The Distinguishing Factor in Soccer Players is Aerobic Performance, not the ACTN3 Gene / El Factor Distintivo en los Jugadores de Fútbol es el Rendimiento Aeróbico y no el gen ACTN3

SUMMARY: The purpose of this study was to reveal the differences between ACTN3 genotype (RR, RX, XX) and aerobic performance [Yo-Yo IRT1 (m), VO2 max (ml/kg/min)] in professional and regional amateur league soccer players and to reveal which of these parameters was a distinctive factor in these athletes.71 professional soccer players (age: 23.66 ± 4.11 years; body height: 1.79 ± 6.99 m; body weight: 76.02 ± 6.76 kg; body fat: 11.59±3.11 %) and 62 regional amateur soccer players (age: 23.63 ±3.77 years; body height: 1.81 ± 5.77 m; body weight: 76.36 ± 7.53 kg; body fat: 15.60±4.65 %) volunteered for the study. After DNA extraction from buccal epithelial cells via a commercial kit was performed for the genetic background of the athletes, Real-Time PCR was carried out for genotyping. Furthermore, Yo-Yo IRT1 test was performed to determine the aerobic performance of the soccer players. SPSS 23 (SPSS Inc., Chicago, IL, USA) package program was used for the statistical analysis of the data obtained in the tests. Shapiro-Wilk test for normality and Levene's test for homogeneity of variance were performed. Chi-Square, Independent Sample T Test and One Way ANOVA test were used in the analysis of the parameters. Statistical significance was set as p0.05); however, there was a statistical significance in favor of professional soccer players in terms of aerobic parameters (p<0.05). Consequently, it can be said that aerobic performance is the distinguishing factor, not the ACTN3 gene, in soccer players.

El objetivo de este estudio fue revelar las diferencias entre el genotipo ACTN3 (RR, RX, XX) y el rendimiento aeróbico [Yo-Yo IRT1 (m), VO2 max (ml/kg/min)] en jugadores de fútbol de ligas profesionales y amateurs regionales y determinar cuál de estos parámetros es un factor distintivo en estos deportistas. 71 futbolistas profesionales (edad: 23,66 ±4,11 años; altura corporal: 1,79 ± 6,99 m; peso corporal: 76,02 ± 6,76 kg; grasa corporal: 11,59±3,11 %) y 62 jugadores de fútbol amateur regionales (edad: 23,63 ± 3,77 años; altura corporal: 1,81 ± 5,77 m; peso corporal: 76,36 ± 7,53 kg; grasa corporal: 15,60 ± 4,65 %) se ofrecieron como voluntarios para el estudio. Después de realizar la extracción de ADN de las células epiteliales orales mediante un kit comercial para obtener los antecedentes genéticos de los atletas, se llevó a cabo una PCR en tiempo real para el genotipado. Además, se realizó la prueba Yo-Yo IRT1 para determinar el rendimiento aeróbico de los futbolistas. Para el análisis estadístico de los datos obtenidos en las pruebas se utilizó el programa SPSS 23 (SPSS Inc., Chicago, IL, EE. UU.). Se realizó la prueba de normalidad de Shapiro- Wilk y la prueba de homogeneidad de la varianza de Levene. En el análisis de los parámetros se utilizaron Chi-cuadrado, prueba T para muestra independiente y prueba ANOVA unidireccional. La significancia estadística se estableció en p0,05); sin embargo, hubo significación estadística a favor de los futbolistas profesionales en cuanto a los parámetros aeróbicos (p<0,05). En consecuencia, se puede decir que el rendimiento aeróbico es el factor distintivo, no el gen ACTN3, en los jugadores de fútbol.

Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players / Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. y Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-17. El objetivo de este estudio fue describir un perfil antropométrico, aeróbico y de potencia muscular de basquetbolistas juveniles costarricenses según sexo, posiciones de juego y categoría de edad. Se evaluaron 99 jugadores juveniles (43 mujeres y 56 hombres; 18 bases, 51 aleros y 30 pívots; 42 categoría U16 y 57 categoría U18) de ocho equipos diferentes. La experiencia deportiva de los jugadores fue de 6.5 ± 3.1 años. Se realizaron las siguientes evaluaciones: altura, peso, índice de masa corporal, masa músculo-esquelética, porcentaje de grasa, prueba de contramovimiento (CMJ) y prueba de Yo-Yo de Recuperación Intermitente Nivel I. Los principales resultados mostraron valores significativamente mayores en hombres que en mujeres en peso, talla, masa músculo-esquelética, distancia recorrida en la prueba Yo-Yo, en el VO2max, altura en el CMJ y en el tiempo de vuelo. El porcentaje de grasa fue mayor en mujeres que en hombres. Los jugadores pívots presentaron significativamente mayor estatura, peso corporal y porcentaje de grasa que las otras posiciones de juego. Los bases y los aleros cubrieron más metros en la prueba Yo-Yo y tuvieron mayor VO2máx que los pívots. Entre las categorías U16 y U18 no se encontraron diferencias significativas en ninguna variable. Modelos de regresión mostraron la influencia del peso, porcentaje de grasa corporal, masa músculo esquelética y la edad sobre el VO2máx y CMJ. Como conclusión, según el sexo y las posiciones de juego de los jugadores, estos indicadores variaron. Además, esta información será útil para procesos de promoción, desarrollo y diseño de entrenamientos de baloncesto juvenil en Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. e Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-17. Este estudo teve como objetivo descrever um perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica segundo o sexo, as posições de jogo e a categoria de idade. Foram avaliados 99 jogadores juvenis (43 mulheres e 56 homens; 18 armadores, 51 alas e 30 pivôs; 42 na categoria U16 e 57 na categoria U18) de oito equipes diferentes. A experiência esportiva dos jogadores foi de 6,5 ± 3,1 anos. Foram realizadas as seguintes avaliações: altura, peso, índice de massa corporal, massa musculoesquelética e porcentagem de gordura, teste de salto com contramovimento (SCM) e teste de Yo-Yo de Recuperação Intermitente Nível I. Os principais resultados mostraram valores significativamente maiores em homens do que em mulheres com relação ao peso, tamanho, massa muscular esquelética, distância percorrida no teste Yo-Yo, VO2max, altura no SCM e no tempo de voo. A porcentagem de gordura foi maior em mulheres do que em homens. Os jogadores pivôs apresentaram significativamente maior estatura, peso corporal e porcentagem de gordura do que as outras posições de jogo. Os armadores e os alas cobriram mais metros no teste Yo-Yo e tiveram maior VO2max do que os pivôs. Entre as categorias U16 e U18 não foram encontradas diferenças significativas em nenhuma variável. Modelos de regressão mostraram a influência do peso, da porcentagem de gordura corporal, da massa musculoesquelética e da idade no VO2max e SCM. Conclui-se, portanto, que esses indicadores variam segundo o sexo e as posições dos jogadores. Além disso, essa informação será útil para processos de fomentação, desenvolvimento e desenho de treinamentos de basquete juvenil na Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. & Rojas-Valverde, D. (2022). Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-17. The purpose of this study was to describe an anthropometric, aerobic and muscle power profile of young Costa Rican basketball players according to sex, play positions and age. The assessment was carried outa on 99 young players (43 women and 56 men; 18 guards, 51 forwards and 30 centers; 42 in the U16 category and 57 in the U18 category) from eight different teams. The sports experience of the players was 6.5 ± 3.1 years. The following parameters were assessed: height, weight, body mass index, skeletal muscle mass and body fat percentage, countermovement test (CMJ) and Yo-Yo Intermittent Recovery Test Level I. The main results showed significantly higher values in men than in women in terms of weight, height, skeletal muscle mass, distance covered in the yo-yo test, VO2max, height in CMJ and in flight time. Body fat percentage was higher in women than in men. Centers showed significantly higher height, weight and body fat percentage than other play positions. Guards and forwards covered more meters in the yo-yo test and showed higher VO2max than centers. No significant differences were found between the U16 and U18 categories in any variable. Regression models showed the influence of weight, body fat percentage, skeletal muscle mass and age on VO2max and CMJ. In conclusion, these indicators varied according to the sex and play position of the players. Additionally, this information will be useful for processes of promotion, development and training design of youth basketball in Costa Rica.

Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players / Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. & Rojas-Valverde, D. (2022). Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20(2), 1-15. The purpose of this study was to describe an anthropometric, aerobic and muscle power profile of young Costa Rican basketball players according to sex, play positions and age. The assessment was carried outa on 99 young players (43 women and 56 men; 18 guards, 51 forwards and 30 centers; 42 in the U16 category and 57 in the U18 category) from eight different teams. The sports experience of the players was 6.5 ± 3.1 years. The following parameters were assessed: height, weight, body mass index, skeletal muscle mass and body fat percentage, countermovement test (CMJ) and Yo-Yo Intermittent Recovery Test Level I. The main results showed significantly higher values in men than in women in terms of weight, height, skeletal muscle mass, distance covered in the yo-yo test, VO2max, height in CMJ and in flight time. Body fat percentage was higher in women than in men. Centers showed significantly higher height, weight and body fat percentage than other play positions. Guards and forwards covered more meters in the yo-yo test and showed higher VO2max than centers. No significant differences were found between the U16 and U18 categories in any variable. Regression models showed the influence of weight, body fat percentage, skeletal muscle mass and age on VO2max and CMJ. In conclusion, these indicators varied according to the sex and play position of the players. Additionally, this information will be useful for processes of promotion, development and training design of youth basketball in Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. y Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20(2), 1-15. El objetivo de este estudio fue describir un perfil antropométrico, aeróbico y de potencia muscular de basquetbolistas juveniles costarricenses según sexo, posiciones de juego y categoría de edad. Se evaluaron 99 jugadores juveniles (43 mujeres y 56 hombres; 18 bases, 51 aleros y 30 pívots; 42 categoría U16 y 57 categoría U18) de ocho equipos diferentes. La experiencia deportiva de los jugadores fue de 6.5 ± 3.1 años. Se realizaron las siguientes evaluaciones: altura, peso, índice de masa corporal, masa de músculo esquelética y porcentaje de grasa, prueba de contramovimiento (CMJ) y prueba de Yo-Yo de Recuperación Intermitente Nivel I. Los principales resultados mostraron valores significativamente mayores en hombres que en mujeres en peso, talla, masa muscular esquelética, distancia recorrida en la prueba Yo-Yo, VO2max, altura en el CMJ y en el tiempo de vuelo. El porcentaje de grasa fue mayor en mujeres que en hombres. Los jugadores pívots presentaron significativamente mayor estatura, peso corporal y porcentaje de grasa que las otras posiciones de juego. Los bases y los aleros cubrieron más metros en la prueba Yo-Yo y tuvieron mayor VO2max que los pívots. Entre las categorías U16 y U18 no se encontraron diferencias significativas en ninguna variable. Modelos de regresión mostraron la influencia del peso, porcentaje de grasa corporal, masa músculo esquelética y la edad sobre el VO2max y CMJ. Como conclusión, según el sexo y las posiciones de juego de los jugadores, estos indicadores variaron. Además, esta información será útil para procesos de promoción, desarrollo y diseño de entrenamientos de baloncesto juvenil en Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. e Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20(2), 1-15. Este estudo teve como objetivo descrever um perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica segundo o sexo, as posições de jogo e a categoria de idade. Foram avaliados 99 jogadores juvenis (43 mulheres e 56 homens; 18 armadores, 51 alas e 30 pivôs; 42 na categoria U16 e 57 na categoria U18) de oito equipes diferentes. A experiência esportiva dos jogadores foi de 6,5 ± 3,1 anos. Foram realizadas as seguintes avaliações: altura, peso, índice de massa corporal, massa musculoesquelética e porcentagem de gordura, teste de salto com contramovimento (SCM) e teste de Yo-Yo de Recuperação Intermitente Nível I. Os principais resultados mostraram valores significativamente maiores em homens do que em mulheres com relação ao peso, tamanho, massa muscular esquelética, distância percorrida no teste Yo-Yo, VO2max, altura no SCM e no tempo de voo. A porcentagem de gordura foi maior em mulheres do que em homens. Os jogadores pivôs apresentaram significativamente maior estatura, peso corporal e porcentagem de gordura do que as outras posições de jogo. Os armadores e os alas cobriram mais metros no teste Yo-Yo e tiveram maior VO2max do que os pivôs. Entre as categorias U16 e U18 não foram encontradas diferenças significativas em nenhuma variável. Modelos de regressão mostraram a influência do peso, da porcentagem de gordura corporal, da massa musculoesquelética e da idade no VO2max e SCM. Conclui-se, portanto, que esses indicadores variam segundo o sexo e as posições dos jogadores. Além disso, essa informação será útil para processos de fomentação, desenvolvimento e desenho de treinamentos de basquete juvenil na Costa Rica.

