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The goal of this study was to investigate the effects of photobiomodulation therapy (PBMT) on performance, oxygen uptake (VO2) kinetics, and lower limb muscle oxygenation during three successive time-to-exhaustions (TTEs) in cyclists. This was a double-blind, randomized, crossover, placebo-controlled trial study. Sixteen cyclists (~23 years) with a cycling training volume of ~460 km/week volunteered for this study. In the first session, cyclists performed a maximal incremental test to determine maximal oxygen uptake and maximal power output (POMAX). In the following sessions, cyclists performed three consecutive TTEs at POMAX. Before each test, PBMT (135 J/thigh) or a placebo (PLA) was applied to both thighs. VO2 amplitude, O2 deficit, time delay, oxyhemoglobin (O2Hb), deoxyhemoglobin (HHb), and total hemoglobin (tHb) were measured during tests on the right vastus lateralis. The PBMT applied before three successive TTE increased performance of the first and second TTE (~10-12%) tests, speed of VO2 and HHb kinetics during the first test, and increased peripheral muscle oxygenation (increase in HHb and tHb) in the first and second exhaustion tests. However, the PBMT effects were attenuated in the third TTE, as performance and all the other outcomes were similar to the ones from the PLA intervention. In summary, PBMT application increased the first and second successive TTEs, speed of VO2, and muscle oxygenation.

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The aim of this study was to determine if quadriceps morphology [muscle volume (MV); cross-sectional area (CSA)], vastus lateralis (VL) muscle architecture, and muscle quality [echo intensity (ECHO)] can explain differences in knee extensor maximal voluntary isometric contraction (MVIC), crank torque (CT) and time-to-exhaustion (TTE) in trained cyclists. Twenty male competitive cyclists performed a maximal incremental ramp to determine their maximal power output (POMAX). Muscle morphology (MV; CSA), muscle architecture of VL and muscle quality (ECHO) of both quadriceps muscles were assessed. Subsequently, cyclists performed three MVICs of both knee extensor muscles and finally performed a TTE test at POMAX with CT measurement during TTE. Stepwise multiple regression results revealed right quadriceps MV determined right MVIC (31%) and CT (33%). Left MV determined CT (24%); and left VL fascicle length (VL-FL) determined MVIC (64%). However, quadriceps morphological variables do not explain differences in TTE. No significant differences were observed between left and right quadriceps muscle morphology (p > 0.05). The findings emphasize that quadriceps MV is an important determinant of knee extensor MVIC and CT but does not explain differences in TTE at POMAX. Furthermore, quadriceps morphological variables were similar between the left and right quadriceps in competitive cyclists.

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Resumo O objetivo foi descrever características de uso e aspectos sociodemográficos e motivacionais de ciclistas usuários do sistema cicloviário da cidade de Pelotas, estado do Rio Grande do Sul. Foi realizado um estudo de métodos mistos com abordagem quantitativa e qualitativa. No total, 841 ciclistas foram amostrados aleatoriamente e entrevistados no componente transversal descritivo do estudo. A maior parte dos usuários eram homens (82,9%), pertencentes à faixa etária entre 30 e 59 anos (55,8%) e trabalhadores da construção civil ou do comércio (47,4%). Mais de 80% utilizam a bicicleta como deslocamento. Embora a grande maioria tenha relatado utilizar bicicleta mesmo em dias de verão e inverno rigorosos, apenas 56,6% relataram manter o uso em dias de chuva. Nove entrevistas semiestruturadas foram realizadas no componente qualitativo e emergiram barreiras como condições climáticas atreladas à qualidade das vias (dias de chuva), relações de trânsito conflituosas e necessidade de melhoria e ampliação das vias em direção aos bairros. Entre as motivações, foram destacadas questões de economia de gastos com transporte e de cuidados da saúde (entre os ciclistas de lazer). Os resultados encontrados apresentam subsídios específicos para intervenções de políticas públicas e necessidade de foco de acordo com seus usuários.

