Physical demands and power profile of different stage types within a cycling grand tour

Trehalose Improved 20-min Cycling Time-Trial Performance After 100-min Cycling in Amateur Cyclists

Carbohydrate (CHO) supplementation during endurance exercise can improve performance. However, it is unclear whether low glycemic index (GI) CHO leads to differential ergogenic and metabolic effects compared with a standard high GI CHO. This study investigated the ergogenic and metabolic effects of CHO supplementation with distinct GIs, namely, (a) trehalose (30 g/hr), (b) isomaltulose (30 g/hr), (c) maltodextrin (60 g/hr), and (d) placebo (water). In this double-blind, crossover, counterbalanced, placebo-controlled study, 13 male cyclists cycled a total of 100 min at varied exercise intensity (i.e., 10-min stages at 1.5, 2.0, and 2.5 W/kg; repeated three times plus two 5-min stages at 1.0 W/kg before and after the protocol), followed by a 20-min time trial on four separated occasions. Blood glucose and lactate (every 20 min), heart rate, and ratings of perceived exertion were collected throughout, and muscle biopsies were taken before and immediately after exercise. The results showed that trehalose improved time-trial performance compared with placebo (total work done 302 ± 39 vs. 287 ± 48 kJ; p = .01), with no other differences between sessions (all p ≥ .07). Throughout the 100-min protocol, blood glucose was higher with maltodextrin compared with the other supplements at all time points (all p < .05). Heart rate, ratings of perceived exertion, muscle glycogen content, blood glucose, and lactate were not different between conditions when considering the 20-min time trial (all p > .05). Trehalose supplementation throughout endurance exercise improved cycling performance and appears to be an appropriate CHO source for exercise tasks up to 2 hr. No ergogenic superiority between the different types of CHO was established.

The repeated bout effect of traditional resistance training on cycling efficiency and performance

PURPOSE

This study examined the repeated bout effect of two resistance training bouts on cycling efficiency and performance.

METHODS

Ten male resistance-untrained cyclists (age 38 ± 13 years; height 180.4 ± 7.0 cm; weight 80.1 ± 10.1; kg; VO2max 51.0 ± 7.6 ml.kg-1.min-1) undertook two resistance training bouts at six-repetition maximum. Blood creatine kinase (CK), delayed-onset of muscle soreness (DOMS), counter-movement jump (CMJ), squat jump (SJ), submaximal cycling and time-trial performance were examined prior to (Tbase), 24 (T24) and 48 (T48) h post each resistance training bout.

RESULTS

There were significantly lower values for DOMS (p = 0.027) after Bout 2 than Bout 1. No differences were found between bouts for CK, CMJ, SJ and submaximal cycling performance. However, jump height (CMJ and SJ) submaximal cycling measures (ventilation and perceived exertion) were impaired at T24 and T48 compared to Tbase (p < 0.05). Net efficiency during submaximal cycling improved at Bout 2 (23.8 ± 1.2) than Bout 1 (24.3 ± 1.0%). There were no changes in cycling time-trial performance, although segmental differences in cadence were observed between bouts and time (i.e. Tbase vs T24 vs T48; p < 0.05).

CONCLUSION

Cyclists improved their cycling efficiency from Bout 1 to Bout 2 possibly due to the repeated bout effect. However, cyclists maintained their cycling completion times during exercise-induced muscle damage (EIMD) in both resistance training bouts, possibly by altering their cycling strategies. Thus, cyclists should consider EIMD symptomatology after resistance training bouts, particularly for cycling-specific technical sessions, regardless of the repeated bout effect.

The Characteristics of Endurance Events with a Variable Pacing Profile-Time to Embrace the Concept of "Intermittent Endurance Events"?

A variable pacing profile is common in different endurance events. In these races, several factors, such as changes in elevation or race dynamics, lead participants to perform numerous surges in intensity. These surges are so frequent that certain events, such as cross-country (XC) skiing, mountain biking (MTB), triathlon, and road cycling, have been termed "intermittent endurance events". The characteristics of these surges vary depending on the sport: MTB and triathlon require athletes to perform numerous short (<10 s) bouts; XC skiing require periods of short- and moderate-(30 s to 2 min) duration efforts, while road cycling is comprised of a mix of short-, moderate-, and long-duration (>2 min) bouts. These bouts occur at intensities above the maximal metabolic steady state (MMSS), with many efforts performed at intensities above the athletes' maximal aerobic power or speed (MAP/MAS) (i.e., supramaximal intensities). Given the factors that influence the requirement to perform surges in these events, athletes must be prepared to always engage in a race with a highly stochastic pace. The aim of this review is to characterize the variable pacing profile seen in endurance events and to discuss how the performance of multiple maximal and supramaximal surges in intensity can affect how athletes fatigue during a race and influence training strategies that can lead to success in these races.

Effects of In-Exercise Carbohydrate Supplementation on Prolonged High-Intensity Exercise Performance in Oral Contraceptive Users

PURPOSE

To examine the impact of oral contraceptive (OC) phases on performance, physiological, and subjective responses to prolonged, intensive exercise when carbohydrate (CHO) stores are reduced.

METHODS

Ten well-trained female cyclists using monophasic OC completed 4 identical trials (>150 min) under conditions of in-trial 60-g·h-1 CHO supplementation (CHO+) or placebo (CHO-) during the sugar- (SUG) and active-pill (ACT) phases of their OC cycle. Each trial comprised two 400-kcal time trials (TT) separated by 1 hour of submaximal cycling at first ventilatory threshold.

RESULTS

Change in completion time from TT1 to TT2 was minimized in CHO+ compared with CHO- (4.06 [2.55] vs 6.08 [5.33] min; P = .019, effect size = -0.36). An interaction effect of OC and CHO was observed for time to complete TT (P = .006), mean TT power (P = .002), mean TT heart rate (P = .002), and posttrial emotional balance (P = .020) and negative emotional state (P = .033). In ACT, mean TT power and heart rate were higher in CHO+ when compared with CHO-, resulting in faster TTs in CHO+ and improved posttrial emotional well-being. When CHO was not supplemented, TT power and heart rate were higher in SUG when compared with ACT, resulting in faster TTs in SUG and improved posttrial emotional balance.

CONCLUSION

CHO depletion during ACT negatively influenced TT performance and emotional well-being when compared with SUG. Irrespective of OC pill phase, CHO supplementation should be prioritized to sustain performance and improve postexercise recovery-stress balance.

Pro-cycling team cyclist assignment for an upcoming race

Professional bicycle racing is a popular sport that has attracted significant attention in recent years. The evolution and ubiquitous use of sensors allow cyclists to measure many metrics including power, heart rate, speed, cadence, and more in training and racing. In this paper we explore for the first time assignment of a subset of a team's cyclists to an upcoming race. We introduce RaceFit, a model that recommends, based on recent workouts and past assignments, cyclists for participation in an upcoming race. RaceFit consists of binary classifiers that are trained on pairs of a cyclist and a race, described by their relevant properties (features) such as the cyclist's demographic properties, as well as features extracted from his workout data from recent weeks; as well additional properties of the race, such as its distance, elevation gain, and more. Two main approaches are introduced in recommending on each stage in a race and aggregate from it to the race, or on the entire race. The model training is based on binary label which represent participation of cyclist in a race (or in a stage) in past events. We evaluated RaceFit rigorously on a large dataset of three pro-cycling teams' cyclists and race data achieving up to 80% precision@i. The first experiment had shown that using TP or STRAVA data performs the same. Then the best-performing parameters of the framework are using 5 weeks time window, imputation was effective, and the CatBoost classifier performed best. However, the model with any of the parameters performed always better than the baselines, in which the cyclists are assigned based on their popularity in historical data. Additionally, we present the top-ranked predictive features.

Power Profile during Cycling in World Triathlon Series and Olympic Games

This study aimed to analyze the power profile (PP) during the cycling segment of international-level triathletes in the World Triathlon Series (WTS) and Olympics and to evaluate the influence of circuit type, race distance (Sprint or Olympic distance) and race dynamics on the development of the cycling leg and the final race position. Four male triathletes participated in the study. Twenty races were analyzed using geolocation technology and power-meter data to analyze PP, race dynamics, and course characteristics. Before the races, incremental tests of volitional exhaustion with gas analysis were performed to determine power intensity zones. Nonparametric Mann-Whitney U tests and correlation analyses were conducted to identify differences and relationships between various variables. A correlation between the time spent above maximal aerobic power (MAP) and dangerous curves per kilometer (r = 0.46; p < 0.05) and bike split result (BSR) (r = -0.50; p < 0.05) was observed. Also, moderate correlation was found between BSR and the final race position (r = 0.46; p < 0.01). No differences were found between sprint and Olympic distance races in any variable. Power output variability, influenced by technical circuit segments, remains the main characteristic in international short-distance races. The results of the present study suggest that the triathletes who are better adapted to intermittent high intensity efforts perform better cycling legs at international high-level races.

