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1.
J Strength Cond Res ; 37(5): 1131-1134, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607237

RESUMO

ABSTRACT: Muriel, X, Hernández-Belmonte, A, Mateo-March, M, Valenzuela, PL, Zabala, M, Barranco-Gil, D, Lucia, A, and Pallares, JG. Is the record power profile repeatable? A practical analysis and interpretation in professional cyclists. J Strength Cond Res 37(5): 1131-1134, 2023-This study assessed the repeatability of the Record Power Profile (RPP, i.e., the highest power output that a cyclist can attain for different effort durations under field-based conditions). We registered the RPP of 12 professional cyclists (age 32 ± 5 years) for efforts lasting between 30 seconds and 60 minutes during 3 periods of a season, each of 23-day duration: preparation (including training data only), specific (training and competition data), and competition (competition data only) periods. Repeatability was assessed using the highest 2 (RPP 2 ), 3 (RPP 3 ), and 5 (RPP 5 ) values of mean maximum power obtained by the cyclists for each effort duration in each of the 3 periods. Smaller standard errors of measurement ( SEM ) were found as the competitive period approached, especially for short-duration efforts (i.e., 30 seconds, 1 minute, and 5 minutes, where SEM ranged from 4.3 to 12.5%, 4.1-8.5%, and 2.6-7.0% in the preparation, specific, and competition periods, respectively). However, similar SEM values were found in the 3 periods for RPP 2 , RPP 3 , or RPP 5. In conclusion, the RPP appears as a repeatable parameter for monitoring field-based performance within the different phases of the season in professional cyclists.


Assuntos
Desempenho Atlético , Humanos , Adulto , Ciclismo , Fatores de Tempo , Estações do Ano
2.
Scand J Med Sci Sports ; 32(12): 1738-1746, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35686390

RESUMO

The aim of this study was to describe individual training strategies in preparation to Giro d'Italia of three world class road cyclists who achieved a top 5 in the general classification. Day-to-day power meter training and racing data of three road cyclists (age: 26, 27, 25 years; relative maximum oxygen consumption: 81, 82, 80 ml·min-1 ·kg-1 ; relative 20-min record power output: 6.6, 6.6, 6.4 W kg-1 ) of the 22 weeks (December-May) leading up to the top 5 in Giro d'Italia general classification were retrospectively analyzed. Weekly volume and intensity distribution were considered. Cyclists completed 17, 22, 29 races, trained averagely for 19.7 (7.9), 16.2 (7.0), 14.7 (6.2) hours per week, with a training intensity distribution of 91.3-6.5-2.2, 83.6-10.6-5.8, 86.7-8.9-4.4 in zone 1-zone 2-zone 3 before the Giro d'Italia. Two cyclists spent 55 and 39 days at altitude, one did not attend any altitude camp. Cyclists adopted an overall pyramidal intensity distribution with a relevant increase in high-intensity volume and polarization index in races weeks. Tapering phases seem to be dictated by race schedule instead of literature prescription, with no strength training performed by the three cyclists throughout the entire periodization.


Assuntos
Altitude , Ciclismo , Humanos , Estudos Retrospectivos , Resistência Física
3.
Int J Sports Med ; 43(8): 721-728, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35021246

RESUMO

The use of near-infrared spectroscopy could be an interesting alternative to other invasive or expensive methods to estimate the second lactate threshold. Our objective was to compare the intensities of the muscle oxygen saturation breakpoint obtained with the Humon Hex and the second lactate threshold in elite cyclists. Ninety cyclists performed a maximal graded exercise test. Blood capillary lactate was obtained at the end of steps and muscle oxygenation was continuously monitored. There were no differences (p>0.05) between muscle oxygen oxygenation breakpoint and second lactate threshold neither in power nor in heart rate, nor when these values were relativized as a percentage of maximal aerobic power or maximum heart rate. There were also no differences when men and women were studied separately. Both methods showed a highly correlation in power (r=0.914), percentage of maximal aerobic power (r=0.752), heart rate (r=0.955), and percentage of maximum heart rate (r=0.903). Bland-Altman resulted in a mean difference of 0.05±0.27 W·kg-1, 0.91±4.93%, 0.63±3.25 bpm, and 0.32±1.69% for power, percentage of maximal aerobic power, heart rate and percentage of maximum heart rate respectively. These findings suggest that Humon may be a non-invasive and low-cost alternative to estimate the second lactate threshold intensity in elite cyclists.


