strategies—(CON) 17 minutes CON only, (SELF) a self-determined warm-up, (IPC) IPC + CON, or (PAP) CON + PAP—prior to completing a maximal-effort 1-km TT. Performance time and power, quadriceps electromyograms, muscle oxygen saturation (SmO2), and blood lactate were measured to determine differences between trials. Results: There were no significant differences (P > .05) in 1-km performance time between CON (76.9 [5.2] s), SELF (77.3 [6.0] s), IPC (77.0 [5.5] s), or PAP (77.3 [5.9] s) protocols. Furthermore, there were no significant differences in mean or peak power output between trials. Finally, electromyogram activity, SmO2, and recovery blood lactate concentration were not different between conditions. Conclusions: Adding IPC or PAP protocols to a short CON warm-up appears to provide no additional benefit to 1-km TT performance with well-trained cyclists and is therefore not recommended. Furthermore, additional IPC and PAP protocols had no effect on electromyograms and SmO2 values during the TT or peak lactate concentration during recovery.

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Training Prescription Guided by Heart-Rate Variability in Cycling

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2018-0122 ◽

2019 ◽

Vol 14 (1) ◽

pp. 23-32 ◽

Cited By ~ 13

Author(s):

Alejandro Javaloyes ◽

Jose Manuel Sarabia ◽

Robert Patrick Lamberts ◽

Manuel Moya-Ramon

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Oxygen Uptake ◽

Power Output ◽

Maximal Oxygen Uptake ◽

Peak Power ◽

Performance Enhancement ◽

Time Trial ◽

Peak Power Output ◽

Road Cycling

Purpose: Road cycling is a sport with extreme physiological demands. Therefore, there is a need to find new strategies to improve performance. Heart-rate variability (HRV) has been suggested as an effective alternative for prescribing training load against predefined training programs. The purpose of this study was to examine the effect of training prescription based on HRV in road cycling performance. Methods: Seventeen well-trained cyclists participated in this study. After an initial evaluation week, cyclists performed 4 baseline weeks of standardized training to establish their resting HRV. Then, cyclists were divided into 2 groups, an HRV-guided group and a traditional periodization group, and they carried out 8 training weeks. Cyclists performed 2 evaluation weeks, after and before a training week. During the evaluation weeks, cyclists performed a graded exercise test to assess maximal oxygen uptake, peak power output, and ventilatory thresholds with their corresponding power output (VT1, VT2, WVT1, and WVT2, respectively) and a 40-min simulated time trial. Results: The HRV-guided group improved peak power output (5.1% [4.5%]; P = .024), WVT2 (13.9% [8.8%]; P = .004), and 40-min all-out time trial (7.3% [4.5%]; P = .005). Maximal oxygen uptake and WVT1 remained similar. The traditional periodization group did not improve significantly after the training week. There were no differences between groups. However, magnitude-based inference analysis showed likely beneficial and possibly beneficial effects for the HRV-guided group instead of the traditional periodization group in 40-min all-out time trial and peak power output, respectively. Conclusion: Daily training prescription based on HRV could result in a better performance enhancement than a traditional periodization in well-trained cyclists.

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Determinants of time trial performance and maximal incremental exercise in highly trained endurance athletes

Journal of Applied Physiology ◽

10.1152/japplphysiol.00625.2011 ◽

2011 ◽

Vol 111 (5) ◽

pp. 1422-1430 ◽

Cited By ~ 87

Author(s):

R. A. Jacobs ◽

P. Rasmussen ◽

C. Siebenmann ◽

V. Díaz ◽

M. Gassmann ◽

...

Keyword(s):

Skeletal Muscle ◽

Oxidative Phosphorylation ◽

Power Output ◽

Vastus Lateralis ◽

Average Power ◽

Time Trial ◽

Vastus Lateralis Muscle ◽

Time Trial Performance ◽

Principal Factors ◽

Trial Performance

Human endurance performance can be predicted from maximal oxygen consumption (V̇o2max), lactate threshold, and exercise efficiency. These physiological parameters, however, are not wholly exclusive from one another, and their interplay is complex. Accordingly, we sought to identify more specific measurements explaining the range of performance among athletes. Out of 150 separate variables we identified 10 principal factors responsible for hematological, cardiovascular, respiratory, musculoskeletal, and neurological variation in 16 highly trained cyclists. These principal factors were then correlated with a 26-km time trial and test of maximal incremental power output. Average power output during the 26-km time trial was attributed to, in order of importance, oxidative phosphorylation capacity of the vastus lateralis muscle ( P = 0.0005), steady-state submaximal blood lactate concentrations ( P = 0.0017), and maximal leg oxygenation (sO2LEG) ( P = 0.0295), accounting for 78% of the variation in time trial performance. Variability in maximal power output, on the other hand, was attributed to total body hemoglobin mass (Hbmass; P = 0.0038), V̇o2max ( P = 0.0213), and sO2LEG ( P = 0.0463). In conclusion, 1) skeletal muscle oxidative capacity is the primary predictor of time trial performance in highly trained cyclists; 2) the strongest predictor for maximal incremental power output is Hbmass; and 3) overall exercise performance (time trial performance + maximal incremental power output) correlates most strongly to measures regarding the capability for oxygen transport, high V̇o2max and Hbmass, in addition to measures of oxygen utilization, maximal oxidative phosphorylation, and electron transport system capacities in the skeletal muscle.

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The Effects of Carbohydrate and Caffeine Mouth Rinsing on Arm Crank Time-Trial Performance

Journal of Sports Research ◽

10.18488/journal.90/2014.1.2/90.2.34.44 ◽

2015 ◽

Vol 1 (2) ◽

pp. 34-44

Author(s):

Jonathan Sinclair ◽

Lindsay Bottoms

Keyword(s):

Power Output ◽

Perceived Exertion ◽

Time Trial ◽

Mouth Rinse ◽

Current Investigation ◽

Ratings Of Perceived Exertion ◽

Arm Cranking ◽

Time Trial Performance ◽

Mouth Rinsing ◽

Trial Performance

This study aimed to determine whether carbohydrate (CHO) and caffeine (CAFF) mouth rinsing would improve 30 minute arm cranking time-trial performance. Twelve male participants (age 21.54 ± 1.28 years, height 179.46 ± 7.38 cm and mass 73.69 ± 5.40 kg) took part in the current investigation. Participants came to the laboratory on 3 occasions during which they performed 30 minute self-paced arm crank time trials. On one occasion water was given as a mouth rinse for 5 s (PLA), on another occasion a 6.4% CHO solution was given for 5 s and finally a 0.032% CAFF solution was given for 5s. Key measurements of distance covered, heart rate (HR), ratings of perceived exertion (RPE), cadence and power output were recorded throughout all trials. Distance covered during the CAFF (15.43 ± 3.27 km) and CHO (15.30 ± 3.31) mouth rinse trials were significantly (p<0.05) greater in comparison to PLA (13.15 ± 3.36 km). Cadence and power output and velocity were also significantly greater during the CAFF and CHO trials compared to PLA and CHO (p<0.05). No significant (P>0.05) differences between trials were observed for HR and RPE. CAFF and CHO mouth rinse serve to improve 30 minute arm cranking performance by mediating increasing cadence and power output without a concurrent increase in RPE and HR.

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