Contemporary blood doping-Performance, mechanism, and detection

Blood doping is prohibited for athletes but has been a well-described practice within endurance sports throughout the years. With improved direct and indirect detection methods, the practice has allegedly moved towards micro-dosing, that is, reducing the blood doping regime amplitude. This narrative review evaluates whether blood doping, specifically recombinant human erythropoietin (rhEpo) treatment and blood transfusions are performance-enhancing, the responsible mechanism as well as detection possibilities with a special emphasis on micro-dosing. In general, studies evaluating micro-doses of blood doping are limited. However, in randomized, double-blinded, placebo-controlled trials, three studies find that infusing as little as 130 ml red blood cells or injecting 9 IU × kg bw-1 rhEpo three times per week for 4 weeks improve endurance performance ~4%-6%. The responsible mechanism for a performance-enhancing effect following rhEpo or blood transfusions appear to be increased O2 -carrying capacity, which is accompanied by an increased muscular O2 extraction and likely increased blood flow to the working muscles, enabling the ability to sustain a higher exercise intensity for a given period. Blood doping in micro-doses challenges indirect detection by the Athlete Biological Passport, albeit it can identify ~20%-60% of the individuals depending on the sample timing. However, novel biomarkers are emerging, and some may provide additive value for detection of micro blood doping such as the immature reticulocytes or the iron regulatory hormones hepcidin and erythroferrone. Future studies should attempt to validate these biomarkers for implementation in real-world anti-doping efforts and continue the biomarker discovery.

Creatine supplementation and endurance performance: surges and sprints to win the race

Creatine supplementation is an effective ergogenic aid to augment resistance training and improve intense, short duration, intermittent performance. The effects on endurance performance are less known. The purpose of this brief narrative review is to discuss the potential mechanisms of how creatine can affect endurance performance, defined as large muscle mass activities that are cyclical in nature and are >~3 min in duration, and to highlight specific nuances within the literature. Mechanistically, creatine supplementation elevates skeletal muscle phosphocreatine (PCr) stores facilitating a greater capacity to rapidly resynthesize ATP and buffer hydrogen ion accumulation. When co-ingested with carbohydrates, creatine enhances glycogen resynthesis and content, an important fuel to support high-intensity aerobic exercise. In addition, creatine lowers inflammation and oxidative stress and has the potential to increase mitochondrial biogenesis. In contrast, creatine supplementation increases body mass, which may offset the potential positive effects, particularly in weight-bearing activities. Overall, creatine supplementation increases time to exhaustion during high-intensity endurance activities, likely due to increasing anaerobic work capacity. In terms of time trial performances, results are mixed; however, creatine supplementation appears to be more effective at improving performances that require multiple surges in intensity and/or during end spurts, which are often key race-defining moments. Given creatines ability to enhance anaerobic work capacity and performance through repeated surges in intensity, creatine supplementation may be beneficial for sports, such as cross-country skiing, mountain biking, cycling, triathlon, and for short-duration events where end-spurts are critical for performance, such as rowing, kayaking, and track cycling.

The proportional distribution of training by elite endurance athletes at different intensities during different phases of the season

The present review examines retrospective analyses of training intensity distribution (TID), i.e., the proportion of training at moderate (Zone 1, Z1), heavy (Z2) and severe (Z3) intensity by elite-to-world-class endurance athletes during different phases of the season. In addition, we discuss potential implications of our findings for research in this field, as well as for training by these athletes. Altogether, we included 175 TIDs, of which 120 quantified exercise intensity on the basis of heart rate and measured time-in-zone or employed variations of the session goal approach, with demarcation of zones of exercise intensity based on physiological parameters. Notably, 49% of the TIDs were single-case studies, predominantly concerning cross-country skiing and/or the biathlon. Eighty-nine TIDs were pyramidal (Z1 > Z2 > Z3), 65 polarized (Z1 > Z3 > Z2) and 8 "threshold" (Z2 > Z1 = Z3). However, these relative numbers varied between sports and the particular phases of the season. In 91% (n = 160) of the TIDs >60% of the endurance exercise was of low intensity. Regardless of the approach to quantification or phase of the season, cyclists and swimmers were found to perform a lower proportion of exercise in Z1 (<72%) and higher proportion in Z2 (>16%) than athletes involved in the triathlon, speed skating, rowing, running, cross-country skiing or biathlon (>80% in Z1 and <12% in Z2 in all these cases). For most of the athletes their proportion of heavy-to-severe exercise was higher during the period of competition than during the preparatory phase, although with considerable variability between sports. In conclusion, the existing literature in this area does not allow general conclusions to be drawn. The methods utilized for quantification vary widely and, moreover, contextual information concerning the mode of exercise, environmental conditions, and biomechanical aspects of the exercise is often lacking. Therefore, we recommend a more comprehensive approach in connection with future investigations on the TIDs of athletes involved in different endurance sports.

Anaerobic Speed Reserve and Performance Relationships Between International and World-Class Short-Track Speed Skating

PURPOSE

Short-track speed skating race distances of 500, 1000, and 1500 m that last ∼40 seconds to ∼2.5 minutes and require a maximal intensity at speeds beyond maximal oxygen uptake (VO2max). Recently, the anaerobic speed reserve (ASR) has been applied by scientists and coaches in middle-distance sports to deepen understanding of 1- to 5-minute event performance where different physiological profiles (speed, hybrid, and endurance) can have success.

METHODS

World-class (women, n = 2; men, n = 3) and international-level (women, n = 4; men, n = 5) short-track speed skaters completed maximal aerobic speed and maximal skating speed tests. ASR characteristics were compared between profiles and associated with on-ice performance.

RESULTS

World-class athletes raced at a lower %ASR in the 1000- (3.1%; large; almost certainly) and 1500-m (1.8%; large; possibly) events than international athletes. Men's and women's speed profiles operated at a higher %ASR in the 500-m than hybrid and endurance profiles, whereas in the 1500-m, endurance profiles worked at a substantially lower %ASR than hybrid and speed profiles. Women's 500-m performance is very largely associated with maximal skating speed, while women's maximal aerobic speed appears to be a key determining factor in the 1000- and 1500-m performance.

CONCLUSION

World-class short-track speed skaters can be developed in speed, hybrid, and endurance profiles but achieve their performance differently by leveraging their strongest characteristics. These results show nuanced differences between men's and women's 500-, 1000- and 1500-m event performance across ASR profile that unlock new insights for individualizing athlete performance in these disciplines.

Acute effects of fatigue on internal and external load variables determining cyclists' power profile

The aim of the present study was to determine whether fatigue affects internal and external load variables determining power profile in cyclists. Ten cyclists performed outdoor power profile tests (lasting 1-, 5 and 20-min) on two consecutive days, subject either to a fatigued condition or not. Fatigue was induced by undertaking an effort (10-min at 95% of average power output obtained in a 20-min effort followed by 1-min maximum effort) until the power output decreased by 20% compared to the 1-min power output. Fatigued condition decreased power output (p < 0.05, 1-min: 9.0 ± 3.8%; 5-min: 5.9 ± 2.5%; 20-min: 4.1 ± 1.9%) and cadence in all test durations, without differences in torque. Lactate decreased in longer efforts when a fatigue protocol had previously been conducted (e.g., 20-min: 8.6 ± 3.0 vs. 10.9 ± 2.7, p < 0.05). Regression models (r² ≥ 0.95, p < 0.001) indicated that a lower variation in load variables of 20-min in fatigued condition compared with the non-fatigued state resulted in a lower decrease in critical power after the fatigue protocol. The results suggest that fatigued condition on power was more evident in shorter efforts and seemed to rely more on a decrease in cadence than on torque.

External and Internal Work Load During a Mountain Time Trial in Trained Handcyclists Versus a World-Class Handcyclist and Determinants of Performance

OBJECTIVES

The aims of the study were to evaluate the external and internal work load of trained handcyclists during a mountain time trial, to compare the results with a world-class handcyclist, and to identify time trial performance determinants.

DESIGN

Ten trained and one world-class handcyclists performed a graded exercise test to determine power output and heart rate at the (first and second) ventilatory thresholds and exhaustion. Power output and heart rate were continuously measured during the race.