Assuntos
Limiar Anaeróbio , Ácido Láctico , Limiar Anaeróbio/fisiologia , Ciclismo/fisiologia , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho
4.
Int J Sports Med ; 43(10): 875-880, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35439835

RESUMO

A new method to monitor internal training load from muscle oxygen saturation using near-infrared spectroscopy could be of practical application for research and training purposes. This technology has been validated in different scientific fields, including sports science, and Humon Hex and Moxy are two leading brands. However, its relationship with hemoglobin has not been studied. Forty-eight professional cyclists, 19 men and 29 women, underwent a blood test to measure hemoglobin in the early morning. Immediately afterwards, hemoglobin and muscle oxygenation were monitored at rest by Moxy and Humon Hex on their right quadriceps (where the skinfold was measured). Venous blood hemoglobin was higher than the measurement for both devices (p<0.001). Both hemoglobin (p<0.001) and muscle oxygen saturation measurements (p<0.05) were higher in Humon Hex than for Moxy, and there was a reasonable reproducibility (ICC=0.35 for hemoglobin and 0.26 for muscle oxygen saturation). Skinfold had an inverse relationship with hemoglobin measurement (r=-0.85 p<0.001 for Humon Hex and r=-0.75 p<0.001 for Moxy). These findings suggest that resting hemoglobin data provided by these devices are not coincident with those of blood sample, and skinfold has an inverse relationship with blood hemoglobin measurement.


Assuntos
Consumo de Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho , Feminino , Hemoglobinas , Humanos , Masculino , Oxigênio , Consumo de Oxigênio/fisiologia , Reprodutibilidade dos Testes , Espectroscopia de Luz Próxima ao Infravermelho/métodos
5.
J Sports Sci ; 40(21): 2461-2467, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36573934

RESUMO

In Bicycle Motocross (BMX) performance is determined by the riders' sprint ability and power output. Therefore, descriptive and predictive performance assessments through laboratory and field tests are of interest. Twelve members of the Spanish BMX National Team performed 4 laboratory tests, including 1RM in squat, a Wingate test, a 5x6-s repeated sprint test (RST) and a force-velocity profile test. These tests were compared with the riders' field performance using the best lap of a simulated BMX competition consisting of 6 all-out laps on a standard BMX track. Pearson's correlation and linear regression analysis showed a significant association (p < 0.05) between the riders' field performance and the 1RM (r = 0.84; R2 = 0.65), the peak power output in the RST (r = 0.87; R2 = 0.78) and the peak power, the mean power and the lactate production in the Wingate test (r = 0.68-0.77; R2 = 0.14-0.65), as well as maximal power from the force-velocity profile (r = 0.71; R2 = 0.53). The laboratory tests included in this study can show information about BMX riders' performance, with the highest values for the peak power obtained in the repeated sprint test (78% of the variance in common).


Assuntos
Desempenho Atlético , Ciclismo , Humanos , Postura , Ácido Láctico , Gravitação , Proteínas Tirosina Quinases
6.
Br J Sports Med ; 55(22): 1262-1269, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33980546