Composición corporal, somatotipo, rendimiento en salto vertical y consumo máximo de oxígeno en futbolistas profesionales y universitarios / Body composition, somatotype, vertical jump performance and maximal oxygen consumption in professional and university soccer players

RESUMEN. Objetivo: El objetivo de este estudio fue describir y comparar la composición corporal, somatotipo, rendimiento en el salto vertical y consumo máximo de oxígeno en futbolistas profesionales y universitarios de Chillán. Metodología:El presente estudio es de tipo transversal, descriptivo y comparativo, con una muestra no probabilística y por conveniencia. Se evaluarona 52 futbolistas varones; 18 corresponden a jugadores profesionales y 34 universitarios. El perfil antropométrico (índice de masa corporal, composición corporal y somatotipo) se obtuvo a través delos protocolos de la Sociedad Internacional para el Avance de la Kinantropometría (ISAK), el consumo máximo de oxígeno (VO2máx) por medio del Yo-Yo test IR1 y capacidad de salto a través del protocolo de Bosco, utilizando una plataforma de contacto Axon Jump.El análisis estadístico se realizó con el programa SPSS v.21;para comparar a ambos grupos se utilizó el estadístico T-Student para muestras independientes (p<0,05). Resultados: Los resultados muestran que los futbolistas profesionales reportanun mayor porcentaje de masa muscular (p<0,001) y un menor porcentaje de masa grasa (p<0,001) en comparación a los universitarios. Los análisis de somatotipo indican que los jugadores profesionales se clasifican como meso-ectomórfico en comparación a los jugadores universitarios, quienes se clasificaron como meso-endomórfico. Finalmente, en cuanto a los resultados en las pruebas físicas los profesionales obtuvieron diferencias significativas en la capacidad de salto (p<0,001) y en el VO2máx (p<0,001).Conclusión: Los futbolistas profesionales tienen características corporales, somatotípicas y físicas que les permiten sobresalir con respecto a los futbolistas universitarios. Estos datos servirán a los entrenadores universitarios para disponer de los parámetros respecto de características y condiciones a trabajar para acercarse al alto rendimiento.