RESULTS

The mean absolute power output during the race (119 ± 21 vs. 203 W, P < 0.001) was lower in the trained handcyclists compared with the world-class handcyclist. The absolute and relative heart rate during the race (86 ± 7% vs. 88%, P = 0.40) and relative power output during the race (66 ± 10% vs. 62%, P = 0.24) were similar. Trained handcyclists cycled significantly less time at a power output between first and second ventilatory thresholds (48% vs. 64%, P = 0.02) and more at a power output greater than second ventilatory threshold (34% vs. 11%, P = 0.005). Power output at the second ventilatory threshold showed the strongest correlation with finish time ( r = -0.78) and peak power output with mean power output of the race ( r = 0.90).

CONCLUSIONS

The laboratory outcome peak power output and power output at the second ventilatory threshold are important performance determinants for longer time trials in handcyclists, and it is, therefore, important to improve these outcomes with training. Because the trained handcyclists cycled most of the race in intensity zones 2 and 3, it is recommended to incorporate these zones also in the training.

Modeling the Power-Duration Relationship in Professional Cyclists During the Giro d'Italia

ABSTRACT

Vinetti, G, Pollastri, L, Lanfranconi, F, Bruseghini, P, Taboni, A, and Ferretti, G. Modeling the power-duration relationship in professional cyclists during the Giro d'Italia. J Strength Cond Res 37(4): 866-871, 2023-Multistage road bicycle races allow the assessment of maximal mean power output (MMP) over a wide spectrum of durations. By modeling the resulting power-duration relationship, the critical power ( CP ) and the curvature constant ( W' ) can be calculated and, in the 3-parameter (3-p) model, also the maximal instantaneous power ( P0 ). Our aim is to test the 3-p model for the first time in this context and to compare it with the 2-parameter (2-p) model. A team of 9 male professional cyclists participated in the 2014 Giro d'Italia with a crank-based power meter. The maximal mean power output between 10 seconds and 10 minutes were fitted with 3-p, whereas those between 1 and 10 minutes with the 2- model. The level of significance was set at p < 0.05. 3-p yielded CP 357 ± 29 W, W' 13.3 ± 4.2 kJ, and P0 1,330 ± 251 W with a SEE of 10 ± 5 W, 3.0 ± 1.7 kJ, and 507 ± 528 W, respectively. 2-p yielded a CP and W' slightly higher (+4 ± 2 W) and lower (-2.3 ± 1.1 kJ), respectively ( p < 0.001 for both). Model predictions were within ±10 W of the 20-minute MMP of time-trial stages. In conclusion, during a single multistage racing event, the 3-p model accurately described the power-duration relationship over a wider MMP range without physiologically relevant differences in CP with respect to 2-p, potentially offering a noninvasive tool to evaluate competitive cyclists at the peak of training.

Design and Testing of a Smart Facemask for Respiratory Monitoring during Cycling Exercise

Given the importance of respiratory frequency (f_R) as a valid marker of physical effort, there is a growing interest in developing wearable devices measuring f_R in applied exercise settings. Biosensors measuring chest wall movements are attracting attention as they can be integrated into textiles, but their susceptibility to motion artefacts may limit their use in some sporting activities. Hence, there is a need to exploit sensors with signals minimally affected by motion artefacts. We present the design and testing of a smart facemask embedding a temperature biosensor for f_R monitoring during cycling exercise. After laboratory bench tests, the proposed solution was tested on cyclists during a ramp incremental frequency test (RIFT) and high-intensity interval training (HIIT), both indoors and outdoors. A reference flowmeter was used to validate the f_R extracted from the temperature respiratory signal. The smart facemask showed good performance, both at a breath-by-breath level (MAPE = 2.56% and 1.64% during RIFT and HIIT, respectively) and on 30 s average f_R values (MAPE = 0.37% and 0.23% during RIFT and HIIT, respectively). Both accuracy and precision (MOD ± LOAs) were generally superior to those of other devices validated during exercise. These findings have important implications for exercise testing and management in different populations.

Training Periodization, Intensity Distribution, and Volume in Trained Cyclists: A Systematic Review

A well-planned periodized approach endeavors to allow road cyclists to achieve peak performance when their most important competitions are held.

PURPOSE

To identify the main characteristics of periodization models and physiological parameters of trained road cyclists as described by discernable training intensity distribution (TID), volume, and periodization models.

METHODS

The electronic databases Scopus, PubMed, and Web of Science were searched using a comprehensive list of relevant terms. Studies that investigated the effect of the periodization of training in cyclists and described training load (volume, TID) and periodization details were included in the systematic review.

RESULTS

Seven studies met the inclusion criteria. Block periodization (characterized by employment of highly concentrated training workload phases) ranged between 1- and 8-week blocks of high-, medium-, or low-intensity training. Training volume ranged from 8.75 to 11.68 h·wk-1 and both pyramidal and polarized TID were used. Traditional periodization (characterized by a first period of high-volume/low-intensity training, before reducing volume and increasing the proportion of high-intensity training) was characterized by a cyclic progressive increase in training load, the training volume ranged from 7.5 to 10.76 h·wk-1, and pyramidal TID was used. Block periodization improved maximum oxygen uptake (VO2max), peak aerobic power, lactate, and ventilatory thresholds, while traditional periodization improved VO2max, peak aerobic power, and lactate thresholds. In addition, a day-by-day programming approach improved VO2max and ventilatory thresholds.

CONCLUSIONS

No evidence is currently available favoring a specific periodization model during 8 to 12 weeks in trained road cyclists. However, few studies have examined seasonal impact of different periodization models in a systematic way.

Influence of Torque and Cadence on Power Output Production in Cyclists

PURPOSE

No information is available on the torque/cadence relationship in road cyclists. We aimed to establish whether this relationship differs between cyclists of different performance levels or team roles.

METHODS

Mean maximal power (MMP) output data from 177 riders were obtained from 2012 to 2021 from training and competitions. Cyclists were categorized according to their performance level (world-tour [WT, n = 68], procontinental [PC, n = 63], or under 23 [U23, n = 46]) and team role (time trialists [n = 12], all-rounders [n = 94], climbers [n = 64], or team leaders [n = 7]).

RESULTS

A significant interaction effect was found for absolute and relative MMP (P < .001), with higher values in PC than WT for short (5-60 s) efforts and the opposite trend for longer durations. MMP was also greater in PC than in U23 for short efforts (30-60 s), with WT and PC attaining higher MMP than U23 for longer bouts (5-60 min). A significant interaction effect was found for cadence (P = .007, but with no post hoc differences) and absolute (P = .010) and relative torque (P = .002), with PC and WT showing significantly higher torque (all P < .05) than U23 for 5- to 60-minute efforts, yet with no differences between the former 2 performance levels. No interaction effect between team roles was found for cadence (P = .185) or relative torque (P = .559), but a significant interaction effect was found for absolute torque (P < .001), with all-rounders attaining significantly higher values than climbers for 5-second to 5-minute efforts.

CONCLUSIONS

Differences in MMP between cycling performance levels and rider types are dependent on torque rather than cadence, which might support the role of torque development in performance.

Biophysical characterization of the first ultra-cyclist in the world to break the 1,000 km barrier in 24-h non-stop road cycling: A case report

A plethora of factors determine elite cycling performance. Those include training characteristics, pacing strategy, aerodynamics, nutritional habits, psychological traits, physical fitness level, body mass composition, and contextual features; even the slightest changes in any of these factors can be associated with performance improvement or deterioration. The aim of the present case report is to compare the performances of the same ultra-cyclist in achieving two world records (WR) in 24 h cycling. We have analyzed and compared the distance covered and speed for each WR. The 24 h period was split into four-time intervals (0–6 h; > 6–12 h; > 12–18 h; > 18–24 h), and we compared the differences in the distance covered and speed between the two WRs. For both WRs, a strong negative correlation between distance and speed was confirmed (r = –0.85; r = –0.89, for old and new WR, respectively). Differences in speed (km/h) were shown between the two WRs, with the most significant differences in 12–18 h (Δ = 6.50 km/h). For the covered distance in each block, the most significant differences were observed in the last part of the cycling (Δ = 38.54 km). The cyclist effective surface area (ACd) was 0.25 m² less and 20% more drag in the new WR. Additionally, the mechanical power was 8%, the power to overcome drag was 31%, and the power-weight ratio was 8% higher in the new WR. The mechanical efficiency of the cyclist was 1% higher in the new WR. Finally, the heart rate (HR) presented significant differences for the first 6 h (Old WR: 145.80 ± 5.88 bpm; New WR: 139.45 ± 5.82 bpm) and between the 12 and 18 h time interval (Old WR: 133.19 ± 3.53 bpm; New WR: 137.63 ± 2.80 bpm). The marginal gains concept can explain the performance improvement in the new WR, given that the athlete made some improvements in technical specifications after the old WR.