RESUMO

In 2020, the IOC released a consensus statement that provides overall guidelines for the recording and reporting of epidemiological data on injury and illness in sport. Some aspects of this statement need to be further specified on a sport-by-sport basis. To extend the IOC consensus statement on methods for recording and reporting of epidemiological data on injury and illness in sports and to meet the sport-specific requirements of all cycling disciplines regulated by the Union Cycliste Internationale (UCI). A panel of 20 experts, all with experience in cycling or cycling medicine, participated in the drafting of this cycling-specific extension of the IOC consensus statement. In preparation, panel members were sent the IOC consensus statement, the first draft of this manuscript and a list of topics to be discussed. The expert panel met in July 2020 for a 1-day video conference to discuss the manuscript and specific topics. The final manuscript was developed in an iterative process involving all panel members. This paper extends the IOC consensus statement to provide cycling-specific recommendations on health problem definitions, mode of onset, injury mechanisms and circumstances, diagnosis classifications, exposure, study population characteristics and data collection methods. Recommendations apply to all UCI cycling disciplines, for both able-bodied cyclists and para-cyclists. The recommendations presented in this consensus statement will improve the consistency and accuracy of future epidemiological studies of injury and illness in cycling.


Assuntos
Traumatismos em Atletas , Medicina Esportiva , Esportes , Traumatismos em Atletas/epidemiologia , Consenso , Estudos Epidemiológicos , Humanos
7.
Sensors (Basel) ; 21(16)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34450939

RESUMO

Altitude training is a common strategy to improve performance in endurance athletes. In this context, the monitoring of training and the athletes' response is essential to ensure positive adaptations. Heart rate variability (HRV) has been proposed as a tool to evaluate stress and the response to training. In this regard, many smartphone applications have emerged allowing a wide access to recording HRV easily. The purpose of this study was to describe the changes of HRV using a validated smartphone application before (Pre-TC), during (TC), and after (Post-TC) an altitude training camp in female professional cyclists. Training load (TL) and vagal markers of heart rate variability (LnRMSSD, LnRMSSDcv) of seven professional female cyclists before, during, and after and altitude training camp were monitored. Training volume (SMD = 0.80), LnRMSSD (SMD = 1.06), and LnRMSSDcv (SMD = -0.98) showed moderate changes from Pre-TC to TC. Training volume (SMD = 0.74), TL (SMD = 0.75), LnRMSSD (SMD = -1.11) and LnRMSSDcv (SMD = 0.83) showed moderate changes from TC to Post-TC. Individual analysis showed that heart rate variability responded differently among subjects. The use of a smartphone application to measure HRV is a useful tool to evaluate the individual response to training in female cyclists.


Assuntos
Altitude , Smartphone , Adaptação Fisiológica , Atletas , Feminino , Frequência Cardíaca , Humanos
8.
Int J Sports Med ; 38(9): 666-674, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28704881

RESUMO

To analyze cardiovascular and autonomic responses in elite youngsters, 13 male cyclists (15.43±0.51 years) performed a graded-test until voluntary exhaustion. Oxygen consumption (VO2), blood lactate (BLa), arterial oxygen saturation (SaO2), respiratory exchange ratio (RER) and rating of perceived exertion (RPE) were collected, while heart rate (HR) was registered for heart rate variability (HRV) analyses, looking for linear and nonlinear comparisons. Cyclists reached maximal exertion [RPE: 19.14±0.94; BLa: 8.92±2.51 mmol.L-1; RER: 1.04±0.03; SaO2: 92.43±2.5%] and high-level performance (4.41±0.46 W·Kg-1; 60.77±6.87 ml·Kg·min-1) once over 95% of age-predicted HRmax. VO2 and RPE increased, and RR intervals (RRi) decreased (p<0.005), whereas only the short-term scaling exponent of the Detrended Fluctuation Analysis technique (DFA1) displayed similar adaptive changes regarding intensity (p=0.011). After controlling for W·Kg-1 and RRi, DFA1100% (0.260±0.084) showed large-negative correlations with VO2max (r=-0.83; p<0.05) and RPEmax (r=-0.79; p<0.05), suggesting a strong association between the reduction in self-similar properties of the cardiac signal and the capacity to elicit at maximum in youths. Overall-HRV (lnRMSSD) and short-term variability (lnSD1) did not show any association at maximum, or significant differences regarding intensity. DFA1 might reflect ANS-CNS linkage related to cardiac respiratory controls through exercise, becoming a complementary criterion for VO2max testing in youths.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Ciclismo/fisiologia , Teste de Esforço , Frequência Cardíaca , Consumo de Oxigênio , Adolescente , Atletas , Humanos , Masculino
9.
J Sports Sci Med ; 13(1): 97-104, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24570612

