Performance In Competitive Cyclists Research Articles

Effect of Clothing Fabric on 20-km Cycling Performance in Endurance Athletes.

Purpose: Examine the effect of synthetic fabrics (SYN, 60% polyester: 40% nylon) vs. 100% cotton fabric (CTN) on the 20-km cycling time trial (20 kmCTT) performance of competitive cyclists and triathletes.Methods: In this randomized controlled crossover study, 15 adults (5 women) aged 29.6 ± 2.7 years (mean ± SE) with a peak rate of O2 consumption of 60.0 ± 2.0 ml/kg/min completed a 20 kmCTT under ambient laboratory conditions (24.3 ± 0.7°C and 17 ± 7% relative humidity) with a simulated wind of ~3 m/s while wearing SYN or CTN clothing ensembles. Both ensembles were of snowflake mesh bi-layer construction and consisted of a loose-fitting long-sleeved shirt with full-length trousers.Results: Participants maintained a significantly (p < 0.05) higher cycling speed and power output over the last 6-km of the 20 kmCTT while wearing the SYN vs. CTN ensemble (e.g., by 0.98 km/h and 18.4 watts at the 20-km mark). Consequently, 20 kmCTT duration was significantly reduced by 15.7 ± 6.8 sec or 0.8 ± 0.3% during SYN vs. CTN trials (p < 0.05). Improved 20 kmCTT performance with SYN vs. CTN clothing could not be explained by concurrent differences in esophageal temperature, sweat rate, ratings of perceived exertion and/or cardiometabolic responses to exercise. However, it was accompanied by significantly lower mean skin temperatures (~1°C) and more favorable ratings of perceived clothing comfort and thermal sensation during exercise.Conclusion: Under the experimental conditions of the current study, athletic clothing made of synthetic fabrics significantly improved the 20 kmCTT performance of endurance-trained athletes by optimizing selected thermoregulatory and perceptual responses to exercise.

Flattened cola improves high-intensity interval performance in competitive cyclists.

Some cyclists consume flattened cola during competitive events, but limited research has investigated if cola beverages elicit ergogenic effects, particularly on high-intensity exercise performance. Whether the potentially beneficial effects of cola are due to the caffeine and/or the carbohydrate content is also unclear. This study assessed the ergogenic effects of different cola beverages on performance during a constant power bout (CPB) and subsequent high-intensity interval efforts in competitive cyclists. In a randomized, double-blind, cross-over design, competitive cyclists (n = 13; [Formula: see text]O2max 65.7 ± 5.9mlkg-1min-1) completed a 45-min CPB at 69% of maximum workload (Wmax), followed by four maximal 1-min high-intensity intervals (HII) against a resistance of 0.5Nkg-1. Participants consumed 16mlkg-1 total (intermittantly at four time points) of flattened decaffinated diet cola (PLA), caffeinated diet cola (CAF) or cola containing caffeine and carbohydrates (CAF + CHO). During the CPB, ratings of perceived exertion were lower in the CAF + CHO and CAF conditions compared to PLA (both, P < 0.04). Compared to PLA, CAF + CHO and CAF similarly increased (all, P < 0.049) mean power (CAF + CHO: 448 ± 51W; CAF: 448 ± 50W; PLA: 434 ± 57W), minimum power (CAF + CHO: 353 ± 45W; CAF: 352 ± 51W; PLA: 324 ± 49W) and total work (CAF + CHO: 26.9 ± 3.1kJ; CAF: 26.9 ± 3.0kJ; PLA: 26.0 ± 3.4kJ), but not peak power (CAF + CHO: 692 ± 117W; CAF: 674 ± 114W; PLA: 670 ± 113W; all, P > 0.57) during the HII. Cola containing caffeine with or without carbohydrates favorably influenced perceived effort during the CPB and enhanced mean and minimum power during repeated maximal intervals. We provide evidence supporting the consumption of commercially available cola for high-intensity cycling in competitive cyclists.