Increased exogenous but unaltered endogenous carbohydrate oxidation with combined fructose-maltodextrin ingested at 120 g h-1 versus 90 g h-1 at different ratios

Purpose

This study aimed to investigate whether carbohydrate ingestion during 3 h long endurance exercise in highly trained cyclists at a rate of 120 g h⁻¹ in 0.8:1 ratio between fructose and glucose-based carbohydrates would result in higher exogenous and lower endogenous carbohydrate oxidation rates as compared to ingestion of 90 g h⁻¹ in 1:2 ratio, which is the currently recommended approach for exercise of this duration.

Methods

Eleven male participants (V̇O_2peak 62.6 ± 7 mL kg⁻¹ min⁻¹, gas exchange threshold (GET) 270 ± 17 W and Respiratory compensation point 328 ± 32 W) completed the study involving 4 experimental visits consisting of 3 h cycling commencing after an overnight fast at an intensity equivalent to 95% GET. During the trials they received carbohydrates at an average rate of 120 or 90 g h⁻¹ in 0.8:1 or 1:2 fructose-maltodextrin ratio, respectively. Carbohydrates were naturally high or low in ¹³C stable isotopes enabling subsequent calculations of exogenous and endogenous carbohydrate oxidation rates.

Results

Exogenous carbohydrate oxidation rates were higher in the 120 g h⁻¹ condition (120–180 min: 1.51 ± 0.22 g min⁻¹) as compared to the 90 g h⁻¹ condition (1.29 ± 0.16 g min⁻¹; p = 0.026). Endogenous carbohydrate oxidation rates did not differ between conditions (2.15 ± 0.30 and 2.20 ± 0.33 g min⁻¹ for 120 and 90 g h⁻¹ conditions, respectively; p = 0.786).

Conclusions

The results suggest that carbohydrate ingestion at 120 g h⁻¹ in 0.8:1 fructose-maltodextrin ratio as compared with 90 g h⁻¹ in 1:2 ratio offers higher exogenous carbohydrate oxidation rates but no additional sparing of endogenous carbohydrates. Further studies should investigate potential performance effects of such carbohydrate ingestion strategies.

Demands of professional female cycling races: influence race level and race duration (single or multi-day events)

AbstractThis study is governed by two aims: firstly, expanding the meagre knowledge store regarding the demands set by professional female road cycling and, secondly, ascertaining whether these demands vary in relation to different race-levels and race duration (single- or multi-day events). A total of 1 349 female professional road races was analyzed and demands (intensity, load and performance) were determined. Races were classified based on race level (i.e. Women's World Tour [WWT], level.1 and level.2 according to the International Cycling Federation) and race duration (single- or multi-day events). Differences were assessed with a multilevel random intercept model whilst the strength of said differences were indicated by Cohens'd (0-0.19 trivial; 0.20-0.59 small; 0.60-1.1.9 moderate; 1.20-1.99 large; ≥2.00 very large). In general, no moderate differences for load and intensity were noted for the different race levels. This result contrasts with data obtained from male road cycling. Moderate higher 3 and 5 min maximal mean power (MMP) values were noted in the WWT compared to Level.2 races. More substantial differences were found to exist between single- and multi-day races with single-day races presenting small to large higher load and intensity values. In addition, single-day races presented higher MMPs overall durations (5sec - 60 min) although these differences can be rated trivial to small. This study contributes to the limited knowledge store describing demands in professional female cycling. The reported data provide valuable insights which may aid practitioners and/or coaches in preparing female professional cyclists for races.

The Performance-Result Gap in Mixed-Reality Cycling – Evidence From the Virtual Tour de France 2020 on Zwift

Background: Mixed-reality sports are increasingly reaching the highest level of sport, exemplified by the first Virtual Tour de France, held in 2020. In road races, power output data are only sporadically available, which is why the effect of power output on race results is largely unknown. However, in mixed-reality competitions, measuring and comparing the power output data of all participants is a fundamental prerequisite for evaluating the athlete’s performance.

Objective: This study investigates the influence of different power output parameters (absolute and relative peak power output) as well as body mass and height on the results in mixed-reality competitions.

Methods: We scrape data from all six stages of the 2020 Virtual Tour de France of women and men and analyze it using regression analysis. Third-order polynomial regressions are performed as a cubic relationship between power output and competition result can be assumed.

Results: Across all stages, relative power output over the entire distance explains most of the variance in the results, with maximum explanatory power between 77% and 98% for women and between 84% and 99% for men. Thus, power output is the most powerful predictor of success in mixed-reality sports. However, the identified performance-result gap reveals that other determinants have a subordinate role in success. Body mass and height can explain the results only in a few stages. The explanatory power of the determinants considered depends in particular on the stage profile and the progression of the race.

Conclusion: By identifying this performance-result gap that needs to be addressed by considering additional factors like competition strategy or the specific use of equipment, important implications for the future of sports science and mixed-reality sports emerge.

Performance Characteristics of TOP5 Versus NOT-TOP5 Races in Female Professional Cycling

INTRODUCTION

Maximal mean power output (MMP) is commonly used to describe the demands and performances of races in professional male cycling. In the female professional cyclist domain, however, there is limited knowledge regarding MMPs in races. Therefore, this study aimed to describe MMPs in female professional cycling races while investigating differences between TOP5 and NOT-TOP5 races.

METHODS

Race data (N = 1324) were collected from 14 professional female cyclists between 2013 and 2019. Races were categorized as TOP5 or NOT-TOP5. The MMPs were consequently determined over a range of different time frames (5 s to 60 min). To provide these MMPs with additional context, 2 factors were determined: when these MMPs were attained in a race (based on duration and kilojoules spent [kJspent·kg-1]) and these MMPs relative to the cyclist's season's best MMP (MMP%best).

RESULTS

Short-duration power outputs (≤1 min) were higher in TOP5 races compared with NOT-TOP5 races. In addition, the timing (both duration and kJspent·kg-1) of all MMPs was later and after more workload in the race in TOP5 compared with NOT-TOP5 races. In contrast, no difference in MMP%best was noted between TOP5 and NOT-TOP5 races.

CONCLUSIONS

TOP5 races in female cycling are presented with higher short-duration MMPs (≤1 min) when compared with NOT-TOP5 races, and cyclists were able to reach a higher percentage of their seasonal best MMP when they were able to finish TOP5. In addition, these MMPs are performed later and after more kJspent·kg-1 in TOP5 versus NOT-TOP5 races, which confirms the importance of "fatigue resistance" in professional (female) cycling.

Differences in Performance Assessments Conducted Indoors and Outdoors in Professional Cyclists

PURPOSE

The purpose of this study was to assess the relationship between typical performance tests among elite and professional cyclists when conducted indoors and outdoors.

METHODS

Fourteen male cyclists of either UCI (Union Cycliste Internationale) Continental or UCI World Tour level (mean [SD] age 20.9 [2.8] y, mass 68.13 [7.25] kg) were recruited to participate in 4 test sessions (2 indoors and 2 outdoors) within a 14-day period, consisting of maximum mean power testing for durations of 60, 180, 300, and 840 seconds.

RESULTS

Across all maximum mean power test durations, the trimmed mean power was higher outdoors compared with indoor testing (P < .05). Critical power was higher outdoors compared with indoors (+19 W, P = .005), while no difference was observed for the work capacity above critical power. Self-selected cadence was 6 rpm higher indoors versus outdoors for test durations of 60 (P = .038) and 300 seconds (P = .002).

CONCLUSIONS

These findings suggest that maximal power testing in indoor and outdoor settings cannot be used interchangeably. Furthermore, there was substantial individual variation in the difference between indoor and outdoor maximum mean powers across all time durations, further highlighting the difficulty of translating results from indoor testing to outdoor on an individual level in elite populations.

The relationship between training characteristics and durability in professional cyclists across a competitive season

RESULTS

Absolute 5MMP_fatigue, 12MMP_fatigue and relative 12MMP_fatigue were significantly lower in late-season compared with early- and mid-season (p < 0.05). The difference in absolute 12MMP_fresh and 12MMP_fatigue was significantly greater in late than in early- and mid-season.A significant relationship was found between training time below the first ventilatory threshold (Time < VT1) and improvements in absolute and relative 2MMP_fatigue (r = 0.43 p = 0.018 and r = 0.376 p = 0.04 respectively); and between a shift towards a polarised training intensity distribution and improvements in absolute and relative 12MMP_fatigue (r = 0.414p = 0.023 for both) between subsequent periods.

CONCLUSION

There is greater variability in the fatigue power profile across a competitive season than the fresh power profile.