RESUMO

Maximising power output during the initial acceleration phase of a bicycle motocross (BMX) race increases the chance to lead the group for the rest of the race. The purpose of this study was to investigate the effect of non-circular chainrings (Q-ring) on performance during the initial acceleration phase of a BMX race. Sixteen male cyclists (Spanish National BMX team) performed two counterbalanced and randomized initial sprints (3.95s), using Q- ring vs. circular chainring, on a BMX track. The sample was divided into two different groups according to their performance (Elite; n = 8 vs. Cadet; n = 8). Elite group covered a greater distance using Q-ring (+0.26 m, p = 0.02; D = 0.23), whilst the improvement for the Cadet (+0.04 m) was not significant (p = 0.87; D = -0.02). Also, there was no significant difference in power output for the Elite group, while the Cadet group revealed larger peak power with the circular chainring. Neither lactate level, nor heart rate showed significant differences due to the different chainring used. The non-circular chainring improved the initial acceleration capacity only in the Elite riders. Key PointsThis work provides novel results demonstrating very significant improvements in the sprint performance of BMX cycling discipline using a non-circular chainring system.This study seeks a practical application from scientific analysisAll data are obtained in a real context of high competition using a sample comprised by the National Spanish Team.Some variables influencing performance as subjects' physical fitness are discussed.Technical equipment approved by International Cycling Union is studied to check its potentially beneficial influence on performance.

10.
Front Sports Act Living ; 6: 1369435, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38752212

RESUMO

In the pursuit of optimal recovery, the significance of sleep cannot be overstated for elite cyclists, including high-level cyclists within the junior category. This study aims to assess the sleep quality of elite athletes of different categories and disciplines, including junior. The sleep quality of 112 high-level cyclists (males n = 80; females n = 32) participating in endurance and sprint disciplines was evaluated using the Pittsburgh Sleep Quality Index (PSQI). A noteworthy 41% of both elite and junior cyclists displayed poor sleep quality. No significant differences were observed between elite and junior cyclists in terms of sleep quality, but there was a medium effect size, indicating greater sleep efficiency in junior cyclists [0.36 (0.16, 0.53)]. Gender differences were found, with females exhibiting worse PSQI scores (males = 4.00 [2.25]; females 5.00 [3.00]; p = 0.035). Endurance cyclists spent more time in bed compared to cyclists from sprinting disciplines (8:30 [1.00] and 8:00 [1:03], respectively; p = 0.019). These findings reveal poor sleep habits, even among individuals classified as good sleepers by the PSQI, emphasizing the importance of preventing sleep disorders in cyclists. This study provides valuable insights into athlete sleep quality, encompassing various categories, genders, and cycling disciplines. In conclusion, elite cyclists demonstrate suboptimal sleep quality, suggesting the potential for interventions utilizing the PSQI. These findings advocate for the incorporation of sleep quality assessments into routine evaluations for athletes.