The acute effects of lower limb blood flow restriction on physiology and performance of competitive cyclists

Background: Training in conjunction with limb Blood flow restriction (BFR) is an increasingly popular method of producing increased physiological stress without the strain of high exercise loads. However little is known about the physiological responses to BFR with trained cyclists or how best to prescribe appropriate BFR training intensities. Purpose: In this study, we investigate the acute responses to different levels of BFR with trained cyclists to enable identification of specific training intensity criteria. Methods: Nine trained male cyclist (age 39.2 ± 8.1 years, height 179.1 ± 6.7 cm, weight 75.4 ± 6.7 kg, Max VO 2 4.4 ± 0.5 L.min -1 ) completed a series of tests under conditions of no BFR (N-BFR; 0mmHg), moderate BFR (M-BFR; ~40mmHg) or high BFR (H-BFR; ~80mmHg). During BFR trials restriction was applied to the proximal thighs using 11cm wide pneumatic cuffs. Testing consisted of an incremental maximal cycle test and a self-paced 3-km time-trial. Measurement of Oxygen uptake (VO 2 ), Muscle Oxygen saturation (MO 2 ) blood lactate concentration (Bla) and perceived exertion (RPE) were taken during the incremental test along with performance data from the time trial.  Physiological responses from the three trials were examined across a range of comparable power outputs and at pre-determined blood lactate concentrations of 2 and 4 Mmol. Results: At comparable power outputs, heart rate and RPE was significantly higher (p>0.05) in the H-BFR condition compared to all other conditions. However, there were no significant differences between conditions in VO 2 and MO 2 at equivalent powers. Compared to the N-BFR condition power output was lower by ~9% and ~21 % in the M-BFR and H-BFR condition respectively (fig 1) for fixed blood lactate concentration of 2 and 4mMol. Discussion: Using moderate and high levels of BFR during cycling exercise leads to substantial reductions (left shift) in power output at fixed blood lactate values. The reduced power was associated with increases in heart rate and RPE, at equivalent power outputs. However, measures of O 2 and MO 2 were not significantly different at comparable exercise intensities between the conditions. Conclusions: the decrease in attainable power output in BFR conditions appears predominately due to an increased reliance on anaerobic metabolism and an elevation in blood lactate concentration. Cardiovascular O2 delivery and extraction does not appear to be significantly affected by BFR. Â

Histamine-Receptor Antagonists Slow 10-km Cycling Performance in Competitive Cyclists.

Determine the effects of histamine-receptor antagonism on cycling time trial performance in humans, with and without a preceding bout of sustained steady-state exercise. Eleven (3F) competitive cyclists performed six 10-km time trials on separate days. The first two time trials served as familiarization. The next four time trials were performed in randomized-block order, where two were preceded by 120 min of seated rest (rest) and two by 120 min of cycling exercise (Exercise) at 50% V˙O2peak. Within each block, subjects consumed either combined histamine H1 and H2 receptor antagonists (Blockade) or Placebo, before the start of the 120-min Rest/Exercise. Blockade had no discernible effects on hemodynamic or metabolic variables during Rest or Exercise. However, Blockade increased time-to-completion of the 10-km time trial compared with Placebo (+10.5 ± 3.7 s, P < 0.05). Slowing from placebo to blockade was not different between rest (+8.7 ± 5.2 s) and Exercise (+12.3 ± 5.8 s, P = 0.716). Exercise-related histaminergic signaling appears inherent to endurance exercise and may play a role in facilitating optimal function during high-intensity endurance exercise.

A Monetary Reward Alters Pacing but Not Performance in Competitive Cyclists.