Abstract The scope of this study was to describe the characteristics of use and sociodemographic and motivational aspects of cyclists who travel on the cycle paths/lanes in the city of Pelotas (Brazil). A descriptive study was conducted applying mixed methods with quantitative and qualitative approaches. A total of 841 cyclists were randomly selected and assessed in the quantitative component. The majority of users were men (82.9%), from the middle age group (55.8%) and workers in the construction industry and local commerce (47.4%). More than 80% of the participants used the bicycle for commuting purposes. Although the large majority reported using the bicycle even in rigorous winter and summer conditions, only 56.6% reported use on rainy days. Nine interviews were performed in the qualitative component and the following barriers emerged: climate conditions related to the quality of streets, (rainy days); complex traffic systems; and the need for qualitative and quantitative improvement in the paths leading to outlying neighborhoods. Saving money with transport and health benefits (among leisure-time cyclists) are the main motivations for using a bicycle. The results reveal specific aspects for improvement in terms of public policies, and the need to prioritize specific user demands.

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Acute foam rolling protocols may increase range of motion without a negative impact on muscle performance. The main purpose of the present study was to investigate the acute effects of foam rolling on cycling performance (mean power and maximal power), affect and perceived exertion. A secondary aim was to assess the effect of foam rolling on post-exercise muscle soreness. In a random order, ten recreationally trained cyclists (age: 26 ± 5 years; height 1.76 ± 0.06 m; total body mass 78.3 ± 19.8 kg; cycling experience: 5.6 ± 5.3 years; 4.1 ± 1.3 cycling sessions per week and 1.4 ± 1.4 strength sessions per week) were submitted to the following experimental conditions (separated by one week) before performing a three-minute, all-out cycling test: foam rolling or control. During foam rolling protocol, participants were instructed to roll back and forth on one leg and to place the opposite leg crossed over, from the proximal to the distal portion of the rectus femoris and vastus lateralis during one set of sixty seconds for each muscle group. Feeling scale (10 min pre and post-test), CR-10 scale of perceived exertion (ten-minute post-test), pressure pain threshold (pre and 24 h post-test) and mean/maximal power were assessed. No significant differences were observed between conditions for mean and maximal power, affect, perceived exertion, and pressure pain threshold (all p > 0.05). In conclusion, a pre-exercise acute session of self-myofascial release does not improve performance and post-exercise muscle soreness of recreationally trained cyclists.

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Analisar o padrão do deslocamento ativo da Região Metropolitana Campinas, levando em conside-ração particularidades dos residentes e suas viagens. Utilizando as bases de dados obtidas através da Pesquisa Origem e Destino da Região Metropolitana de Campinas dos anos de 2003 e 2011, foram realizadas estatísticas descritivas e temporais a partir das características dos sujeitos, municípios e via-gens. Para identificarmos diferenças adotamos o intervalo de confiança de 95% (IC 95%). Utilizamos a regressão de Poisson para verificação da correlação entre características individuais e o desfecho ser ciclista ou caminhante, adotando o valor de p < 0,05. Todos os dados foram analisados levando-se em consideração os procedimentos de amostragem para que a amostra fosse representativa. Cons-tatou-se que a frequência de ciclistas e caminhantes e suas respectivas viagens caíram. Encontramos associação positiva para ciclista ser homem e classes econômicas mais baixas, para os caminhantes houve associação positiva ser mulher e crianças/adolescentes. Quanto ao tempo de viagem, notou-se aumento na mediana para os ciclistas e queda para os caminhantes. Não encontramos nenhuma via-gem de bicicleta que faça integração com outro modo de transporte. Quanto ao porte do município, observou-se uma queda em viagens de bicicleta tanto nos municípios pequenos, médios e grandes, e os residentes de Campinas apresentaram as menores frequências

This study analyzes the active commuting pattern of the Metropolitan Region of the City of Campinas, Brazil, by considering its commuters and their features. By using the database of Pesquisa Origem e Destino (a Brazilian instrument for transportation planning) of Campinas Metropolitan Region 2003-2011, we present descriptive and temporal statistics concerning the characteristics of the region's commuters, cities, and journeys. To assess those, we adopted a confidence interval of 95% (CI 95%). We used the Poisson regression to check the correlation between individual characteristics and outcomes of being a cyclist or a pedestrian, adopting the value of p < 0.05. We took into consideration the procedures for datum obtaining to present representative samples, verifying that the number of both cyclists and pedestrians has dropped. We found pos-itive associations regarding low-income males and being a cyclist; as well as females and children/teenagers and being pedestrians. The mean length of commuting time has increased for cycling journeys and decreased for pedestrian ones. We could not find a bicycle journey that integrates with another mean of transportation. Regarding the size of a city, we observed that the number of cycling journeys has dropped in small, medium, and large municipalities; Campinas presents the lowest index

