RESUMEN
Brain Complexity (BC) have successfully been applied to study the brain electroencephalographic signal (EEG) in health and disease. In this study, we employed recurrence entropy to quantify BC associated with the neurophysiology of movement by comparing BC in both resting state and cycling movement. We measured EEG in 24 healthy adults and placed the electrodes on occipital, parietal, temporal and frontal sites on both the right and left sides of the brain. We computed the recurrence entropy from EEG measurements during cycling and resting states. Entropy is higher in the resting state than in the cycling state for all brain regions analysed. This reduction in complexity is a result of the repetitive movements that occur during cycling. These movements lead to continuous sensorial feedback, resulting in reduced entropy and sensorimotor processing.
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Electroencefalografía , Entropía , Humanos , Adulto , Masculino , Femenino , Corteza Cerebral/fisiología , Neuronas/fisiología , Adulto Joven , Ciclismo/fisiología , Movimiento/fisiología , Descanso/fisiologíaRESUMEN
This study aimed to investigate the effects of caffeine ingestion by chewing gum (GUMCAF) combined with priming exercise on pulmonary oxygen uptake (VËO2) and near-infrared spectroscopy-derived muscle oxygen extraction (HHb + Mb) kinetics during cycling performed in a severe-intensity domain. Fifteen trained cyclists completed four visits: two under a placebo gum (GUMPLA) and two under GUMCAF ingestion. Each visit consisted of two square-wave cycling bouts at Δ70 intensity (70% of difference between the VËO2 at first ventilatory threshold and VËO2max) with duration of 6 min each and 5 min of passive rest between the bouts. The GUMPLA or GUMCAF (400 mg) was chewed for 5 min, 12 min before the first Δ70 bout in a randomized double-blind procedure. The fundamental phase and slow component of HHb + Mb and VËO2 kinetics were evaluated. For HHb + Mb kinetics, regardless of ingested gum, priming exercise effects occurred on the time constant (GUMCAF 16.0 ± 4.0 vs. 13.9 ± 2.9 s; GUMPLA 15.7 ± 6.1 vs. 13.2 ± 2.5 s), amplitude, slow component, time delay, and mean response time parameters (p ≤ .032). For VËO2 kinetics, there were significant effects of bouts on the amplitude, slow component, end VËO2, and the gain kinetics parameters (p < .017). Baseline VËO2 was higher during GUMCAF than GUMPLA (p = .020). No significant effects occurred for the interaction between gum and bout in any parameter of VËO2 or HHb + Mb kinetics. Therefore, unlike the priming exercise in severe-intensity exercise, GUMCAF is not an effective strategy for improving VËO2 or HHb + Mb kinetics acceleration.
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Ciclismo , Cafeína , Goma de Mascar , Estudios Cruzados , Músculo Esquelético , Consumo de Oxígeno , Espectroscopía Infrarroja Corta , Humanos , Método Doble Ciego , Ciclismo/fisiología , Adulto , Masculino , Cafeína/administración & dosificación , Cafeína/farmacología , Músculo Esquelético/metabolismo , Músculo Esquelético/efectos de los fármacos , Adulto Joven , Cinética , Ejercicio Físico/fisiologíaRESUMEN
Recent heatwaves have highlighted the importance of accurate and continuous core temperature (TCORE) monitoring in sports settings. For example, accentuated rises in TCORE caused by physical exercises under environmental heat stress increase the risk of heat illnesses. Thus, using valid and reproducible devices is essential to ensure safe sports practice. In this study, we assessed the validity and reproducibility of the Calera Research Sensor (CRS) in estimating the TCORE of male and female participants during cycling exercise in a hot environment. Seven male (age: 36.2 ± 10.1 years) and eight female cyclists (age: 30.1 ± 5.0 years) underwent two identical cycling trials in a dry-bulb temperature of 32 °C and relative humidity of 60%. The protocol consisted of an initial 10-min rest followed by a 60-min exercise comprising 10 min at 20%, 25 min at 55%, and 25 min at 75% of maximal aerobic power, and an additional 25 min of post-exercise recovery. TCORE was recorded simultaneously every minute using a gastrointestinal capsule (TGi) and the CRS (TSENSOR). Bland-Altman analysis was performed to calculate bias, upper (LCS) and lower (LCI) concordance limits, and the 95% confidence interval (95%CI). The maximum acceptable difference between the two devices was predetermined at ±0.4 °C. A mixed linear model was used to assess the paired differences between the two measurement systems, considering the participants, trials, and environmental conditions as random effects and the cycling stages as fixed effects. An intra-class correlation coefficient (ICC) of 0.98 was recorded when analyzing data from the entire experiment. A non-significant bias value of 0.01 °C, LCS of 0.38 °C, LCI of -0.35 °C, and CI95% of ±0.36 °C were found. When analyzing data according to the participants' sex, CRS reproducibility was high in both sexes: ICC values of 0.98 and 0.99 were reported for males and females, respectively. CI95% was 0.35 °C in experiments with males and 0.37 °C with females, thereby falling within the acceptable margin of difference. Therefore, CRS was considered valid (compared to TGi) and reproducible in estimating TCORE in both sexes at various intensities of cycling exercise in the heat.