11.
Int J Sports Physiol Perform ; 19(5): 505-509, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335950

RESUMO

PURPOSE: The aim of this study was to describe the day-by-day training and racing characteristics in preparation for the Giro d'Italia of 1 world-class road cyclist who achieved a place on the podium in the final general classification of the Giro d'Italia. METHODS: Day-by-day power meter training and racing data of 1 study subject (road cyclist; age 25 y; relative maximum oxygen consumption 81 mL·min-1·kg-1; relative 20-min record power output 6.6 W·kg-1) covering the 152 days leading up to the podium in the Giro d'Italia final general classification were retrospectively analyzed. Daily load, daily volume, and intensity distribution were considered. RESULTS: During training a pattern alternating "hard days" versus "easy days" was observed, as significant amounts of medium or high intensity, or load, were not performed for more than 2 consecutive days This pattern was achieved combining high volume (>4 h) with a significant amount of medium and high intensity within the same training sessions. During training, when training load and intensity increased, the density of "easy days" augmented. In 1-week stage races and the Giro d'Italia, 3 to 8 consecutive days with significant amounts of medium and high intensity were performed. A high number of training sessions with small amounts of medium- and high-intensity volume was observed: 38 days accumulating 3 to 10 minutes at medium intensity and 29 days spending 1 to 9 minutes at high intensity. CONCLUSION: These data provide novel insights about the day-by-day periodization strategies leading to a top 3 in the Giro d'Italia general classification.


Assuntos
Ciclismo , Consumo de Oxigênio , Condicionamento Físico Humano , Humanos , Ciclismo/fisiologia , Adulto , Condicionamento Físico Humano/métodos , Estudos Retrospectivos , Masculino , Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Fatores de Tempo
12.
J Sci Med Sport ; 27(6): 430-434, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604818

RESUMO

OBJECTIVES: Although the ability to attenuate power output (PO) declines after accumulated work (i.e., 'durability') is increasingly recognized as a major determinant of cycling performance, the potential role of the intensity of the previous work is unclear. We assessed the effect of work-matched levels of accumulated work at different intensities on performance in male professional cyclists. DESIGN: Observational field-based study. METHODS: PO data was registered in 17 cyclists during a competition season, and the critical power (CP) was repeatedly determined every 4 weeks from training sessions and competitions. Participants' maximum mean power (MMP) for different durations (5 s, 5 min, 10 min, and 20 min) and the CP were determined under 'fresh' conditions (0 kJ·kg-1) and after varying levels of accumulated work (2.5, 5.0 and 7.5 kJ·kg-1) at intensities below and above the CP. RESULTS: A significant decline was found for all MMP values following all levels of accumulated work above the CP (-4.0 %, -1.7 %, -1.8 %, and -3.2 % for 30s, 5 min, 10 min and 20 min-MMP, respectively; all p < 0.001), versus no change after any level of accumulated work below the CP (all p > 0.05). Similar results were observed for the CP, which decreased after all levels of accumulated work above (-2.2 %, -6.1 %, and -16.2 %, after 2.5, 5.0 and 7.5 kJ·kg-1, p < 0.001) but not below this indicator (p > 0.05). CONCLUSIONS: In male professional cyclists, accumulated work above the CP impairs performance compared with work-matched, albeit less intense efforts. This raises concerns on the use of mechanical work per se as a single fatigue/stress indicator in these athletes.


Assuntos
Desempenho Atlético , Ciclismo , Humanos , Masculino , Ciclismo/fisiologia , Desempenho Atlético/fisiologia , Adulto , Adulto Jovem , Esforço Físico/fisiologia
13.
Int J Sports Physiol Perform ; 19(6): 545-549, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38531349

RESUMO

BACKGROUND: Durability (ie, the ability to attenuate the decline in performance after accumulated work) has been identified as a performance determinant in elite cyclists. The aim of the present study was to compare durability in elite cyclists of various performance levels, particularly after high-intensity work, referred to as "high-intensity durability." METHODS: Forty-nine (N = 49) male road cyclists were categorized as either under 23 years of age (U23) (N = 11), Pro Team (N = 13), or World Tour (N = 24). The participants' critical power (CP) was assessed during the preseason. Thereafter, the participants' maximum mean power (MMP) values were determined for efforts of different durations (from 5 s to 30 min) after different levels of accumulated work above CP (from 0 to 7.5 kJ·kg-1). RESULTS: U23 cyclists showed a significant reduction of all relative MMP values for durations ≥1 minute after ≥5 kJ·kg-1 above CP compared with the "fresh" state (0 kJ·kg-1), whereas in Pro Team and World Tour cyclists, a significant reduction was not observed until 7.5 kJ·kg-1 above CP. In the "fresh" state, both Pro Team and particularly World Tour cyclists attained higher MMP values for efforts ≥10 minutes than U23 riders. However, more differences emerged with greater previous work levels, and indeed after 7.5 kJ·kg-1 above CP World Tour cyclists attained higher MMP values than both U23 and Pro Team cyclists for most efforts (≥30 s). CONCLUSION: Pro Team and particularly World Tour cyclists tolerate greater levels of accumulated work at high intensity, which might support the importance of high-intensity durability for performance.