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INTRODUCTION: As part of the transformation of urban transportation dynamics, commuter cycling has acquired a high relevance as an alternative mode of transport in different countries, and Latin America seems to be one of the main focus of this worldwide "revolution". However, the high rates of crashes and injuries suffered by commuters have become a relevant issue in the field of road safety, especially in emerging regions with low cycling tradition, where social and infrastructural gaps may endanger the cyclists' safety. OBJECTIVES: This study had two objectives. First, to compare key safe cycling-related variables between cycling commuters and non-commuters; and second, to differentially asses the effect of individual and cycling-related variables on their self-reported crash rates. METHOD: For this cross-sectional research, the data provided by 577 Latin American urban cyclists from three countries (Argentina, Colombia and Mexico) with a mean age of 32.7 years was used. They answered a questionnaire on cycling habits, risk perception, rule knowledge, cycling behaviors and riding crashes. RESULTS: The outcomes of this study showed that, despite having a higher risk perception, cycling commuters perform deliberate risky cycling behaviors (traffic violations) more frequently, and they suffer more crashes; cycling commuters report higher rates of psychological distress, and a lower degree of rule knowledge and protective behaviors than non-commuters. Furthermore, structural similarities and differences in the explanation of cycling crashes were found across commuters and non-commuters. CONCLUSION: The results of this study suggest that non-commuters, whose purposes for cycling are more aimed at leisure and occasional trips, perform less risky behaviors but suffer more cycling distractions, whereas commuters are comparatively more exposed to behavioral-based safety risks, and suffer more frequent crashes. Since recent evidence forecasts that urban cycling will keep growing in Latin American cities, it is necessary to implement policies and educational/training improvements that may enhance the safety and health of cyclists in these countries.

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BACKGROUND: Hydration status affects endurance performance. Pre-exercise hydration recommendations target the consumption of high carbohydrate and sodium beverages. Milk, due to its carbohydrate and sodium content, may be considered an effective pre-exercise hydration beverage. PURPOSE: In a randomized cross-over trial, we compared the effects of an isotonic sport drink (SPD) with skim milk (SM) consumption before a race, on fluid homeostasis and time-trial performance in road cyclists. METHODS: Male road cyclists (n = 9; age, 26.8 ± 4.78 years) with 10.8 ± 8.56 years of experience in national competitions, consumed either SPD or SM in doses of 350 mL at 3 h and 350 mL at 1.5 h before a 18.6 km time-trial race. Measurements of body mass, urine specific gravity (USG), urine color and time-trial were compared between drinks (group; g) before and after the race (time; t). RESULTS: The two-way ANOVA showed no differences between SPD and SM in body mass (t, p < 0.0001; g, p = 0.89; t × g, p = 0.54), USG (t, p = 0.01; g, p = 0.63; t × g, p = 0.29) and urine color (t, p = 0.01; g, p = 0.54; t × g, p = 0.28) before or after race. Furthermore, no differences on water consumption during the race (p = 0.55) or time-trial performance (p = 0.84) were observed between trials. CONCLUSION: Current results may help athletes with different beverages preferences to increase their options of hydration strategies.

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Abstract Aims: To evaluate whether body mass (BM) and body composition may influence mountain bike cycling performance. Methods: Forty male amateur mountain bikers attended the laboratory on two non-consecutive days. At the first visit, anthropometric measures (height, BM, body fat [BF], fat-free mass [FFM] and body mass index [BMI]) and familiarization to incremental cycling test were performed. On the second visit, cyclists performed again the incremental cycling test to measure peak power output (PPO), peak power output relative to BM (PPO-BM), and time to exhaustion (TE), which were posteriorly correlated with BM and anthropometric measures. Results: A low and moderate significant correlation were observed between TE and BM (p<0.01; r=0.40) and FFM (p<0.01; r=0.56). Moderate significant correlation was found between PPO and BM (p<0.01; r=0.45), BMI (p=0.03; r=0.35) and strong with FFM (p<0.01; r=0.59). Also, PPO-BM significantly correlated with BM (p=0.04; r=-0.31), BMI (p=0.02; r=-0.35) and BF (p<0.01; r=-0.55). No other significant correlations were observed. Conclusion: Considering PPO-BM as mainly performance variable, BM and BF can be a determining factor in mountain biking performance but FFM did not.