Cross-Sectional Differences in Race Demands Between Junior, Under 23, and Professional Road Cyclists

PURPOSE

To compare the race demands of junior (JUN), under 23 (U23), and professional (PRO) road cyclists.

METHODS

Thirty male cyclists, divided into 3 age-related categories (JUN, n = 10; U23, n = 10; and PRO, n = 10), participated in this study. Race data collected during the 2019 competitive season were retrospectively analyzed for race characteristics, external, and internal competition load.

RESULTS

Higher annual and per race duration, distance, elevation gain, Edward's training impulse, total work, and work per hour were observed in PRO versus U23 and JUN, and U23 versus JUN (P < .01). PRO and U23 recorded higher mean maximal power (RPOs) between 5 and 180 minutes compared with JUN (P < .01). Edward's training impulse per hour was higher in JUN than PRO and U23 (P < .01). Accordingly, JUN spent a higher percentage of racing time in high internal intensity zones compared with U23 and PRO, while these 2 categories spent more time at low internal intensity zones (P < .01).

CONCLUSIONS

JUN races were shorter and included less elevation gain per distance unit compared to U23 and PRO races, but more internally demanding. JUN produced less power output in the moderate-, heavy-, and severe-intensity exercise domains compared with U23 and PRO (RPOs: 5-180 min). U23 and PRO races presented similar work demands per hour and RPOs, but PRO races were longer than U23.

New Horizons in Carbohydrate Research and Application for Endurance Athletes

The importance of carbohydrate as a fuel source for exercise and athletic performance is well established. Equally well developed are dietary carbohydrate intake guidelines for endurance athletes seeking to optimize their performance. This narrative review provides a contemporary perspective on research into the role of, and application of, carbohydrate in the diet of endurance athletes. The review discusses how recommendations could become increasingly refined and what future research would further our understanding of how to optimize dietary carbohydrate intake to positively impact endurance performance. High carbohydrate availability for prolonged intense exercise and competition performance remains a priority. Recent advances have been made on the recommended type and quantity of carbohydrates to be ingested before, during and after intense exercise bouts. Whilst reducing carbohydrate availability around selected exercise bouts to augment metabolic adaptations to training is now widely recommended, a contemporary view of the so-called train-low approach based on the totality of the current evidence suggests limited utility for enhancing performance benefits from training. Nonetheless, such studies have focused importance on periodizing carbohydrate intake based on, among other factors, the goal and demand of training or competition. This calls for a much more personalized approach to carbohydrate recommendations that could be further supported through future research and technological innovation (e.g., continuous glucose monitoring). Despite more than a century of investigations into carbohydrate nutrition, exercise metabolism and endurance performance, there are numerous new important discoveries, both from an applied and mechanistic perspective, on the horizon.

Concurrent Validity of Power From Three On-Water Rowing Instrumentation Systems and a Concept2 Ergometer

Purpose: Instrumentation systems are increasingly used in rowing to measure training intensity and performance but have not been validated for measures of power. In this study, the concurrent validity of Peach PowerLine (six units), Nielsen-Kellerman EmPower (five units), Weba OarPowerMeter (three units), Concept2 model D ergometer (one unit), and a custom-built reference instrumentation system (Reference System; one unit) were investigated.

Methods: Eight female and seven male rowers [age, 21 ± 2.5 years; rowing experience, 7.1 ± 2.6 years, mean ± standard deviation (SD)] performed a 30-s maximal test and a 7 × 4-min incremental test once per week for 5 weeks. Power per stroke was extracted concurrently from the Reference System (via chain force and velocity), the Concept2 itself, Weba (oar shaft-based), and either Peach or EmPower (oarlock-based). Differences from the Reference System in the mean (representing potential error) and the stroke-to-stroke variability (represented by its SD) of power per stroke for each stage and device, and between-unit differences, were estimated using general linear mixed modeling and interpreted using rejection of non-substantial and substantial hypotheses.

Results: Potential error in mean power was decisively substantial for all devices (Concept2, –11 to –15%; Peach, −7.9 to −17%; EmPower, −32 to −48%; and Weba, −7.9 to −16%). Between-unit differences (as SD) in mean power lacked statistical precision but were substantial and consistent across stages (Peach, ∼5%; EmPower, ∼7%; and Weba, ∼2%). Most differences from the Reference System in stroke-to-stroke variability of power were possibly or likely trivial or small for Peach (−3.0 to −16%), and likely or decisively substantial for EmPower (9.7–57%), and mostly decisively substantial for Weba (61–139%) and the Concept2 (−28 to 177%).

Conclusion: Potential negative error in mean power was evident for all devices and units, particularly EmPower. Stroke-to-stroke variation in power showed a lack of measurement sensitivity (apparent smoothing) that was minor for Peach but larger for the Concept2, whereas EmPower and Weba added random error. Peach is therefore recommended for measurement of mean and stroke power.

Power profiling and the power-duration relationship in cycling: a narrative review

Emerging trends in technological innovations, data analysis and practical applications have facilitated the measurement of cycling power output in the field, leading to improvements in training prescription, performance testing and race analysis. This review aimed to critically reflect on power profiling strategies in association with the power-duration relationship in cycling, to provide an updated view for applied researchers and practitioners. The authors elaborate on measuring power output followed by an outline of the methodological approaches to power profiling. Moreover, the deriving a power-duration relationship section presents existing concepts of power-duration models alongside exercise intensity domains. Combining laboratory and field testing discusses how traditional laboratory and field testing can be combined to inform and individualize the power profiling approach. Deriving the parameters of power-duration modelling suggests how these measures can be obtained from laboratory and field testing, including criteria for ensuring a high ecological validity (e.g. rider specialization, race demands). It is recommended that field testing should always be conducted in accordance with pre-established guidelines from the existing literature (e.g. set number of prediction trials, inter-trial recovery, road gradient and data analysis). It is also recommended to avoid single effort prediction trials, such as functional threshold power. Power-duration parameter estimates can be derived from the 2 parameter linear or non-linear critical power model: P(t) = W′/t + CP (W′—work capacity above CP; t—time). Structured field testing should be included to obtain an accurate fingerprint of a cyclist’s power profile.

Power Profile of Top 5 Results in World Tour Cycling Races

PURPOSE

This study evaluated the power profile of a top 5 result achieved in World Tour cycling races of varying types, namely: flat sprint finish, semi-mountain race with a sprint finish, semi-mountain race with uphill finish, and mountain races (MT).

METHODS

Power output data from 33 professional cyclists were collected between 2012 and 2019. This large data set was filtered so that it only included top 5 finishes in World Tour races (18 participants and 177 races). Each of these top 5 finishes were subsequently classified as flat sprint finish, semi-mountain race with uphill finish, semi-mountain race with a sprint finish, and MT based on set criteria. Maximal mean power output (MMP) for a wide range of durations (5 s to 60 min), expressed in both absolute (in Watts) and relative terms (in Watts per kilogram), were assessed for each race type.

RESULT

Short-duration power outputs (<60 s), both in relative and in absolute terms, are of higher importance to be successful in flat sprint finish and semi-mountain race with a sprint finish. Longer-duration power outputs (≥3 min) are of higher importance to be successful in semi-mountain race with uphill finish and MT. In addition, relative power outputs of >10 minutes seem to be a key determining factor for success in MT. These race-type specific MMPs of importance (ie, short-duration MMPs for sprint finishes, longer-duration MMPs for races with more elevation gain) are performed at a wide range (80%-97%) of the cyclist's personal best MMP.

CONCLUSIONS

This study shows that the relative importance of certain points on the power-duration spectrum varies with different race types and provides insight into benchmarks for achieving a result in a World Tour cycling race.

Physical Demands and Performance Indicators in Male Professional Cyclists During a Grand Tour: WorldTour Versus ProTeam Category

PURPOSE

To compare the physical demands and performance indicators of male professional cyclists of 2 different categories (Union Cycliste Internationale WorldTour [WT] and ProTeam [PT]) during a cycling grand tour.

METHODS

A WT team (n = 8, 31.4 [5.4] y) and a PT team (n = 7, 26.9 [3.3] y) that completed "La Vuelta 2020" volunteered to participate. Participants' power output (PO) was registered, and measures of physical demand and physiological performance (kilojoules spent, training stress score, time spent at different PO bands/zones, and mean maximal PO [MMP] for different exertion durations) were computed.

RESULTS

WT achieved a higher final individual position than PT (31 [interquartile range = 33] vs 71 [59], P = .004). WT cyclists showed higher mean PO and kilojoule values than their PT peers and spent more time at high-intensity PO values (>5.25 W·kg-1) and zones (91%-120% of individualized functional threshold power) (Ps < .05). Although no differences were found for MMP values in the overall analysis (P > .05), subanalyses revealed that the between-groups gap increased through the race, with WT cyclists reaching higher MMP values for ≥5-minute efforts in the second and third weeks (Ps < .05).