Assuntos
Desempenho Atlético , Ciclismo , Humanos , Ciclismo/fisiologia , Masculino , Desempenho Atlético/fisiologia , Adulto Jovem , Fatores de Tempo
14.
J Strength Cond Res ; 27(9): 2405-13, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23249821

RESUMO

Little is known about the influence of speed endurance workouts on the improvement of pacing strategies in the 800-m running event. This study aims to analyze it, comparing continuous repetitions vs. interval training workouts. Because we hypothesize that pacing is susceptible to expertise, there might be age differences. Nineteen male 800-m runners (age: 21.36 ± 5.26, season best [SB]: 117.14 ± 5.18 seconds) were tested. Athletes were asked to run 1 × 600 m (6r) at 100% (SB) and 2 × 4 (200 m per 30 seconds) per 15 minutes (B8) at 102% (SB), counterbalanced and randomized within 1 week of difference. Pacing strategy (velocity dynamics) was analyzed by means of time differences in 200-m segments (T200), whereas age category was considered a grouping factor (younger than 23 years-senior, n = 10; vs. juvenile-junior, n = 9; 25.29 ± 4.32, 17.00 ± 0.66 years). Blood lactate was registered after 6r, B(8)1, and B(8)2 bouts. Univariate contrast analysis revealed a significant decrease in velocity during 6r (p < 0.001; 9.33% between first and third segment), thus a positive pacing, whatever the age category. B8 shared this final significant impairment (p < 0.001), although it was smaller (5.73% drop for B(8)1; 8.47% for B(8)2), and neither linear nor significant among consecutive T200. B8 also showed significant differences (p < 0.05) in the interaction sampling condition × age category. The T test added blood lactate significant differences (B(8)2: 15.42 ± 1.16, B(8)1: 12.25 ± 2.03 and 6r: 13.58 ± 1.82 mmol·L(-1)). Summarizing, both methods share a positive pacing, confirming to be related to enhancing energy systems and coping final fatigue in the 800 m. Continuous 6r preserves the nature and tempo of the 800 m, although 1 repetition is metabolically limited. Interval B8 allows larger amounts of high intensity running, enhancing neuromuscular benefits jointly with higher lactate productions. Significant age category differences in B8 indicate that pacing capacity may improve with expertise and interval workouts may be appropriate methods to manage it.


Assuntos
Corrida/fisiologia , Fatores Etários , Desempenho Atlético/fisiologia , Humanos , Lactatos/sangue , Masculino , Educação Física e Treinamento/métodos , Corrida/educação , Adulto Jovem
15.
Sports Biomech ; 22(7): 906-920, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32567482

RESUMO

Accelerometers are becoming popular in sport performance, as they are easy to wear, affordable, and usable in the field. Eccentric chainrings have been commercialised to improve pedalling performance, but little is known about their possible effects in the first pedal strokes (PS) of maximal sprint starts. To analyse the effects of the Q-Ring chainring (Q) on pedalling mechanics and performance in the BMX starting hill, 12 Spanish-National-Team BMX athletes performed 3 maximal sprints comparing Q vs No-Q. Time was measured in the first three meters. Acceleration output was registered with a triaxial 6 g accelerometer (200 Hz) in the first four PS. Discrete time, acceleration and statistical parametric mapping (SPM) were used to compare between conditions. Q showed no improvement in performance, despite a force-application time increasing (p = 0.013, ES = 0.39) and a reduction in the dead spot time (p = 0.028, ES = -0.73). Time after the four PS was greater (p = 0.006, ES = 0.63), and 3-m time did not change. Likewise, SPM 1D comparison showed no differences along the four PS. Therefore, accelerometry confirms its potential to evaluate pedalling technique in BMX, where Q-Ring fails to improve the pedalling mechanics in the starting hill.