Asunto(s)
Ciclismo , Temperatura Corporal , Calor , Humanos , Masculino , Adulto , Femenino , Ciclismo/fisiología , Reproducibilidad de los Resultados , Ejercicio Físico , Adulto JovenRESUMEN
Inaugurado em 2003, o Caminho da Fé (CF) é uma rota de peregrinação de mais de 300 Km. Ele tem início em Águas da Prata/SP e termina na Basílica de Aparecida (Aparecida/SP). Anualmente o CF atrai mais de 40 mil peregrinos, sendo que mais da metade são de cicloturistas. O objetivo deste artigo é analisar como os cicloturistas percebem as paisagens neste caminho. Como metodologia utilizamos: pesquisa qualitativa; observação através de cicloviagens; diário de campo; e, um questionário semiestruturado. Indagamos os cicloturista quanto às paisagens que mais lhes chamavam atenção. Como resultado encontramos respostas que foram em direção as paisagens naturais, destacando-se paisagens olfativas e sonoras, entre outras.
Opened in 2003, the Way of Faith (CF) is a pilgrimage route of more than 300 km. It starts in Águas da Prata/SP, and ends at the Basilica of Aparecida (Aparecida)/SP. Every year the CF CF attracts more than 40 thousand pilgrims, of which more than half are cycle tourists. The objective of this article is to analyze how cycle tourists perceive the landscapes on this path. As methodology we use: qualitative research; observation through cycl trips; field journal; and, a semi-structured questionnaire. We asked cycle tourists about the landscapes that most caught their attention. As a result, we found answers that focused on natural landscapes, highlighting olfactory and sound landscapes, among others.
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Ciclismo , Observación , Cultura , Investigación Cualitativa , AmbienteRESUMEN
This study aimed to describe a quantitative survey conducted with leaders to investigate effective and feasible actions that can be evaluated in computational models to inform policies to promote active mobility based in the city of São Paulo, Brazil. In 2022, an online survey was conducted during the Health Survey in São Paulo (Physical Activity and Environment study), which is monitored by representatives of nongovernmental organizations and public and private sector managers. A questionnaire was elaborated with three questions with 13 alternative answers about actions to promote walking and/or cycling. Leaders should select up to three alternatives based on their potential regarding: (1) effectiveness; (2) feasibility or ease of implementation; and (3) desire to verify tests in computational models to inform policies. The survey was answered by 18 leaders from 16 institutions, comprising 13 (72%) women and 12 (67%) representatives of the third sector, whose average age was 48 years and all had complete higher education. Reducing the speed of motor vehicles was the most cited option in all three questions. Other actions mentioned refer to controlling the traffic of vehicles in central areas, improving pedestrian safety, reducing the distances between homes and places of employment, conducting educational campaigns, and expanding and enhancing structures such as bicycle lanes and sidewalks. The results are relevant to support evidence-based decision-making in public management and to provide subsidies for the development of computational models with a view to promoting active mobility.
Este estudo teve como objetivo descrever um inquérito quantitativo realizado com lideranças para investigar ações efetivas, viáveis e que podem ser testadas em modelos computacionais para informar políticas de promoção da mobilidade ativa, tendo como base a cidade de São Paulo, Brasil. Em 2022, foi realizado um inquérito online no contexto da pesquisa de Atividade Física e Ambiente do Inquérito de Saúde de São Paulo, acompanhada por representantes de organizações não governamentais, gestores públicos e de entidades privadas. Foi elaborado questionário com três perguntas com 13 alternativas de respostas sobre ações para promoção da caminhada ou uso de bicicleta. As lideranças deveriam selecionar até três alternativas a partir de seu potencial em termos de (1) efetividade; (2) viabilidade ou facilidade de implementação; e (3) desejo de realizar testes em modelos computacionais para informar políticas. O inquérito foi respondido por 18 lideranças de 16 instituições, sendo 13 (72%) mulheres e 12 (67%) representantes do terceiro setor, cuja média de idade era 48 anos, todos com nível superior de escolaridade. A redução da velocidade dos veículos motorizados foi a opção mais citada nas três questões. Outras ações citadas referem-se ao controle de circulação de veículos em regiões centrais, à segurança de pedestres, à diminuição das distâncias entre residências e locais de emprego, às campanhas educativas e à ampliação e melhoria de estruturas como ciclovias e calçadas. Os resultados são relevantes para apoiar a tomada de decisões baseadas em evidências na gestão pública e oferecer subsídios para a elaboração de modelos computacionais com vistas à promoção da mobilidade ativa.