Money has frequently been used as an extrinsic motivator since it is assumed that humans are willing to invest more effort for financial reward. However, the influence of a monetary reward on pacing and performance in trained athletes is not well-understood. Therefore, the aim of this study was to analyse the influence of a monetary reward in well-trained cyclists on their pacing and performance during short and long cycling time trials (TT). Twentythree cyclists (6 ♀, 17 ♂) completed 4 self-paced time trials (TTs, 2 short: 4 km and 6 min; 2 long: 20 km and 30 min); in a randomized order. Participants were separated into parallel, non-randomized “rewarded” and “non-rewarded” groups. Cyclists in the rewarded group received a monetary reward based on highest mean power output across all TTs. Cyclists in the non-rewarded group did not receive a monetary reward. Overall performance was not significantly different between groups in short or long TTs (p > 0.48). Power output showed moderatly lower effect sizes at comencement of the short TTs (Pmeandiff = 36.6 W; d > 0.44) and the 20 km TT (Pmeandiff = 22.6 W; d = 0.44) in the rewarded group. No difference was observed in pacing during the 30 min TT (p = 0.95). An external reward seems to have influenced pacing at the commencement of time trials. Participants in the non-rewarded group adopted a typical parabolic shaped pattern, whereas participants in the rewarded group started trials more conservatively. Results raise the possibility that using money as an extrinsic reward may interfere with regulatory processes required for effective pacing.

Parameters of the 3-Minute All-Out Test: Overestimation of Competitive-Cyclist Time-Trial Performance in the Severe-Intensity Domain.

To verify the accuracy of predicting performance in the severe-intensity domain by means of end-test power output (EP) and the work performed above EP (WEP) obtained from a 3-min all-out test in competitive cyclists. Ten welltrained cyclists performed a ramp incremental test and a 3-min all-out familiarization test. Subsequently, they performed a 3-min all-out experimental test to obtain EP and WEP and a 10-min time trial (TT). The actual 10-min-TT mean power output was then compared with the power output predicted as P = WEP/Tlim + EP, where Tlim corresponds to 600 s. The ramp-test peak power output (PPO) was compared with PPO predicted as [Formula: see text], where S represents the ramp slope (0.5 W/s). The actual (347 ± 30 W) and predicted (376 ± 48 W) 10-min TT mean power output were correlated (r = .87, P = .001) but significantly different (P < .01). The coefficient of variation (CV) between the predicted and actual performance was 5.6% ± 4.4%. The error of prediction was positively correlated to EP (r = .80, P = .005) and negatively correlated to WEP (r = -.71, P = .021). No significant difference was found between the 10-min-TT mean power output and EP (351 ± 53 W). The actual (438 ± 30 W) and predicted (472 ± 41 W) ramp PPO were correlated (r = .88, P < .001) but significantly different (P < .001). The CV between the predicted and actual PPO was 5.2% ± 3%. The error of prediction was positively correlated to EP (r = .63, P = .051). EP and WEP obtained from a 3-min all-out test overestimate severe-intensity performance in competitive cyclists.

Performance effects of acute β-alanine induced paresthesia in competitive cyclists

β-alanine is a common ingredient in supplements consumed by athletes. Indeed, athletes may believe that the β-alanine induced paresthesia, experienced shortly after ingestion, is associated with its ergogenic effect despite no scientific mechanism supporting this notion. The present study examined changes in cycling performance under conditions of β-alanine induced paresthesia. Eight competitive cyclists (VO2max = 61.8 ± 4.2 mL·kg·min−1) performed three practices, one baseline and four experimental trials. The experimental trials comprised a 1-km cycling time trial under four conditions with varying information (i.e., athlete informed β-alanine or placebo) and supplement content (athlete received β-alanine or placebo) delivered to the cyclist: informed β-alanine/received β-alanine, informed placebo/received β-alanine, informed β-alanine/received placebo and informed placebo/received placebo. Questionnaires were undertaken exploring the cyclists’ experience of the effects of the experimental conditions. A possibly likely increase in mean power was associated with conditions in which β-alanine was administered (±95% CL: 2.2% ± 4.0%), but these results were inconclusive for performance enhancement (p = 0.32, effect size = 0.18, smallest worthwhile change = 56% beneficial). A possibly harmful effect was observed when cyclists were correctly informed that they had ingested a placebo (–1.0% ± 1.9%). Questionnaire data suggested that β-alanine ingestion resulted in evident sensory side effects and six cyclists reported placebo effects. Acute ingestion of β-alanine is not associated with improved 1-km TT performance in competitive cyclists. These findings are in contrast to the athlete’s “belief” as cyclists reported improved energy and the ability to sustain a higher power output under conditions of β-alanine induced paresthesia.