ABSTRACT. Objective: The objective of this study was to describe and compare the body composition, somatotype, vertical jump performance and maximum oxygen consumption in professional and university soccer players from Chillán. Methodology: The present study is cross-sectional, descriptive and comparative, with a non-probabilistic sample and for convenience. 52 male soccer players were evaluated; 18 correspond to professional players and 34 university players. The anthropometric profile (body mass index, body composition and somatotype) was obtained through the International Society for the Advancement of Kinantropometry (ISAK) protocols, the maximum oxygen consumption (VO2 max) by means of the Yo-Yo test IR1 and ability to jump through the Bosco protocol using an Axon Jump contact platform. Statistical analysis was performed with the statistical program SPSS v.21, to compare both groups the T-Student statistic was used for independent samples (p <0.05).Results: The results show that professional soccer players report a higher percentage of muscle mass (p <0.001) and a lower percentage of fatmass (p <0.001) compared to university players. Somatotype analyzes indicate that professional gamers are classified as meso-ectomorphic compared to college players, who are classified as meso-endomorphic. Finally, regarding the results in the physical tests, the professionals obtained significant differences in jumping ability (p <0.001) and in VO2 max (p <0.001).Conclusion: Professional soccer players have bodily, somatotypic and physical characteristics that allow them to stand out comparated to university soccer players. These data will serve university coaches to have the parameters regarding characteristics and conditions to work to approach high performance.

Anthropometric characteristics and physical performance of young elite Kosovo soccer players / Características antropométricas y rendimiento físico de jóvenes futbolistas de élite de Kosovo

The aim of this study was to establish the anthropometric and physical profiles of young soccer players according to their playing position and to determine their relevance for competition success. One hundred and twenty young soccer players participated in the study. Players aged 19 were classified into the following groups: defenders (n=40), midfielders (n=40) and attackers (n=40). The anthropometric variables of participants (height, weight, body mass index, 4 skinfold, 2 diameters, and 2 perimeters) were measured. Also, their somatotype and body composition were calculated. Participants performed Bruce treadmill test protocol and Yo-Yo Intermittent Test to estimate their relative VO2max, sprint tests (5 m and 20 m flat), 2 jump tests (countermovement jump and standing long jump test), 3 tests for assessing agility (Illinois with balls and without balls, and 505-test) and seven fitness tests for assessing power, speed, agility, flexibility, frequency, abdominal muscle power and balance. Analysis of variance (ANOVA) was used to determinate differences between team positions. On the base of the obtained results, it can be established that players playing in midfield position have less body height, weight, and achieve less results in fitness tests Illinois 20-meter running, leg-tapping, sit-ups in 30 seconds, but better results in the tests 'sit and reach', 'flamingo' and the tests of assessing maximum oxygen consumption compared to the defenders and attackers. The attack players have less values in skinfolds and achieve better results in 5-meter running test and standing long jump compared to the midfielders and defenders. The obtained results can serve as normative morphologic-functional indexes for regular medical control of young footballers in the R. Kosovo. They can also be used as a model of comparison of morphologic- functional data between young footballers of similar levels in different countries.

El objetivo de este estudio fue establecer los perfiles antropométricos y físicos de jóvenes futbolistas de acuerdo con su posición de juego y determinar su relevancia para el éxito de la competencia. Ciento veinte jóvenes futbolistas participaron en el estudio. Jugadores de 19 años de edad fueron clasificados en los siguientes grupos: defensores (n = 40), mediocampistas (n = 40) y atacantes (n = 40). Se midieron las variables antropométricas de los participantes (altura, peso, índice de masa corporal, 4 pliegues cutáneos, 2 diámetros y 2 perímetros). Además, se calculó su somatotipo y composición corporal. Los participantes realizaron el protocolo de prueba de cinta de andar de Bruce y la prueba intermitente Yo-Yo para estimar su VO2 máx. relativo, pruebas de velocidad (5 m y 20 m planos), 2 pruebas de salto (contraataque y prueba de salto de pie), 3 pruebas para evaluar la agilidad (Illinois con balones y sin balones, y 505-test) y siete pruebas de condición física para evaluar la potencia, la velocidad, la agilidad, la flexibilidad, la frecuencia, la potencia de los músculos abdominales y el equilibrio. El análisis de varianza (ANOVA) se utilizó para determinar las diferencias entre las posiciones del equipo. Sobre la base de los resultados obtenidos, se puede establecer que los jugadores que juegan en la posición del medio campo tienen menos altura corporal, peso y logran menos resultados en las pruebas de condición física, en comparación con los defensores y atacantes: carrera de 20 metros de Illinois, golpeo de piernas, abdominales en 30 segundos, pero mejores resultados en las pruebas 'sentarse y alcanzar', 'flamingo' y las pruebas de evaluar el consumo máximo de oxígeno. Los jugadores de ataque tienen menos valores en los pliegues cutáneos y logran mejores resultados en una prueba de carrera de 5 metros y en salto largo, en comparación con los centrocampistas y defensores. Los resultados obtenidos pueden servir como índices morfológicos-funcionales normativos para el control médico regular de los jóvenes futbolistas en Kosovo. También pueden usarse como un modelo de comparación de datos morfológico-funcionales entre jóvenes futbolistas de niveles similares en diferentes países.