Este estudio tuvo como objetivo presentar una encuesta cuantitativa realizada con líderes para investigar las acciones efectivas, viables y que puedan probarse en modelos informáticos para orientar las políticas que promuevan la movilidad activa en la ciudad de São Paulo, Brasil. En 2022 se realizó una encuesta en línea en el contexto de la Encuesta de Salud de São Paulo (Actividad Física y Medio Ambiente), que es monitoreada por representantes de organizaciones no gubernamentales, gestores públicos y entidades privadas. Se elaboró un cuestionario de tres preguntas con 13 respuestas alternativas sobre acciones para promover la caminata o el uso de la bicicleta. Los líderes podían seleccionar hasta tres alternativas en función de su potencial en términos de (1) efectividad; (2) viabilidad o facilidad de implementación; y (3) deseo de verificar las pruebas en modelos informáticos para orientar las políticas. La encuesta fue respondida por 18 líderes de 16 instituciones; de los cuales 13 (72%) eran mujeres y 12 (67%) representaban el tercer sector; la edad promedio de ellos fue de 48 años y todos contaban con educación superior. Reducir la velocidad de los vehículos de motor fue la opción más citada en las tres preguntas. Otras acciones mencionadas se refieren al control de la circulación de vehículos en las regiones centrales, la seguridad de los peatones, la reducción de las distancias entre los hogares y los lugares de trabajo, las campañas educativas y la expansión y mejora de estructuras como carriles bici y aceras. Los resultados son relevantes para apoyar la toma de decisiones basada en la evidencia en la gestión pública y ofrecer subsidios para la elaboración de modelos computacionales destinados a promover la movilidad activa.
Asunto(s)
Promoción de la Salud , Sector Privado , Sector Público , Humanos , Brasil , Femenino , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Promoción de la Salud/métodos , Caminata/estadística & datos numéricos , Ciclismo/estadística & datos numéricos , Adulto , Ejercicio FísicoRESUMEN
It has been assumed that exercise intensity variation throughout a cycling time trial (TT) occurs in alignment of various metabolic changes to prevent premature task failure. However, this assumption is based on target metabolite responses, which limits our understanding of the complex interconnection of metabolic responses during exercise. The current study characterized the metabolomic profile, an untargeted metabolic analysis, after specific phases of a cycling 4-km TT. Eleven male cyclists performed three separated TTs in a crossover counterbalanced design, which were interrupted at the end of the fast-start (FS, 600 ± 205 m), even-pace (EP, 3600 ± 190 m), or end-spurt (ES, 4000 m) phases. Blood samples were taken before any exercise and 5 min after exercise cessation, and the metabolomic profile characterization was performed using Nuclear Magnetic Resonance metabolomics. Power output (PO) was also continually recorded. There were higher PO values during the FS and ES compared to the EP (all p < 0.05), which were accompanied by distinct metabolomic profiles. FS showed high metabolite expression in TCA cycle and its related pathways (e.g., glutamate, citric acid, and valine metabolism); whereas, the EP elicited changes associated with antioxidant effects and oxygen delivery adjustment. Finally, ES was related to pathways involved in NAD turnover and serotonin metabolism. These findings suggest that the specific phases of a cycling TT are accompanied by distinct metabolomic profiles, providing novel insights regarding the relevance of specific metabolic pathways on the process of exercise intensity regulation.
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Ciclismo , Estudios Cruzados , Metaboloma , Humanos , Masculino , Metaboloma/fisiología , Adulto , Ciclismo/fisiología , Ciclo del Ácido Cítrico , Serotonina/sangre , NAD/sangre , NAD/metabolismo , Adulto Joven , Ácido Glutámico/sangre , Ácido Glutámico/metabolismo , Metabolómica , Valina/sangre , Ácido Cítrico/sangreRESUMEN
Little is known about how the associations between active transportation and community participation may vary across national contexts. Using representative datasets from China, Ghana, India, Mexico, Russia, and South Africa collected in the Study on Global Ageing and Adult Health (N = 33,535), we estimated multi-group confirmatory factor analyses, tests of measurement invariance, and predictive models. Standardized coefficients were equivalent across countries and showed a modest positive association between active transportation and community participation (the variance explained by active transportation ranged from 1.3% to 7.5% across countries). These results suggest that supporting active transportation can help mitigate negative environmental and health changes associated with increased vehicular travel and support social capital via community participation.