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Due to the controversy about the sensitive of lactate minimum intensity (LMI) to training and the need to develop other tool for aerobic fitness evaluation, the purpose of this study was to analyze the sensitivity of glucose minimum intensity (GMI) and LMI to endurance training. Eight trained male cyclists (21.4 ± 1.9 years, 67.6 ± 7.5 kg and 1.72 ± 0.10 m) were evaluated twice, before and after 12 weeks of training. GMI and LMI were calculated, respectively, by the lowest blood glucose and lactate values attained during an incremental test performed after a hyperlactemia induction, and VO2max was determined during standard incremental effort. The training was prescribed in three different zones and controlled by heart rate (HR). The training distribution was equivalent to 59.7%, 25.0% and 15.3% below, at and above anaerobic threshold HR respectively. The anaerobic threshold evaluated by GMI and LMI improvement 9.89 ± 4.35% and 10.28 ± 9.89 respectively, after training, but the VO2max 2.52 ± 1.81%. No differences were found between GMI and LMI in pre (218.2 ± 22.1 vs 215.0 ± 18.6 W) and post (240.6 ± 22.9 vs 237.5 ± 18.8 W) training situations. LMI and GMI were sensitive to 12-week aerobic training in cyclist; thus, both protocols can be used to assess aerobic adaptation, athletes diagnostic and prescribe training.

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The aim of this study was to determine the effects of block training (BL) on pacing during a 20-km hilly cycling time trial (TT) in trained cyclists. Twenty male cyclists were separated into 2 groups: control and BL. The training of each cyclist was monitored during a period of 3 weeks. In the first week cyclists performed an overload period of 7 consecutive days of high-intensity interval training followed by 2 weeks of normal training. Cyclists performed 1 TT before intervention and 2 TT after 7 and 14 days at the end of training. Each training session consisted of 10 sets of 3 repeated maximal-effort sprints (15, 30, and 45 s) with an effort/recovery duration ratio of 1:5. The main finding of this study was that the power output displayed a significantly higher start from the start until the halfway point of the TT (p < 0.05). Additionally, power output was characterized by a significant higher end spurt in the final 2 km in the BL after 2 weeks at the end of training (p < 0.05). In addition, after 2 weeks at the end of the overload period the distribution of cadence was significantly lower throughout the TT (p < 0.01). Therefore, a short period of consecutive days of intense training enhances cycling performance and changes the power output in the beginning and final part of the TT in trained cyclists.

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The validity of the Running-based Anaerobic Sprint Test (RAST) was investigated to evaluate the anaerobic power performance in comparison to Wingate test in cycling athletes. Ten mountain-bike male cyclists (28.0±7.3 years) randomly performed Wingate Test and RAST with two trials each. After several anthropometric measurements, peak power (PP), mean power (MP) and fatigue index (FI) for RAST and Wingate Test were analyzed using Student's paired t-test, Pearson's linear correlation test (r) and Bland and Altman's plots. Results showed that, with the exception of FI (33.8±4.6% vs. 37.8±7.9%; r=0.172), significant differences were detected between the Wingate and RAST tests with regard to PP and MP. Although there was a strong correlation for PP and MP, or rather, 0.831 and 0.714 respectively, agreement of analysis between Wingate and RAST protocols was low. The above suggested that RAST was not appropriate to evaluate the performance of anaerobic power by Wingate test in cycling athletes.

O objetivo foi investigar a validade do teste de RAST (Running-based Anaerobic Sprint Test) em avaliar o desempenho da potência anaeróbia a partir do teste de Wingate em ciclistas treinados. Participaram do estudo 10 ciclistas do sexo masculino (28,0±7,3 anos) da modalidade de Mountain bike. Após a mensuração das variáveis antropométricas, a potência pico (PP), média (PM) e o índice de fadiga (IF) foram determinados randomicamente a partir de dois testes de Wingate e dois testes de RAST. Foram utilizados o teste t independente de Student, a análise de correlação linear de Pearson (r) e o teste de Bland-Altman. Os resultados demonstraram, exceto para o IF (33.8±4.6% vs. 37.8±7.9%; r=0.172), diferenças significativas entre o teste de Wingate e o RAST para PP e PM (W.kg-1 e W). Embora os valores de correlação para a PP e PM (W) tenham sido fortes (0.831 e 0.714, respectivamente) a concordância entre os protocolos de Wingate e RAST foi baixa, sugerindo que o teste de RAST não é válido para avaliar o desempenho da potência anaeróbica a partir do teste de Wingate em ciclistas.