Nitrate supplementation and high-intensity performance in competitive cyclists.

Consumption of inorganic nitrate (NO3(-)) is known to enhance endurance exercise performance in recreationally trained subjects. Here we report the effect on a high-intensity performance task in national-level cyclists. The performance test consisted of 2 cycle ergometer time trials of 4 min duration with 75 min between trials. In a randomized crossover design, 26 cyclists performed the test under the following 4 conditions (each separated by a 6-day washout): consumption of 70 mL of nitrate-rich beetroot juice at 150 min or 75 min before the first time trial, addition of a 35 mL "top-up dose" following the first time trial in the 150 min condition, and consumption of a placebo. A linear mixed model with adjustments for learning effects and athlete fitness (peak incremental power) was used to estimate effects on mean power, with probabilistic inferences based on a smallest important effect of 1.0%. Peak plasma nitrite (NO2(-)) concentration was greatest when nitrate was taken 75 min before the first time trial. Relative to placebo, the mean effect of all 3 nitrate treatments was unclear in the first time trial (1.3%, 90% confidence limits: ±1.7%), but possibly harmful in the second time trial (-0.3%, ±1.6%). Differences between nitrate treatments were unclear, as was the estimate of any consistent individual response to the treatments. Allowing for sampling uncertainty, the effect of nitrate on performance was less than previous studies. Under the conditions of our experiment, nitrate supplementation may be ineffective in facilitating high-intensity exercise in competitive athletes.

The effects of 6-week-decoupled bi-pedal cycling on submaximal and high intensity performance in competitive cyclists and triathletes

Aim of this work was to examine the effects of decoupled two-legged cycling on (1) submaximal and maximal oxygen uptake, (2) power output at 4mmolL(-1) blood lactate concentration, (3) mean and peak power output during high intensity cycling (30s sprint) and (4) isometric and dynamic force production of the knee extensor and flexor muscles. 18 highly trained male competitive male cyclists and triathletes (age 24±3years; body height 179±11cm; body mass 78±8kg; peak oxygen uptake 5,070±680mL min(-1)) were equally randomized to exercise on a stationary cycle equipped either with decoupled or with traditional crank system. The intervention involved 1h training sessions, 5 times per week for 6weeks at a heart rate corresponding to 70% of VO(2peak). VO(2) at 100, 140, 180, 220 and 260 and power output at 4mmolL(-1) blood lactate were determined during an incremental test. VO(2peak) was recorded during a ramp protocol. Mean and peak power output were assessed during a 30s cycle sprint. The maximal voluntary isometric strength of the quadriceps and biceps femoris muscles was obtained using a training machine equipped with a force sensor. No differences were observed between the groups for changes in any variable (P=0.15-0.90; effect size=0.00-0.30). Our results demonstrate that a 6week (30 sessions) training block using decoupled crank systems does not result in changes in any physiological or performance variables in highly trained competitive cyclists.

The Power Profile Predicts Road Cycling MMP

Laboratory tests of fitness variables have previously been shown to be valid predictors of cycling time-trial performance. However, due to the influence of drafting, tactics and the variability of power output in mass-start road races, comparisons between laboratory tests and competition performance are limited. The purpose of this study was to compare the power produced in the laboratory Power Profile (PP) test and Maximum Mean Power (MMP) analysis of competition data. Ten male cyclists (mean+/-SD: 20.8+/-1.5 y, 67.3+/-5.5 kg, V O (2 max) 72.7+/-5.1 mL x kg (-1) x min (-1)) completed a PP test within 14 days of competing in a series of road races. No differences were found between PP results and MMP analysis of competition data for durations of 60-600 s, total work or estimates of critical power and the fixed amount of work that can be completed above critical power (W'). Self-selected cadence was 15+/-7 rpm higher in the lab. These results indicate that the PP test is an ecologically valid assessment of power producing capacity over cycling specific durations. In combination with MMP analysis, this may be a useful tool for quantifying elements of cycling specific performance in competitive cyclists.