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Participación de la Comunidad , Comparación Transcultural , Transportes , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Ghana , Envejecimiento , China , México , Federación de Rusia , Ciclismo/estadística & datos numéricos , Encuestas y Cuestionarios , India , Sudáfrica , Salud GlobalRESUMEN
BACKGROUND: Transportation policies can impact health outcomes while simultaneously promoting social equity and environmental sustainability. We developed an agent-based model (ABM) to simulate the impacts of fare subsidies and congestion taxes on commuter decision-making and travel patterns. We report effects on mode share, travel time and transport-related physical activity (PA), including the variability of effects by socioeconomic strata (SES), and the trade-offs that may need to be considered in the implementation of these policies in a context with high levels of necessity-based physical activity. METHODS: The ABM design was informed by local stakeholder engagement. The demographic and spatial characteristics of the in-silico city, and its residents, were informed by local surveys and empirical studies. We used ridership and travel time data from the 2019 Bogotá Household Travel Survey to calibrate and validate the model by SES. We then explored the impacts of fare subsidy and congestion tax policy scenarios. RESULTS: Our model reproduced commuting patterns observed in Bogotá, including substantial necessity-based walking for transportation. At the city-level, congestion taxes fractionally reduced car use, including among mid-to-high SES groups but not among low SES commuters. Neither travel times nor physical activity levels were impacted at the city level or by SES. Comparatively, fare subsidies promoted city-level public transportation (PT) ridership, particularly under a 'free-fare' scenario, largely through reductions in walking trips. 'Free fare' policies also led to a large reduction in very long walking times and an overall reduction in the commuting-based attainment of physical activity guidelines. Differential effects were observed by SES, with free fares promoting PT ridership primarily among low-and-middle SES groups. These shifts to PT reduced median walking times among all SES groups, particularly low-SES groups. Moreover, the proportion of low-to-mid SES commuters meeting weekly physical activity recommendations decreased under the 'freefare' policy, with no change observed among high-SES groups. CONCLUSIONS: Transport policies can differentially impact SES-level disparities in necessity-based walking and travel times. Understanding these impacts is critical in shaping transportation policies that balance the dual aims of reducing SES-level disparities in travel time (and time poverty) and the promotion of choice-based physical activity.
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Ejercicio Físico , Transportes , Caminata , Humanos , Colombia , Transportes/métodos , Caminata/estadística & datos numéricos , Impuestos , Factores Socioeconómicos , Ciudades , Ciclismo/estadística & datos numéricos , Femenino , Masculino , AdultoRESUMEN
Postexercise hydration is fundamental to replace fluid loss from sweat. This study evaluated rehydration and gastrointestinal (GI) symptoms for each of three beverages: water (W), sports drink (SD), and skimmed, lactose-free milk (SLM) after moderate-intensity cycling in the heat. Sixteen college students completed three exercise sessions each to lose ≈2% of their body mass. They drank 150% of body mass loss of the drink assigned in randomized order; net fluid balance, diuresis, and GI symptoms were measured and followed up for 3 hr after completion of fluid intake. SLM showed higher fluid retention (â¼69%) versus W (â¼40%; p < .001); SD (â¼56%) was not different from SLM or W (p > .05). Net fluid balance was higher for SLM (-0.26 kg) and SD (-0.42 kg) than W (-0.67 kg) after 3 hr (p < .001), resulting from a significantly lower diuresis with SLM. Reported GI disturbances were mild and showed no difference among drinks (p > .05) despite ingestion of W (1,992 ± 425 ml), SD (1,999 ± 429 ml), and SLM (1,993 ± 426 ml) in 90 min. In conclusion, SLM was more effective than W for postexercise rehydration, showing greater fluid retention for the 3-hr follow-up and presenting with low-intensity GI symptoms similar to those with W and SD. These results confirm that SLM is an effective option for hydration after exercise in the heat.