Correlation between Match Performance and Field Tests in Professional Soccer Players.

The aim of this study was to investigate possible correlations between aerobic and anaerobic fitness (in field tests) with performance during a 90 min friendly match, through the following variables: total distance covered, maximal running speed, number of high-intensity actions and number of sprints. Eighteen professional soccer players from a Brazilian elite team (age 23 ± 3 years, body mass 77.5 ± 8.9 kg) participated in the study. The athletes performed a Yo-Yo Endurance Test (aerobic fitness) and a Running Anaerobic Sprint Test (six maximal 35 m efforts separated by 10 s of passive recovery, anaerobic fitness). Data were collected during friendly matches using a GPS with 5 Hz technology. To establish the correlation between the variables determined during the matches, the Pearson correlation coefficient was used (significance level of p ≤ 0.05). A high correlation was found between distance covered in the Yo-Yo endurance test and total distance covered (r = 0.72; p < 0.05), number of high-intensity actions (r = 0.78; p < 0.05) and number of sprints (r = 0.88; p < 0.01) in the soccer matches. The RAST variables did not relate to the standards set during the matches (p < 0.05). From the results of the present study, it may be concluded that there is no correlation between RAST and friendly match data variables. However, better results in the Yo-Yo endurance test correlate with total distance, number of high-intensity actions and sprints during matches.

Six weeks of ß-alanine supplementation did not enhance repeated-sprint ability or technical performances in young elite basketball players.

Supplementation with ß-alanine plays an important role as a precursor of carnosine, the most effective intramuscular buffer, and has been seen as a potential ergogenic aid, especially for high-intensity modalities such as basketball. Thus, the aim of the present study was to investigate the effects of 6 weeks of ß-alanine supplementation on repeated sprint ability (RSA) and technical performances in young elite Brazilian basketball players. In total, 27 young basketball players (17±1 years) were randomized into a ß-alanine group (Gß - 6.4 g day-1 of ß-alanine) and a placebo group (GP - 6.4 g day-1 of dextrose). Before and after the supplementation period the athletes performed a RSA test composed of ten 30 m sprints with two 180° changes of direction interspaced by 30 s of recovery. During the recovery period (i.e., after the sprints) the athletes performed a countermovement jump (CMJ) and a set of three free throws. After 48 h they performed a Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1). Both groups increased the distance covered in the Yo-Yo IR1 after the supplementation period ( p = 0.001). On the other hand, both groups presented impairment in RSA time-performance (total time, best time, and mean time, p ≤ 0.04), while no significant changes were observed for technical task performances (i.e., CMJ and free throws) ( p ≥ 0.07). No between-group interactions were observed for any variable measured ( p ≥ 0.31). Thus, 6 weeks of ß-alanine supplementation did not improve RSA or technical performances in young elite basketball players.