Assuntos
Desempenho Atlético , Ciclismo , Humanos , Fenômenos Biomecânicos , Aceleração , Acelerometria , Atletas , Proteínas Tirosina Quinases
16.
Eur J Sport Sci ; 23(4): 580-587, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35238695

RESUMO

Background: The evaluation of performance in endurance athletes and the subsequent individualisation of training is based on the determination of individual physiological thresholds during incremental tests. Gas exchange or blood lactate analysis are usually implemented for this purpose, but these methodologies are expensive and invasive. The short-term scaling exponent alpha 1 of detrended Fluctuation Analysis (DFA-α1) of the Heart Rate Variability (HRV) has been proposed as a non-invasive methodology to detect intensity thresholds. Purpose: The aim of this study is to analyse the validity of DFA-α1 HRV analysis to determine the individual training thresholds in elite cyclists and to compare them against the lactate thresholds. Methodology: 38 male elite cyclists performed a graded exercise test to determine their individual thresholds. HRV and blood lactate were monitored during the test. The first (LT1 and DFA-α1-0.75, for lactate and HRV, respectively) and second (LT2 and DFA-α1-0.5, for lactate and HRV, respectively) training intensity thresholds were calculated. Then, these points were matched to their respective power output (PO) and heart rate (HR). Results: There were no significant differences (p > 0.05) between the DFA-α1-0.75 and LT1 with significant positive correlations in PO (r = 0.85) and HR (r = 0.66). The DFA-α1-0.5 was different against LT2 in PO (p = 0.04) and HR (p = 0.02), but it showed significant positive correlation in PO (r = 0.93) and HR (r = 0.71). Conclusions: The DFA1-a-0.75 can be used to estimate LT1 non-invasively in elite cyclists. Further research should explore the validity of DFA-α1-0.5.HighlightsThe power and heart rate values derived from the DFA-α1-0.75 threshold showed high levels of validity and agreement when they were compared against the first lactate threshold.The second lactate threshold and the DFA-α1-0.5 were different (p < 0.05) but showed high levels of correlation.The detrended fluctuation analysis is a valid method to estimate the first lactate threshold and more studies are needed to verify its validity with the second lactate threshold.


Assuntos
Teste de Esforço , Ácido Láctico , Humanos , Masculino , Frequência Cardíaca/fisiologia , Atletas
17.
Int J Sports Physiol Perform ; 18(10): 1141-1144, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37385604

RESUMO

PURPOSE: The record power profile (RPP) has gained popularity as a method of monitoring endurance cycling performance. However, the expected variation of cyclists' performance between seasons remains unknown. We aimed to assess the between-seasons variability of peak performance (assessed through the RPP) in male professional cyclists. METHODS: The study followed a longitudinal observational design. Sixty-one male professional cyclists (age 26 [5] y) with power output data from both training sessions and competitions were analyzed for a median of 4 consecutive seasons (range 2-12). The highest mean maximum power values attained for different durations (from 10 s to 30 min), as well as the resulting critical power, were determined for each season. Within-cyclist variability between seasons was assessed, and the upper threshold of expected changes (ie, twice the normal coefficient of variation) was determined. RESULTS: All mean maximum power values showed an overall high agreement and low variability between seasons (intraclass correlation coefficient [ICC] = .76-.88 and coefficient of variation [CV] = 3.2%-5.9%), with the lowest variability observed for long efforts (>1 min). Critical power showed an ICC and CV of .79 (95% CI, .70-.85) and 3.3% (95% CI, 3.0%-3.7%), respectively. Upper thresholds of expected variation were <12% for short efforts (≤1 min) and <8% for long efforts. CONCLUSIONS: "Real-world" peak performance assessed through the RPP shows a low variability between seasons in male professional cyclists-especially for long efforts-with expected variation being around 6% and 3% for short (≤1 min) and long efforts, respectively, and with changes >12% and >8%, respectively, being infrequent for these effort durations.