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Bebidas , Ejercicio Físico , Fluidoterapia , Enfermedades Gastrointestinales , Leche , Equilibrio Hidroelectrolítico , Humanos , Masculino , Adulto Joven , Femenino , Fluidoterapia/métodos , Ejercicio Físico/fisiología , Animales , Lactosa/análisis , Adulto , Deshidratación , Agua/administración & dosificación , Estudios Cruzados , Ingestión de Líquidos , Ciclismo/fisiología , Diuresis , Calor , Fenómenos Fisiológicos en la Nutrición DeportivaRESUMEN
PURPOSE: This study aimed to cross-validate a recently proposed equation for the prediction of maximal oxygen uptake (VËO2max) in cycling exercise by using the average power output normalized by the body mass from a 5-minute time trial (RPO5-min) as the independent variable. Further, the study aimed to update the predictive equation using Bayesian informative prior distributions and meta-analysis. METHODS: On different days, 49 male cyclists performed an incremental graded exercise test until exhaustion and a 5-minute time trial on a stationary cycle ergometer. We compared the actual VËO2max with the predicted value obtained from the RPO5-min, using a modified Bayesian Bland-Altman agreement analysis. In addition, this study updated the data on the linear regression between VËO2max and RPO5-min, by incorporating information from a previous study as a Bayesian informative prior distribution or via meta-analysis. RESULTS: On average, the predicted VËO2max using RPO5-min underestimated the actual VËO2max by -6.6 mL·kg-1·min-1 (95% credible interval, -8.6 to -4.7 mL·kg-1·min-1). The lower and upper 95% limits of agreement were -17.2 (-22.7 to -12.3) and 3.8 (-1.0 to 9.5) mL·kg-1·min-1, respectively. When the current study's data were analyzed using the previously published data as a Bayesian informative prior distribution, the accuracy of predicting sample means was found to be better when compared with the data combined via meta-analyses. CONCLUSIONS: The proposed equation presented systematic bias in our sample, in which the prediction underestimated the actual VËO2max. We provide an updated equation using the previous one as the prior distribution, which could be generalized to a greater audience of cyclists.
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Teorema de Bayes , Ciclismo , Prueba de Esfuerzo , Consumo de Oxígeno , Humanos , Consumo de Oxígeno/fisiología , Masculino , Ciclismo/fisiología , Prueba de Esfuerzo/métodos , Adulto , Adulto Joven , Factores de TiempoRESUMEN
A presença das bicicletas em Fortaleza, uma capital brasileira que tem ampliado a oferta de rotas cicláveis, ciclovias e ciclofaixas, é notada em diversas regiões da cidade e pode ser percebida como elemento fundamental na paisagem e tem forte influência nas alterações do tecido urbano de Fortaleza, desde a intensa manifestação cidadã em sua defesa como meio de transporte ou através da arte urbana. O estudo baseia-se em pesquisa exploratória, bibliográfica e documental, com observação participante e realização de grupo focal; traz reflexões sobre a bicicleta como bem simbólico, como elemento comunicativo, indutor do direito à cidade e instrumento de desenvolvimento urbano sustentável. Dialogando com Armando Silva (2014), Jane Jacobs (2011), Michel Maffesoli (2014), Fernanda Sánchez (2010), Jean-Mar Besse (2014), arguimos a importância do artefato bicicleta como elemento dinâmico na composição da paisagem cultural de Fortaleza.
The presence of bicycles in Fortaleza, a Brazilian capital that has expanded the offer of cycling routes, cycle paths and cycle lanes, is noted in several regions of the city and can be perceived as a fundamental element in the landscape and has a strong influence on changes to the urban fabric of Fortaleza, from the intense citizen demonstration in defense of it as a means of transport or through urban art. The study is based on exploratory, bibliographic and documentary research, with participant observation and focus groups; brings reflections on the bicycle as a symbolic asset, as a communicative element, an inducer of the right to the city and an instrument of sustainable urban development. Dialoguing with Armando Silva (2014), Jane Jacobs (2011), Michel Maffesoli (2014), Fernanda Sánchez (2010), Jean-Mar Besse (2014), we argue the importance of the bicycle artifact as a dynamic element in the composition of the cultural landscape of Fortaleza.
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Transportes , Ciclismo , Área Urbana , Economía , Enclave ÉtnicoRESUMEN
A motivação é um fenômeno complexo que impulsiona as ações humanas. O diagnóstico de tais interesses oferece elementos de reflexão para a promoção de atividades e a implementação de políticas públicas. Neste contexto, o presente trabalho tem o objetivo de analisar as motivações dos praticantes de ciclismo recreacional de Blumenau/SC, município com uma população de 363 mil habitantes e uma malha cicloviária de 137 quilômetros. A coleta dos dados empíricos da pesquisa ocorreu por meio da aplicação de um questionário. Ao final, obteve-se uma amostra de 304 respondentes. Os resultados do estudo indicam a motivação para as atividades físicas ocupa papel central na relação com outros fatores de interesse, contribuindo para a superação de aspectos eventualmente desencorajadores. Em contrapartida, praticantes que têm outras motivações, como a interação social e o desenvolvimento pessoal, dependem mais de estímulos encorajadores, o que sugere que em tais casos existe a necessidade de maior incentivo para a prática do ciclismo recreacional. As conclusões deste estudo são relevantes para planejadores urbanos e gestores de comunicação. Ao mensurar a pertinência de causas motivadoras e desmotivadoras do ciclismo, os resultados da pesquisa indicam a importância de investir em infraestrutura adequada como a expansão da rede cicloviária e a criação de campanhas de divulgação, a fim de promover a bicicleta como meio de transporte e/ou recreação.