Effects of High- vs Low-Cadence Interval Training on Physiology and Performance of Competitive Cyclists

PURPOSE. High-resistance interval training produces substantial gains in sprint and endurance performance when added to the usual training of cyclists in the competitive phase of a season. Here we report the effect of changing the cadence of the intervals on performance and physiology. METHODS: We randomised 18 road cyclists to a low-cadence (60–70 min−1) or high-cadence (110–120 min−1) group for 4–5 wk of training. Both groups replaced part of their usual training with eight 30-min sessions consisting of three sets of explosive single-leg jumps (20 for each leg) alternating with three sets of high-intensity cycling sprints (5x 30 s with 30-s recoveries between repetitions) performed on a training ergometer with resistance set individually to achieve the desired cadence. Saliva samples were collected before and after each training session to assay testosterone concentration. Performance and physiological measures, obtained on a cycle ergometer before and after the intervention, were mean power in a 60-s time trial and the following measures obtained from a continuous incremental test: peak power, maximum oxygen uptake, 4-mM lactate power, fractional utilization of maximum oxygen uptake at 4-mM lactate, and exercise economy. RESULTS: Power output in the interval sets over the training period increased by 11.0% ± 5.4% (mean ± SD) in the low-cadence group and by 8.3% ± 2.1% in the high-cadence group. Testosterone concentration increased in each training session, by 96% ± 25% (mean ± between-session SD) in the low-cadence group and by 62% ± 20% in the high-cadence group. There were substantial enhancements in performance in the low-cadence group (6–11 %) and high-cadence group (2–3%). Mean changes (±90% confidence limits) in the low-cadence group relative to the high-cadence group were: 60-s mean power, 2.5% (±4.8%); peak power, 3.6% (±3.7%); maximum oxygen uptake, 3.2% (±4.2%); 4-mM lactate power, 7.0% (±5.9%); fractional utilization, 0.9% (±4.9%); and exercise economy at 50% and 80% of pre-testpeak power, 5.1% (±4.9%) and 0.2% (±4.1%) respectively. CONCLUSION. Low-cadence interval training is probably more effective than high-cadence training in improving performance of well-trained competitive cyclists. The differences in performance could be due to different effects of the two training cadences on economy and maximum oxygen uptake, possibly mediated in part by training-induced changes in testosterone.

Combining Explosive and High-Resistance Training Improves Performance in Competitive Cyclists

In several recent studies, athletes experienced substantial gains in sprint and endurance performance when explosive training or high-intensity interval training was added in the noncompetitive phase of a season. Here we report the effect of combining these 2 types of training on performance in the competitive phase. We randomized 18 road cyclists to an experimental (n = 9) or control (n = 9) group for 4-5 weeks of training. The experimental group replaced part of their usual training with twelve 30-minute sessions consisting of 3 sets of explosive single-leg jumps (20 for each leg) alternating with 3 sets of high-resistance cycling sprints (5 x 30 seconds at 60-70 min(-1) with 30-second recoveries between repetitions). Performance measures, obtained over 2-3 days on a cycle ergometer before and after the intervention, were mean power in a 1- and 4-km time trial, peak power in an incremental test, and lactate-profile power and oxygen cost determined from 2 fixed submaximal workloads. The control group showed little mean change in performance. Power output sampled in the training sprints of the experimental group indicated a plateau in the training effect after 8-12 sessions. Relative to the control group, the mean changes (+/-90% confidence limits) in the experimental group were: 1-km power, 8.7% (+/-2.5%); 4-km power, 8.1% (+/-4.1%); peak power, 6.8% (+/-3.6); lactate-profile power, 3.7% (+/-4.8%); and oxygen cost, -3.0% (+/-2.6%). Individual responses to the training were apparent only for 4-km and lactate-profile power (standard deviations of 2.5% and 2.8%, respectively). The addition of explosive training and high-resistance interval training to the programs of already well-trained cyclists produces major gains in sprint and endurance performance, partly through improvements in exercise efficiency and anaerobic threshold.