El objetivo fue investigar la validad del teste de RAST (Running-based Anaerobic Sprint Test) en evaluar el desempeño de la potencia anaeróbica través del uso del teste de Wingate en ciclistas trenados. Participaron del estudio 10 ciclistas masculinos (28,0±7,3 años) de la modalidad de Mountain bike. Después de la mensuración de las variables antropométricas, la potencia pico (PP), media (PM) y el índice de fatiga (IF) fueron determinados al acaso a partir de dos testes de Wingate y de dos testes de RAST. Fueron utilizados el test t independiente de Student, el análisis de correlación linear de Pearson (r) y el test de Bland-Altman. Los resultados demostraron, contrariamente al IF (33.8±4.6% vs. 37.8±7.9%; r=0.172), diferencias significativas entre el teste de Wingate y el RAST para PP y PM (W.kg-1 e W). Mismo que los valores de correlación de PP e PM (W) tengan sido fortes (0,831 e 0,714, respectivamente), la concordancia entre los protocolos de Wingate y RAST fue baja, sugiriendo que el teste de RAST no es válido para evaluar el desempeño de la potencia anaeróbica a partir del teste de Wingate en este grupo.

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O objetivo foi analisar a cinética do consumo de oxigênio (VO2) na potência crítica (PC), em indivíduos com diferentes níveis de aptidão aeróbia no ciclismo. Seis ciclistas treinados (GT) e sete indivíduos não-treinados (GNT) realizaram os seguintes protocolos em cicloergômetro: (a) progressivo até a exaustão para determinação do VO2max e sua respectiva intensidade (IVO2max); (b) três testes em cargas constantes até a exaustão a 95-110%IVO2max para determinação da PC; e (c) um teste em carga constante até a exaustão a 100%PC. No exercício a 100%PC, o componente lento expresso em valor absoluto (GT: 342,4±165,8 ml.min-1 vs. GNT: 571,3±170,1 ml.min-1) e relativo ao aumento do VO2 em exercício (GT: 10,0±4,6% vs. GNT: 26,6±7,3%) foram menores para GT. O VO2 ao final do exercício (GT: 89,8±8,4%VO2max vs. GNT: 97,4±2,8%VO2max) foi significativamente menor no grupo GT (ρ = 0,045), sendo similar ao VO2max no grupo GNT. Portanto, o nível de aptidão aeróbia pode influenciar as respostas do VO2 ao exercício em PC.

The objective was to analyze the oxygen uptake (VO2) kinetics during exercise performed at critical power (CP) in subjects with different aerobic status in cycling. Six trained cyclists (GT) and seven non-trained subjects (GNT) underwent to the following protocols in cyclergometer: (a) incremental to exhaustion to determine VO2max and its respective workload (IVO2max); b) three square-wave tests to exhaustion at 95-110% IVO2max to determine CP, and; (c) one square-wave test to exhaustion at 100%CP. During the exercise at CP the slow component expressed as absolute value (GT: 342.4±165.8 ml.min-1 vs. GNT: 571.3±170.1 ml.min-1) and as the relative contribution to the increase of VO2 during exercise (GT: 10.0±4.6% vs. GNT: 26.6±7.3%) were lower for trained subjects. The VO2 at the end of the exercise at PC (GT: 89.8±8.4%VO2max vs. GNT: 97.4±2.8%VO2max) was significantly lower in GT (ρ = 0.045), and similar to VO2max in GNT. Therefore, the aerobic level might influence the VO2 responses to exercise at PC.

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O objetivo do estudo foi comparar diferentes métodos de estimativa de gordura corporal em ciclistas de elite. A amostra foi composta por 15 atletas de alto nível, do sexo masculino, com idade média de 28,6 anos. Gordura corporal foi estimada pela equação para espessura de dobras cutâneas (EDC), análise da bioimpedância elétrica (BIA) e absortometria de radiológica de dupla energia (DEXA) (utilizada como referência). O teste t pareado comparou as diferenças entre os métodos e o coeficiente de correlação intraclasse analisou o relacionamento entre os mesmos. Foi observado que os valores do percentual de gordura corporal estimado pela BIA (p= 0,029), mas não o estimado pela EDC (p= 0,094) diferiram das estimativas da DEXA. Dessa maneira, é possível concluir que EDC apresentou estimativas mais próximas daquelas fornecidas pelo DEXA.