Motivation is a complex phenomenon that drives human actions. Diagnosing these interests provides elements for reflection in promoting activities and implementing public policies. In this context, the present study aims to analyze the motivations of recreational cyclists in Blumenau, SC (Brazil), a city with a population of 363,000 inhabitants and a cycling network of 137 kilometers. Empirical data for the research were collected through a questionnaire. Ultimately, a sample of 304 respondents was obtained. The study's results indicate that motivation for physical activities plays a central role in the relationship with other factors of interest, contributing to overcoming potentially discouraging aspects. Conversely, individuals motivated by other factors, such as social interaction and personal development, rely more on encouraging stimuli, suggesting that in such cases there's a need for greater incentives for recreational cycling. The conclusions of this study are relevant for urban planners and communication managers. By assessing the relevance of motivating and demotivating factors in cycling, the research results underscore the importance of investing in appropriate infrastructure, such as expanding the cycling network and launching promotional campaigns, to promote cycling as a means of transportation and/or recreation.
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Impulso (Psicología) , Movilidad en la Ciudad , Motivación , Transportes , CiclismoRESUMEN
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.
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Rendimiento Atlético , Ciclismo , Glucemia , Estudios Cruzados , Frecuencia Cardíaca , Isomaltosa , Ácido Láctico , Polisacáridos , Trehalosa , Humanos , Masculino , Ciclismo/fisiología , Método Doble Ciego , Trehalosa/administración & dosificación , Trehalosa/farmacología , Rendimiento Atlético/fisiología , Adulto , Glucemia/metabolismo , Glucemia/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Ácido Láctico/sangre , Polisacáridos/administración & dosificación , Polisacáridos/farmacología , Isomaltosa/análogos & derivados , Isomaltosa/administración & dosificación , Isomaltosa/farmacología , Suplementos Dietéticos , Índice Glucémico , Resistencia Física/efectos de los fármacos , Resistencia Física/fisiología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Fenómenos Fisiológicos en la Nutrición Deportiva , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/farmacología , Carbohidratos de la Dieta/administración & dosificación , Adulto Joven , Esfuerzo Físico/fisiología , Esfuerzo Físico/efectos de los fármacos , Glucógeno/metabolismoRESUMEN
To examine the effects of 7-days juçara powder (JP) intake on oxidative stress biomarkers and endurance and sprint cycling performances. In a randomized, placebo-controlled, crossover, and triple-blind study, 20 male trained cyclists were assigned to intake 10 g of JP (240 mg anthocyanins) or placebo (PLA) for 7 days and performed a cycling time-to-exhaustion (TTE). A 5 s cycling sprint was performed before and after the cycling TTE. Blood oxidative stress biomarkers and lactate concentration where evaluated 1 h before (T-1), immediately after (T0), and 1 h after (T1) the cycling TTE. The mean duration time for the cycling TTE was 8.4 ± 6.0% (63 ± 17 s) longer in the JP condition (JP: 751 ± 283 s) compared to PLA (688 ± 266 s) (P < 0.019). Two-way repeated measures Analysis of variance showed an increase in the JP condition for reduced glutathione (GSH) (P = 0.049) at T0 (P = 0.039) and T1 (P = 0.029) compared to PLA with a moderate effect size at T0 (d = 0.61) and T1 (d = 0.57). Blood lactate levels increased over time in both conditions (P ≤ 0.001). No differences were observed for the post-TTE sprint fatigue index, total phenols, protein carbonyls, and glutathione peroxidase activity. Seven-day intake of JP improved cycling endurance performance and increased GSH levels but had no effect on lactate and cycling sprint-induced fatigue.