Effects of blood donation on exercise performance in competitive cyclists

This study evaluated 10 male cyclists before and after phlebotomy to determine the effect of donation of 1 U of blood on exercise performance. Each subject underwent maximal exercise testing with oxygen consumption measurement at baseline, 2 hours after phlebotomy, 2 days after phlebotomy, and 7 days after phlebotomy. Maximal performance was decreased for at least 1 week. Submaximal performance was unaffected by blood donation.

High efficiency of type I muscle fibers improves performance.

We have recently demonstrated that people with a high percentage of Type I muscle fibers display a relatively high muscular efficiency when cycling. These individuals generate a relatively high muscular power output at a given steady-state level of oxygen consumption and caloric expenditure. The purpose of this study was to directly determine the extent to which differences in muscle fiber composition and efficiency influence endurance performance in competitive cyclists. The percentage of Type I and II muscle fibers was determined from several biopsies from the vastus lateralis which were histochemically stained for ATPase activity. During a laboratory performance test, 14 endurance trained cyclists (mean +/- SE; VO2max, 5.2 +/- 0.11/min; body weight, 74 +/- 1 kg) cycled an ergometer for 1 h at the highest work rate they could tolerate. VO2 and RER were simultaneously measured using open circuit spirometry for calculating caloric expenditure. Subjects were divided into two groups of seven according to their muscle fiber type composition: High % Type I Group (> 56% Type I fibers); Normal % Type I Group (38-55% Type I fibers). Each subject from High % Type I Group was paired with a subject from the Normal % Type I Group according to their similarity in VO2max, blood lactate threshold and average VO2 maintained during the 1 h performance test. Both groups averaged 4.5 +/- 0.11/min during the 1 h performance test (i.e., 86-88% VO2max).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of diet manipulation on metabolic changes and performance in competitive cyclists

Thirteen highly trained subjects were studied for the effect of consuming a normal carbohydrate‐rich diet (N) on energy exchanged, substrate metabolism and performance. Six of these subjects performed the same protocol receiving N supplemented with a high maltodextrin‐low fructose beverage (Mf). The studies were performed in random order. The subjects performed two days of sustained exhausting cycling, proceeded and followed by a standardized resting day, in a respiration chamber allowing for continuous gas analysis, weighed food and fluid intake, collection of excreta and drawing of blood samples at 07.00 hours, 12.00 hours (halfway exercise) and 15.00 hours at exhaustion. Muscle biopsies were taken prior to, 45 min after and 24 h after exercise (energy expenditure 25.2–26.6 MJ/day).The results showed that while consuming a normal diet, the cyclists develop a negative energy balance (‐9 MJ/day) and regulate their hormone levels in such a way that fat oxidation and protein breakdown are increased and CHO oxidation becomes depressed.When supplemented with Mf the subjects showed increased blood glucose, insulin and decreased glucagon levels. Fat metabolism was significantly depressed as indicated by the levels of blood fatty acids, glycerol and ketones.A significant glycogen sparing, as well as supercompensation within 24 h of recovery, was observed after Mf supplementation. The normal ad libitum available CHO‐rich diet was insufficient fully to restore glycogen within 24 h. The changes in substrate availability and glycogen depletion were accompanied by a significant performance improvement, 126% when cycling a final 90% Wmax bout, when supplemented with Mf compared to N.