CONCLUSIONS

Despite the multifactorial nature of cycling performance, WT cyclists spend more time at high intensities and show higher kilojoules and mean PO than their PT referents during a grand tour. Although the highest MMP values attained during the whole race might not differentiate between WT and PT cyclists, the former achieve higher MMP values as the race progresses.

Climbing Performance in U23 and Professional Cyclists during a Multi-stage Race

The aim of this study was to analyze climbing performance across two editions of a professional multistage race, and assess the influence of climb category, prior workload, and intensity measures on climbing performance in U23 and professional cyclists. Nine U23 cyclists (age 20.8±0.9 years) and 8 professional cyclists (28.1±3.2 years) participated in this study. Data were divided into four types: overall race performance, climb category, climbing performance metrics (power output, ascent velocity, speed), and workload and intensity measures. Differences in performance metrics and workload and intensity measures between groups were investigated. Power output, ascent velocity, speed were higher in professionals than U23 cyclists for Cat 1 and Cat 2 (p≤0.001-0.016). Workload and intensity measures (Work_total, Work_total∙km^-1, Elevation_gain, eTRIMP and eTRIMP∙km^-1) were higher in U23 compared to professionals (p=0.002-0.014). Climbing performance metrics were significantly predicted by prior workload and intensity measures for Cat 1 and 2 (R²=0.27-0.89, p≤0.001-0.030) but not Cat 3. These findings reveal that climbing performance in professional road cycling is influenced by climb categorization as well as prior workload and intensity measures. Combined, these findings suggest that Cat 1 and 2 climbing performance could be predicted from workload and intensity measures.

Beta-alanine did not improve high-intensity performance throughout simulated road cycling

This study investigated the effect of beta-alanine supplementation on short-duration sprints and final 4-km simulated uphill cycling time-trial performance during a comprehensive and novel exercise protocol representative of the demands of road-race cycling, and determined if changes were related to increases in muscle carnosine content. Seventeen cyclists (age 38 ± 9 y, height 1.76 ± 0.07 m, body mass 71.4 ± 8.8 kg, V̇O_2max 52.4 ± 8.3 ml·kg^-1·min^-1) participated in this placebo-controlled, double-blind study. Cyclists undertook a prolonged intermittent cycling protocol lasting 125 min, with a 10-s sprint every 20 min, finishing with a 4-km time-trial at 5% simulated incline. Participants completed two familiarization sessions, and two main sessions, one pre-supplementation and one post-supplementation following 28 days of 6.4 g·day^-1 of beta-alanine (N=11) or placebo (N=6; maltodextrin). Muscle biopsies obtained pre- and post-supplementation were analysed for muscle carnosine content. There were no main effects on sprint performance throughout the intermittent cycling test (all P>0.05). There was no group (P=0.69), time (P=0.50) or group x time interaction (P=0.26) on time-to-complete the 4-km time-trial. Time-to-completion did not change from pre- to post-supplementation for BA (-19.2 ± 45.6 s, P=0.43) or PL (+2.8 ± 31.6 s, P=0.99). Beta-alanine supplementation increased muscle carnosine content from pre- to post-supplementation (+9.4 ± 4.0 mmol·kg^-1dm; P<0.0001) but was not related to performance changes (r=0.320, P=0.37). Chronic beta-alanine supplementation increased muscle carnosine content but did not improve short-duration sprint performance throughout simulated road race cycling, nor 4-km uphill time-trial performance conducted at the end of this cycling test.Highlights Performance during prolonged cycling events often depends on the ability to maintain an increased power output during higher intensity periods. Thus, cyclists are likely heavily dependent on their ability to resist fatigue during these periods of high-intensity activity.Meta-analytical data show beta-alanine to be an effective supplement to improve exercise outcomes, but little work exists on its efficacy during dynamic actions that are common during prolonged cycling.Beta-alanine supplementation increased muscle carnosine content but did not generate improvements in the performance of high-intensity cycling (10-s sprints or 4-km uphill time-trial) during a simulated road race cycling protocol.These data suggest that short duration sprints (≤10 s) and longer duration (>10 min) high-intensity activity throughout endurance cycling may not be improved with beta-alanine supplementation despite increases in muscle carnosine content.

The Effect of Cycling-specific Vibration on Neuromuscular Performance

PURPOSE

This study aimed to provide an understanding of how surface-induced vibrations in cycling interfere with short-term neuromuscular performance.

METHODS

The study was conducted as a cross-sectional single cohort trial. Thirty trained cyclists participated (mass = 75.9 ± 8.9 kg, body height = 1.82 ± 0.05 m, V˙O2max = 63 ± 6.8 mL·kg-1⋅min-1). The experimental intervention included a systematic variation of the two independent variables: vibration (Vib: front dropout, 44 Hz, 4.1 mm; rear dropout, 38Hz, 3.5 mm; NoVib) and cranking power (LOW, 137 ± 14 W; MED, 221 ± 18 W; HIGH, 331 ± 65 W) from individual low to submaximal intensity. Dependent variables were transmitted accelerations to the body, muscular activation (gastrocnemius medialis, gastrocnemius lateralis, soleus, vastus lateralis, vastus medialis, rectus femoris, triceps brachii, flexor carpi ulnaris, and lumbar erector spinae), heart rate, and oxygen consumption.

RESULTS

The main findings show that the root-mean-square of local accelerations increased with vibration at the lower extremities, the torso, and the arms-shoulder system. The activation of gastrocnemius medialis, gastrocnemius lateralis, soleus, triceps brachii, and flexor carpi ulnaris increased significantly with vibration. The activation of vastus lateralis increased significantly with vibration only at HIGH cranking power. Oxygen consumption (+2.7%) and heart rate (+5%-7%) increased significantly in the presence of vibration.

CONCLUSIONS

Vibration is a full-body phenomenon. However, the impact of vibration on propulsion is limited as the main propulsive muscles at the thigh are not majorly affected. The demands on the cardiopulmonary and respiratory system increased slightly in the presence of vibration.

The Importance of 'Durability' in the Physiological Profiling of Endurance Athletes

Profiling physiological attributes is an important role for applied exercise physiologists working with endurance athletes. These attributes are typically assessed in well-rested athletes. However, as has been demonstrated in the literature and supported by field data presented here, the attributes measured during routine physiological-profiling assessments are not static, but change over time during prolonged exercise. If not accounted for, shifts in these physiological attributes during prolonged exercise have implications for the accuracy of their use in intensity regulation during prolonged training sessions or competitions, quantifying training adaptations, training-load programming and monitoring, and the prediction of exercise performance. In this review, we argue that current models used in the routine physiological profiling of endurance athletes do not account for these shifts. Therefore, applied exercise physiologists working with endurance athletes would benefit from development of physiological-profiling models that account for shifts in physiological-profiling variables during prolonged exercise and quantify the 'durability' of individual athletes, here defined as the time of onset and magnitude of deterioration in physiological-profiling characteristics over time during prolonged exercise. We propose directions for future research and applied practice that may enable better understanding of athlete durability.

Power Profiling, Workload Characteristics, and Race Performance of U23 and Professional Cyclists During the Multistage Race Tour of the Alps

PURPOSE

The aim of this study was to compare the power profile, internal and external workloads, and racing performance between U23 and professional cyclists and between varying rider types across 2 editions of a professional multistage race.

METHODS

Nine U23 cyclists from a Union Cycliste Internationale "Continental Team" (age 20.8 [0.9] y; body mass 71.2 [6.3] kg) and 8 professional cyclists (28.1 [3.2] y; 63.0 [4.6] kg) participated in this study. Rider types were defined as all-rounders, general classification (GC) riders, and domestiques. Data were collected during 2 editions of a 5-day professional multistage race and split into the following 4 categories: power profile, external and internal workloads, and race performance.

RESULTS

The professional group, including domestiques and GC riders, recorded higher relative power profile values after certain amounts of total work (1000-3000 kJ) than the U23 group or all-rounders (P ≤ .001-.049). No significant differences were found for external workload measures between U23 and professional cyclists, nor among rider types. Internal workloads were higher in U23 cyclists and all-rounders (P ≤ .001-.043) compared with professionals, domestiques, and GC riders, respectively. The power profile significantly predicted percentage general classification and Union Cycliste Internationale points (R2 = .90-.99), whereas external and internal workloads did not.

CONCLUSION

These findings reveal that the power profile represents a practical tool to discriminate between professionals and U23 cyclists as well as rider types. The power profile after 1000 to 3000 kJ of total work could be used by practitioners to evaluate the readiness of U23 cyclists to move into the professional ranks, as well as differentiate between rider types.