The present study aimed at comparing different methods to estimate the body fatness of elite athletes. The sample consisted of 15 male elite athletes with mean age of 28.6 years. The body fatness was estimated by the skinfold (EDC), bioelectric impedance analysis (BIA) and the dual-energy X-ray absorptiometry (DEXA) (reference). The paired t-tests compared the differences among methods, and the intraclass correlation coefficient analyzed the relationship among them. BIA (p= 0.029) overestimated the body fatness provided by DEXA, but EDC (p= 0.094) did not overestimate. Therefore, it is possible to conclude that EDC presented the body fatness similar to DEXA.

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O objetivo do presente estudo foi comparar, em domínio muito intenso de exercício, diferentes técnicas utilizadas para medir a amplitude do componente lento (CL) da cinética do consumo de oxigênio. Dez ciclistas treinados, do gênero masculino [média ± DP (idade: 25 ± 3,6 anos, massa corporal: 67,2 ± 4,5kg, altura: 174,8 ± 6,5cm e VO2max: 62,4 ± 3,1ml.kg¹.min¹)], realizaram duas idênticas transições de carga constante (intensidade de 75 por centodelta: 75 por cento da diferença entre o VO2 no limiar de lactato e o VO2max) em dias diferentes. O CL foi calculado a partir de diferentes métodos: (1) modelo biexponencial [VO2(t) = VO2base + A1 (1 e-(t-TA1/t1)) + A2 (1 e(tTA2/t2))], (2) intervalos predeterminados (o deltaVO26-2: diferença do VO2 entre o segundo e o sexto minuto de exercício e o deltaVO263: diferença do VO2 entre o terceiro e o sexto minuto de exercício) e (3) diferença entre o VO2 obtido no final do exercício e o valor obtido a partir de um ajuste monoexponencial do "componente primário" (tempo predeterminado de 120s) (CL6"CP"). Todos os métodos foram comparados entre si. Os resultados demonstraram significante subestimação do CL obtido pelo método de intervalos predeterminados (deltaVO26-2: 432 ± 126ml.min¹ e deltaVO263: 279 ± 88ml.min¹) quando comparado com o modelo biexponencial (676 ± 136ml.min¹) e ao CL6"CP" [(719 ± 265ml.min¹ (p < 0,05)]. Não houve diferenças significativas entre as outras comparações. Os resultados sugerem que a utilização de tempos predeterminados pode subestimar o CL quando comparado com o modelo biexponencial e com o CL6"CP".

The objective of the present study was to compare in severe exercise domain, different techniques used for measuring the amplitude of the slow component (SC) of oxygen uptake kinetics. Ten trained cyclists, male (age: 25 ± 3.6 years, body mass: 67.2 ± 4.5 kg, height: 174.8 ± 6.5 cm and VO2max: 62.4 ± 3.1 mL.kg¹.min¹), performed two identical bouts transitions at constant load [mean ± SD (intensity 75 percentdelta: 75 percent of the difference between the VO2 lactate threshold and the VO2max)] in different days. The SC was calculated from different methods: (1) bi-exponential model [VO2(t) = VO2base + A1 (1 e(tTA1/t1)) + A2 (1 e(tTA2/t2))], (2) predetermined intervals (deltaVO262: difference between the second min VO2 and the end VO2; deltaVO263: difference between the third min VO2 and the end VO2) and (3) difference between the end VO2 and the value obtained from a mono-exponential adjustment of the "primary component" (predetermined time of 120 s) (SC6"PC"). All the methods were compared among themselves. The results showed a significant underestimation of the SC obtained by method of predetermined intervals (deltaVO262: 432 ± 126 ml.min¹ and deltaVO26-3: 279 ± 88 ml.min-1) when compared with bi-exponential model (676 ± 136 ml.min-1) and SC6-"PC" [(719 ± 265 ml.min-1 (p < 0.05)]. There was not significant difference among the other comparison. The results suggest that the use of predetermined time may underestimate the SC when compared with bi-exponential model and SC6"PC".

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