Asunto(s)
Rendimiento Atlético , Ciclismo , Estudios Cruzados , Glutatión , Ácido Láctico , Estrés Oxidativo , Resistencia Física , Humanos , Masculino , Ciclismo/fisiología , Glutatión/sangre , Estrés Oxidativo/efectos de los fármacos , Rendimiento Atlético/fisiología , Adulto , Resistencia Física/efectos de los fármacos , Resistencia Física/fisiología , Ácido Láctico/sangre , Biomarcadores/sangre , Adulto Joven , Antocianinas/administración & dosificación , Antioxidantes/administración & dosificación , Suplementos DietéticosRESUMEN
Engagement in physical activity, across various sports, promotes a diverse microbiota in active individuals. This study examines the gut microbiota of Colombian athletes, specifically weightlifters (n = 16) and road cyclists (n = 13), compared to non-athletes (n = 15). Using Kruskal-Wallis tests, the physical activity level of a group of non-athletic individuals and the sports experience of a group of professional athletes is analyzed. The median age of participants is 24 years, comprising 25 men and 19 women. The microbiota is collected using fecal samples. Participants provided these samples during their pre-competitive stage, specifically during the concentration phase occurring two weeks prior to national competitions. This timing is chosen to capture the microbial composition during a period of heightened physical preparation. Questionnaire responses and microbial composition assessments identify disparities among groups. Microbial composition analysis explores core microbiome, abundance, and taxonomy using Pavian, MicrobiomeAnalyst 2.0, and GraPhlAn. ANCOM-BC2 reveals differentially abundant species. Road cyclists exhibit decreased Bacteria and increased Archaea abundance. Phylum-level variations included Planctomycetes, Acidobacteria, and Proteobacteria, while Bacteroidetes prevailed. Key families influencing gut microbiota are Bacteroidaceae, Muribaculaceae, and Selenomonadaceae. Weightlifters exhibit unique viral and archaeal community connections, while cyclists showed specialized microbial interplay influenced by endurance exercise. Correlation network analysis emphasizes distinctive microbial interactions within athlete groups, shedding light on the impact of physical activities on gut microbiota and athlete health.
Asunto(s)
Archaea , Atletas , Bacterias , Ciclismo , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/fisiología , Masculino , Femenino , Colombia , Adulto , Atletas/estadística & datos numéricos , Archaea/aislamiento & purificación , Adulto Joven , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/genética , Levantamiento de Peso/fisiología , Heces/microbiologíaRESUMEN
The objective of the study was to compare measurements of length, thickness, and cross-section area (CSA) of the patellar tendon (PT) among cyclists, runners, triathletes, and physically active individuals (control group). Forty healthy individuals (10 cyclists, 10 runners, 10 triathletes, and 10 physically active individuals) aged between 18 and 45 years (30.3 ± 8.6 years) participated in the study. PT was measured by a B-mode ultrasound system. To measure the length and thickness (in 5, 10, 15, and 20 mm of the PT length) the probe was positioned parallel to the tendon and to measure the CSA the probe was positioned perpendicularly in 25, 50, and 75% of the PT length. PT length data were analyzed using a one-way ANOVA to compare between groups and PT CSA and thickness were analyzed using a two-way ANOVA (group vs. position) to compare the variables among the groups with the post-hoc Tukey test. All statistical analyses were performed considering p < 0.05. We observed a significant difference, where cyclists had smaller PT thickness (regardless of the location measured) compared to the group of triathletes (p = 0.001) and the physically active group (p = 0.043). All other variables (length, thickness, and CSA) and interactions (local and position) were not significant. We concluded that regardless of the position where PT thickness is measured, cyclists have smaller PT thickness compared to triathletes and physically active individuals but similar when compared to runners. And no differences in the length and CSA of the PT between groups.
Asunto(s)
Ciclismo , Ligamento Rotuliano , Carrera , Ultrasonografía , Humanos , Adulto , Ligamento Rotuliano/diagnóstico por imagen , Ligamento Rotuliano/anatomía & histología , Masculino , Adulto Joven , Carrera/fisiología , Ultrasonografía/métodos , Femenino , Adolescente , Persona de Mediana Edad , AtletasRESUMEN
The aims of this study were (i) to estimate the functional threshold power (FTP) and critical power (CP) from single shorter time trials (TTs) (i. e. 10, 20 and 30 minutes) and (ii) to assess their location in the power-duration curve. Fifteen highly trained athletes randomly performed ten TTs (i. e. 1, 2, 3, 4, 5, 10, 20, 30, 50 and 60 minutes). FTP was determined as the mean power output developed in the 60-min TT, while CP was estimated in the running power meter platform according to the manufacturer's recommendations. The linear regression analysis revealed an acceptable FTP estimate for the 10, 20 and 30-min TTs (SEE≤12.27 W) corresponding to a correction factor of 85, 90 and 95%, respectively. An acceptable CP estimate was only observed for the 20-min TT (SEE=6.67 W) corresponding to a correction factor of 95%. The CP was located at the 30-min power output (1.0 [-5.1 to 7.1] W), which was over FTP (14 [7.0 to 21] W). Therefore, athletes and practitioners concerned with determining FTP and CP through a feasible testing protocol are encouraged to perform a 20-min TT and apply a correction factor of 90 and 95%, respectively.