Sprint Tactics in the Tour de France: A Case Study of a World-Class Sprinter (Part II)

PURPOSE

To describe the performance and tactical sprint characteristics of a world-class sprinter competing in the Tour de France. In addition, differences in the sprint tactics of 2 teams and won versus lost sprints are highlighted.

METHOD

Power output (PO) and video footage of 21 sprints were analyzed. Position in the peloton and number of teammates supporting the sprinter at different times before the finish line together with PO for different time intervals were determined. Sprints were classified as team Shimano (2013-2014) and team Quick-step (2016-2017), as well as won or lost.

RESULTS

The sprinter was highly successful, winning 14 out of the 21 sprints. At time intervals 10 to 5, 3 to 2, and 1.5 to 1 minute, POs were significantly lower in team Quick-step compared with team Shimano, but the sprinter was positioned further away from the front at 10, 2, 1.5, 1, and 0.5 minutes at team Quick-step compared with team Shimano. The PO was higher at time interval 0.5 to 0.25 minutes before the finish line with team Quick-step when compared with team Shimano. The position of the sprinter in the peloton in lost sprints was further away from the front at 0.5 minutes before the finish compared with won sprints, while no differences were noted for PO and the number of teammates between won and lost sprints.

CONCLUSIONS

Differences in sprint tactics (Shimano vs Quick-step) influence the PO and position in the peloton during the sprint preparation. In addition, the position at 0.5 minutes before the finish line influences the outcome (won or lost) of the sprint.

Demands of the Tour de France: A Case Study of a World-Class Sprinter (Part I)

PURPOSE

To describe the intensity, load, and performance characteristics of a world-class sprinter competing in the Tour de France (TdF).

METHOD

Power output (PO) data were collected from 4 editions of the TdF (2013, 2014, 2016, and 2017) and analyzed. Load, intensity distribution in 5 PO zones, and the maximal mean PO for multiple durations were quantified. Stages were divided in accordance with the 4 different editions of the TdF, as well as the 4 different stage types, that is, flat (FLAT), semimountainous (SMT), mountain (MT), and (team) time trials. In addition, based on their location within the stage, mountain passes were further classified as BEGINNING, MIDDLE, or END of the stage.

RESULTS

No differences in load, intensity, and performance characteristics were found when the 4 editions of the TdF were compared. Time trials were associated with higher intensities but a lower load compared to the other stage types. MT showed higher load and intensity values compared to FLAT and SMT stages. FLAT stages were higher in short maximal mean PO (≤1 min), whereas MT stages showed higher longer endurance maximal mean PO values (≥20 min). In addition, mountain passes situated at the BEGINNING of the stage were completed with a higher PO, cadence, and speed compared with mountain passes situated at the END.

CONCLUSIONS

A world-class sprinter sustains a higher load and spends more time in the high-intensity zones when competing in the TdF than previously reported values suggested. To finish the MT stages as efficiently as possible, sprinters adopt a reverse pacing strategy.

Respiratory impact of a grand tour: insight from professional cycling

PURPOSE

The aim of this study was to evaluate the respiratory function and symptom perception in professional cyclists completing a Grand Tour (GT).

METHODS

Nine male cyclists completed La Vuelta or Tour de France (2018/19). At study entry, airway inflammation was measured via fractional exhaled nitric oxide (FeNO). Respiratory symptoms and pulmonary function were assessed prior to the first stage (Pre-GT), at the second rest day (Mid-GT) and prior to the final stage of the GT (Late-GT). Sniff nasal inspiratory pressure (SNIP) was assessed at pre and late-GT timepoints.

RESULTS

Seven cyclists reported respiratory symptoms during the race (with a prominence of upper airway issues). Symptom severity increased either mid or late-GT for most cyclists. A decline in FEV₁ from pre-to-mid GT (- 0.27 ± 0.24 l, - 5.7%) (P = 0.02) and pre-to-late GT (- 0.27 ± 0.13 l, - 5.7%) (P < 0.001) was observed. Similarly, a decline in FVC (- 0.22 ± 0.17 l, - 3.7%) (P = 0.01) and FEF_25-75 (- 0.49 ± 0.34 l/s, - 11%) (P = 0.02) was observed pre-to-late GT. Overall, eight (89%) and six (67%) demonstrated a clinically meaningful decline (> 200 ml) in FEV₁ and FVC during the GT follow-up, respectively. SNIP remained unchanged pre-to-late GT (n = 5), however, a positive correlation was observed between ΔSNIP and ΔFVC (r = 0.99, P = 0.002).

CONCLUSION

GT competition is associated with a high prevalence of upper respiratory symptoms and a meaningful decline in lung function in professional cyclists. Further research is now required to understand the underpinning physiological mechanisms and determine the impact on overall respiratory health and elite cycling performance and recovery.

Training Characteristics and Power Profile of Professional U23 Cyclists throughout a Competitive Season

BACKGROUND

The purpose of this study was to investigate differences in the power profile derived from training and racing, the training characteristics across a competitive season and the relationships between training and power profile in U23 professional cyclists.

METHODS

Thirty male U23 professional cyclists (age, 20.0 ± 1.0 years; weight, 68.9 ± 6.9 kg; V˙O2max, 73.7 ± 2.5 mL·kg-1·min-1) participated in this study. The cycling season was split into pre-, early-, mid- and late-season periods. Power data 2, 5, 12 min mean maximum power (MMP), critical power (CP) and training characteristics (Hours, Total Work, eTRIMP, Work·h-1, eTRIMP·h-1, TimeVT2) were recorded for each period. Power profiles derived exclusively from either training or racing data and training characteristics were compared between periods. The relationships between the changes in training characteristics and changes in the power profile were also investigated.

RESULTS

The absolute and relative power profiles were higher during racing than training at all periods (p ≤ 0.001-0.020). Training characteristics were significantly different between periods, with the lowest values in pre-season followed by late-season (p ≤ 0.001-0.040). Changes in the power profile between early- and mid-season significantly correlated with the changes in training characteristics (p < 0.05, r = -0.59 to 0.45).

CONCLUSION

These findings reveal that a higher power profile was recorded during racing than training. In addition, training characteristics were lowest in pre-season followed by late-season. Changes in training characteristics correlated with changes in the power profile in early- and mid-season, but not in late-season. Practitioners should consider the influence of racing on the derived power profile and adequately balance training programs throughout a competitive season.

The Physical Demands and Power Profile of Professional Men's Cycling Races: An Updated Review

BACKGROUND

A variety of intensity, load, and performance measures (eg, "power profile") have been used to characterize the demands of professional cycling races with differing stage types. An increased understanding of the characteristics of these races could provide valuable insight for practitioners toward the design of training strategies to optimally prepare for these demands. However, current reviews within this area are outdated and do not include a recent influx of new articles describing the demands of professional cycling races.

PURPOSE

To provide an updated overview of the intensity and load demands and power profile of professional cycling races. Typically adopted measures are introduced and their results summarized.

CONCLUSION

There is a clear trend in the research that stage type significantly influences the intensity, load, and power profile of races with more elevation gain typically resulting in a higher intensity and load and longer-duration power outputs (ie, >10 min). Flat and semimountainous stages are characterized by higher maximal mean power outputs over shorter durations (ie, <2 min). Furthermore, single-day races tend to have a higher (daily) intensity and load compared with stages within multiday races. Nevertheless, while the presented mean (grouped) data provide some indications on the demands of these races and differences between varying competition elements, a limited amount of research is available describing the "race-winning efforts" in these races, and this is proposed as an important area for future research. Finally, practitioners should consider the limitations of each metric individually, and a multivariable approach to analyzing races is advocated.

The effect of road-bike damping on neuromuscular short-term performance

The aim of this study was to understand if and how surface-induced vibrations and road bike damping affect short-term neuromuscular performance in cycling. Thirty cyclists (mass 75.9 ± 8.9 kg, height 1.82 ± 0.05 m, Vo2max 63.0 ± 6.8 ml/min/kg) performed steady-state and maximum effort tests with and without vibration exposure (front dropout: 44 Hz, 4.1 mm; rear dropout: 38 Hz, 3.5 mm) on a damped and a nondamped bike. Transmitted accelerations to the musculoskeletal system, activation of lower extremity muscles (gast. med., soleus, vast. med., rec. fem.) and upper body muscles (erec. spinae, deltoideus, tric. brachii), oxygen uptake, heart rate and crank power output were measured. The main findings indicate a transmission of vibration to the whole body, but since no major propulsive muscles increase their activation with vibration, the systemic energy demand increases only marginally with vibration. Damping reduces vibrations at the upper body, which indicates an increase in comfort, but has no effect on the vibration transfer to the lower extremities. Therefore, road bike damping does not affect neuromuscular response of the propulsive muscle groups and energy demand. Consequently, short-term power output does not increase with damping.