Assuntos
Ciclismo , Estado Nutricional , Humanos , Masculino , Adulto , Estações do Ano
18.
Int J Sports Physiol Perform ; 18(11): 1313-1320, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37709277

RESUMO

PURPOSE: The aim of this study was to describe individual training characteristics, racing strategies, and periodization in preparation for the Tour de France in 2 world-class road cyclists finishing in the top 5 of the general classification. METHODS: Week-by-week power meter training and racing data of 2 (A and B) road cyclists (age: 29 and 23 y; maximum oxygen consumption: 83 and 81 mL·min-1·kg-1; and relative 20-min record power output: 6.9 and 6.5 W·kg-1) in the preparation phase (December-July/August) leading up to the Tour de France were retrospectively analyzed. Weekly volume and intensity distribution in power zones were considered. RESULTS: Cyclists A and B completed 46 and 19 races, 22.5 (6.3) and 18.2 (5.1) h·wk-1, with a pyramidal intensity distribution of 81.0%-13.3%-5.7%, and 88.8%-7.9%-3.3% in zone 1-zone 2-zone 3. Cyclist B spent 14 days at altitude. Increased high-intensity volume and polarization index occurred during race weeks. During periods without racing, training intensity progressively increased. Strength training was performed during November and December but not during the following months. During tapering, total exercise volume and time at high intensity decreased. CONCLUSION: These data provide novel insights into the periodization of world-class road cyclists in advance of a top 5 placing in the Tour de France general classification.


Assuntos
Ciclismo , Resistência Física , Humanos , Estudos Retrospectivos , Comportamento Competitivo , Consumo de Oxigênio , França
19.
Int J Sports Physiol Perform ; 18(1): 27-36, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36470252

RESUMO

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.


Assuntos
Ciclismo , Humanos , Torque
20.
J Sports Sci Med ; 11(3): 502-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24149360

RESUMO

The objectives of this study were 1) to describe the technical requirements of different tracks where classifying points are disputed for the Olympics as the European continent tracks (E), world championship competitions tracks (W), and Olympic Games track - Beijing, 2008- (O); and 2) to compare and establish differences or similarities between the three previous contexts. The sample used for this study was made of the 8 best qualifying male athletes from each competition (n = 48) during the 2007 and 2008 seasons (pre-Olympic and Olympic years). A descriptive design was used, based on systematic structured observation of the competitions filmed on video, paying attention to the different techniques used (overtaking skills, complete pedalling cycles and registered effort times). The results show that aerial techniques predominate over non aerial techniques on O and W type tracks more than on E tracks by ~20% (p < 0.001), pedaling cycles predominate in E vs. W and O by 11.85 and 24.23% respectively (p ≤ 0.05), and effort times predominate in O vs. W and E by 6.50 and 12.94% respectively (p ≤ 0.01). In conclusion, O and W tracks stand out because of the aerial component and greater technical complexity in comparison to E tracks, which has a decisive effect on the way the riders train in relation to the type of championship they aim to compete in. Key pointsEuropean tracks involve more non aerial techniques than world and Olympic tracks, respectively; more non aerial techniques are associated with more pedaling effort time.Bicycle motocross cyclists develop greater values of aerial Techniques in World and Olympic tracks compared with the European tracks and, consequently, reduced non aerial techniques.European tracks involve less technical jumps but more simple jumps. World tracks involve more technical jumps than European and Olympic tracks, but Olympic track jumps, despite being less in number, are more difficult and decisive than the rest.Olympic and World class tracks involve less physical demand than European tracks because of the greater technical requirements and less pedaling cycles.Training should be developed according to the objectives established for each athlete taking into account the type of track in which the competition is going to take place.

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