Asunto(s)
Ciclismo , Prueba de Esfuerzo , Humanos , Prueba de Esfuerzo/métodos , Consumo de Oxígeno , Atletas , Factores de Tiempo , Resistencia FísicaRESUMEN
BACKGROUND: Supplementation with Angiotensin-(1-7) [(Ang-1-7)] has received considerable attention due to its possible ergogenic effects on physical performance. The effects of a single dose of Ang-(1-7) on the performance of mountain bike (MTB) athletes during progressive load tests performed until the onset of voluntary fatigue have previously been demonstrated. This study tested the effects of Ang-(1-7) in two different exercise protocols with different metabolic demands: aerobic (time trial) and anaerobic (repeated sprint). METHODS: Twenty one male recreational athletes were given capsules containing an oral formulation of HPßCD-Ang-(1-7) (0.8 mg) and HPßCD-placebo (only HPßCD) over a 7-day interval; a double-blind randomized crossover design was used. Physical performance was examined using two protocols: a 20-km cycling time trial or 4 × 30-s repeated all-out sprints on a leg cycle ergometer. Data were collected before and after physical tests to assess fatigue parameters, and included lactate levels, and muscle activation during the sprint protocol as evaluated by electromyography (EMG); cardiovascular parameters: diastolic and systolic blood pressure and heart rate; and performance parameters, time to complete (time trial), maximum power and mean power (repeated sprint). RESULTS: Supplementation with an oral formulation of HPßCD-Ang-(1-7) reduced basal plasma lactate levels and promoted the maintenance of plasma glucose levels after repeated sprints. Supplementation with HPßCD-Ang-(1-7) also increased baseline plasma nitrite levels and reduced resting diastolic blood pressure in a time trial protocol. HPßCD-Ang-(1-7) had no effect on the time trial or repeat sprint performance, or on the EMG recordings of the vastus lateralis and vastus medialis. CONCLUSIONS: Supplementation with HPßCD-Ang-(1-7) did not improve physical performance in time trial or in repeated sprints; however, it promoted the maintenance of plasma glucose and lactate levels after the sprint protocol and at rest, respectively. In addition, HPßCD-Ang-(1-7) also increased resting plasma nitrite levels and reduced diastolic blood pressure in the time trial protocol. TRIAL REGISTRATION: RBR-2nbmpbc, registered January 6th, 2023. The study was prospectively registered.
Asunto(s)
Angiotensina I , Rendimiento Atlético , Nitritos , Fragmentos de Péptidos , Humanos , Masculino , Estudios Cruzados , 2-Hidroxipropil-beta-Ciclodextrina , Ciclismo/fisiología , Glucemia , Lactatos , Suplementos Dietéticos , Atletas , FatigaRESUMEN
BACKGROUND: Intensive care acquired muscle weakness is a common feature in critically ill patients. Beyond the therapeutic uses, FES-cycling could represent a promising nonvolitional evaluation method for detecting acquired muscle weakness. OBJECTIVES: To assess whether FES-cycling is able to identify muscle dysfunctions, and to evaluate the survival rate in patients with detected muscle dysfunction. METHODS: A prospective observational study was carried out, with 29 critically ill patients and 20 healthy subjects. Maximum torque and power achieved were recorded, in addition to the stimulation cost, and patients were followed up for six months. RESULTS: Torque (2.64 [1.53 to 4.81] vs 6.03 [4.56 to 6.73] Nm) and power (3.31 [2.33 to 6.37] vs 6.35 [5.22 to 10.70] watts) were lower and stimulation cost (22 915 [5069 to 37 750] vs 3411 [2080 to 4024] µC/W) was higher in patients compared to healthy people (p < 0.05). Surviving patients showed a nonsignificant difference in power and torque in relation to nonsurvivors (p > 0.05), but they had a lower stimulation cost (4462 [3598 to 11 788] vs 23 538 [10 164 to 39 836] µC/W) (p < 0.05). In total, 34% of all patients survived during the six months of follow-up. Furthermore, 62% of patients with a stimulation cost below 15 371 µC/W and 7% of patients with a stimulation cost above 15 371 µC/W survived. CONCLUSIONS: FES-cycling has good sensitivity and specificity for detecting muscle disorders. Critical patients have low torque and power and a high stimulation cost. Stimulation cost is related to survival. A low stimulation cost was related to a 3 times greater chance of survival.