Testing traditions in cycling: newspapers are effective thermal insulators during simulated downhill cycling

BACKGROUND

Cycling downhill accelerates heat loss and requires lower work rates leading to cold discomfort. Historically, cyclists have behaviorally thermoregulated prior to cycling downhill by inserting newspapers into their jerseys. Yet, there is no experimental data to support such a method showing improvements in thermal perception and profile; we hypothesized it would.

METHODS

Two cohorts (N.=8 each) of male participants completed two main trials each involving 30-minutes simulated uphill cycling (65% VO<inf>2peak</inf> 188 [41] W; no fan) followed by 15-minutes downhill cycling (35% VO<inf>2peak</inf> 41 [12] W) in front of an industrial fan (wind speed: 4.6 [0.1] m·s^-1). In one trial participants inserted one (study 1) or two (study 2) tabloid newspapers into their jerseys (PAPER) prior to downhill cycling; the other was a control (NOPAPER). Whole body and torso thermal sensation (TS) and comfort (TC), aural temperature (T<inf>au</inf>), skin temperature (T<inf>skin</inf>), and newspaper mass change (∆) were measured. Data were compared using ANOVA and t-test to 0.05 alpha level.

RESULTS

After uphill cycling thermal and perceptual profiles were similar. In study 1, only TC was transiently improved 1-minute after newspaper insertion. In study 2, T<inf>skin</inf> rate of decline was lower in the PAPER condition (-0.11 [0.12] °C.min^-1 cf -0.53 [0.16] °C.min^-1; P=0.001) and T<inf>chest</inf> remained higher (28.83 [3.17] °C cf 24.39 [3.22] °C). This improved TS but not TC. Newspaper mass increased indicating impaired sweat evaporation (∆<inf>mass</inf>: 5.7 [4.9] g; P=0.01).

CONCLUSIONS

Thermal perception and profile during downhill cycling was improved by inserting two newspapers but not one newspaper into the jersey, supporting our hypothesis.

Demands of professional cycling races: Influence of race category and result

This study analyses the influence of race category and result on the demands of professional cycling races. In total, 2920 race files were collected from 20 male professional cyclists, within a variety of race categories: Single-day (1.WT) and multi-day (2.WT) World Tour races, single-day (1.HC) and multi-day (2.HC) Hors Catégorie races and single-day (1.1) and multi-day (2.1) category 1 races. Additionally, the five cycling "monuments" were analysed separately. Maximal mean power outputs (MMP) were measured across a broad range of durations. Volume and load were large to very largely (d = 1.30-4.80) higher in monuments compared to other single-day race categories. Trivial to small differences were observed for most intensity measures between different single-day race categories, with only RPE and sRPE·km^-1 being moderately (d = 0.70-1.50) higher in the monuments. Distance and duration were small to moderately (d = 0.20-0.80) higher in 2.WT races compared to 2.HC and 2.1 multi-day race categories with only small differences in terms of load and intensity. Generally, higher ranked races (i.e. Monuments, 2.WT and GT) tend to present with lower shorter-duration MMPs (e.g. 5-120 sec) compared to races of "lower rank" (with less differences and/or mixed results being present over longer durations), potentially caused by a "blunting" effect of the higher race duration and load of higher ranked races on short duration MMPs. MMP were small to largely higher over shorter durations (<5 min) for a top-10 result compared to no top-10, within the same category.

Power Assessment in Road Cycling: A Narrative Review

Nowadays, the evaluation of physiological characteristics and training load quantification in road cycling is frequently performed through power meter data analyses, but the scientific evidence behind this tool is scarce and often contradictory. The aim of this paper is to review the literature related to power profiling, functional threshold testing, and performance assessment based on power meter data. A literature search was conducted following preferred reporting items for review statement (PRISMA) on the topic of {“cyclist” OR “cycling” AND “functional threshold” OR “power meter”}. The reviewed evidence provided important insights regarding power meter-based training: (a) functional threshold testing is closely related to laboratory markers of steady state; (b) the 20-min protocol represents the most researched option for functional threshold testing, although shorter durations may be used if verified on an individual basis; (c) power profiling obtained through the recovery of recorded power outputs allows the categorization and assessment of the cyclist’s fitness level; and (d) power meters represent an alternative to laboratory tests for the assessment of the relationship between power output and cadence. This review elucidates the increasing amount of studies related to power profiling, functional threshold testing, and performance assessment based on power meter data, highlighting the opportunity for the expanding knowledge that power meters have brought in the road cycling field.

Training Characteristics of Male and Female Professional Road Cyclists: A 4-Year Retrospective Analysis

PURPOSE

To describe the training intensity and load characteristics of professional cyclists using a 4-year retrospective analysis. Particularly, this study aimed to describe the differences in training characteristics between men and women professional cyclists.

METHOD

For 4 consecutive years, training data were collected from 20 male and 10 female professional cyclists. From those training sessions, heart rate, rating of perceived exertion, and power output (PO) were analyzed. Training intensity distribution as time spent in different heart rate and PO zones was quantified. Training load was calculated using different metrics such as Training Stress Score, training impulse, and session rating of perceived exertion. Standardized effect size is reported as Cohen's d.

RESULTS

Small to large higher values were observed for distance, duration, kilojoules spent, and (relative) mean PO in men's training (d = 0.44-1.98). Furthermore, men spent more time in low-intensity zones (ie, zones 1 and 2) compared with women. Trivial differences in training load (ie, Training Stress Score and training impulse) were observed between men's and women's training (d = 0.07-0.12). However, load values expressed per kilometer were moderately (d = 0.67-0.76) higher in women compared with men's training.

CONCLUSIONS

Substantial differences in training characteristics exist between male and female professional cyclists. Particularly, it seems that female professional cyclists compensate their lower training volume, with a higher training intensity, in comparison with male professional cyclists.

Effects of a low-carbohydrate diet on performance and body composition in trained cyclists

Introduction

Previous evidence suggests that low-carbohydrate diets may improve body composition and performance relative to body weight in endurance athletes. This has been the first study that has attempted to evaluate the utility of low-carbohydrate diets in a sample of eleven trained and experienced road cyclists who consumed 10% of their caloric intake in the form of carbohydrates during four weeks while maintaining a neutral energy balance (50 kcal/kg/day). Body composition was evaluated through an electrical impedance assessment before and after the intervention while maximal power output (5 and 20 min) was measured on a bike trainer by following a standardized protocol and in the same room conditions for all the participants. The study was performed during the preseason, when the subjects could abstain from performing high-intensity workouts. The participants, eleven men aged 31 ± 5 years, performed four weekly 150 min training sessions at submaximal intensities and received nutritional support from a certified sport nutritionist. The intervention resulted in reduced total weight (-2.51 kg) and body fat percentage (2.42%), and improved relative power (+0.2 w/kg for 20 min and +0.25 w/kg for 5 min) values while absolute power remained unchanged. The results suggest that low-carbohydrate diets could be used in order to induce changes in body composition and improve relative power during the preseason. However, future research with larger sample sizes and a control group is needed in order to validate the results.

Physiological demands and characteristics of the participants in a cycling sportive event

BACKGROUND

Cycling sportives have become increasingly popular in the last years. With over 11,000 participants, the Quebrantahuesos (Qh), is one of the most prominent cycling events in Europe and its ever-growing competitive nature has increased the physiological demands required to obtain a great result. The objectives of the current study were to determine the relationship between the power profile and the result in the event as well as to describe the physiological differences among subgroups of participants according to their result.

METHODS

Ninety-one male cyclists took part in the study. Data regarding weight, height, experience and training volume were collected before the event. The raw data from the power meter used by the participants during the event's four climbs was sent to the researchers as an Excel file. Participants were then divided in three different groups according to their performance. One-way analysis of variance was performed to assess differences between groups. Pearson's product-moment correlation coefficient was used to assess for associations among performance and/or anthropometric data.

RESULTS

Group differences were found in body weight (P<0.001), body mass index (P<0.001), training volume (P<0.001) and previous participations in the event (P<0.001). A very high negative correlation between relative power during the climbs and the final time was also observed (r>-0.92; P<0.001).

CONCLUSIONS

Better performances were associated to lower body weight and body mass index and higher training volume, relative power and experience. The current study provides data that suggest that as long as the average relative power is sustained, the pacing strategy throughout the different climbs does not affect the race outcome. This information could be used by cyclists and coaches when preparing the pacing strategy for the event.