Perfil cardiorrespiratório entre atacantes e defensores de uma equipe profissional de rugby / Aerobic Profile Between Backs And Forwards Of Professional Rugby

O Rugby caracteriza-se como um desporto competitivo, normalmente praticado por 15 jogadores em cada equipe. É um esporte que exige ao extremo as aptidões físicas, contendo corridas em altas velocidades, colisões físicas entre os atletas e grande potência muscular (explosão muscular). O Yoyo test consiste na execução de exercícios intermitentes realizados, aumentando progressivamente a velocidade, intercaladas com 10 segundos de períodos de descanso ativo e executadas até que o sujeito esgotar-se, com intuito de avaliar a capacidade aeróbica dos mesmos.. O presente estudo teve como objetivo aferir através do protocolo de teste yo-yo o nível de VO2 máximo estimado de jogadores de rugby da região metropolitana da cidade do Rio de Janeiro. Participaram do estudo 25 jogadores do sexo masculino com idade de 24,16 ± 6,35 anos, massa corporal 80 ± 9,2 kg e, estatura de 1,79 ± 5,6 m. Todos os avaliados realizaram três sessões do Yo Yo teste nível 1 com intervalo de 72 horas entre as sessões obtendo uma média para o grupo de 45,25 ± 3,8 ml*kg*min-1 de VO2 máximo, sendo 47,7 ml*kg*min-1 para os Forwards (defensores) e 42,3 ml*kg*min-1 para os Backs (atacantes). Na análise descritiva foram calculadas as médias e desvio-padrão das variáveis. O teste de Shapiro-Wilk determinou que os dados são paramétricos O teste t pareado foi aplicado para comparar o distancia media e VO2 Maximo estimado no teste yo-yo entre defensores e atacantes. A análise estatística foi realizada no software SPSS 20.0 e para todas as analises foi adotado o valor de p < 0,05. Em conclusão, pode verificar que o grupo de defensores, apesar de, possuírem maior massa corporal e maior estatura, apresentou melhor aptidão cardiorrespiratória quando comparado ao grupo de atacantes. Quando analisado a distância total percorrida após os testes o resultado também foi superior no grupo dos defensores.(AU)

Rugby is characterized for a competitive sport usually played by 15 subjects on each team. It is a sport that requires the extreme physical skills, containing short running at high speeds, physical collisions between athletes and great muscle power (muscle power). The Yo-yo test consists on execute out intermittent exercise performed progressively increasing speed, active rest with 10 seconds and executed until the subject was exhausted, designed to evaluate aerobic profile. This study aimed to assess by testing protocol yoyo level one VO2 maximum rugby players in the metropolitan region of Rio de Janeiro city. The study included 25 male players aged 24.16 ± 6.35 years, body mass 80 ± 9.2 kg, height 1.79 ± 5.6M. All reviews conducted three sessions of Yo Yo test level 1 with an interval of 72 hours between sessions getting an average for the group of 45.25 ± 3.8 ml*kg*min-1 to VO2 max kg.min, and 47. ml*kg*min-1 for forwards (defenders) and 42.3 ml*kg*min-1 to Backs (attackers). In the descriptive analysis the mean and standard deviation of the variables were calculated. The Shapiro-Wilk test determined that the data are parametric the paired t test was used to compare the average distance and VO2 Max estimated in the yo-yo test between defenders and attackers. Statistical analysis was performed using SPSS 20.0 software and for all analyzes was adopted p value <0.05. Found that forwards group, although their bigger body mass and stature, had a better aerobic profile when compared to the backs groups. When analyzing the total distance traveled after the test was higher in the group of defenders.(AU)

Autonomic correlates of Yo-Yo performance in soccer referees / Correlatos autonômicos do desempenho no Yo-Yo em árbitros de futebol

We tested the hypothesis that: basal cardiac autonomic modulation (i.e. heart rate variability, HRV) was associated with the parasympathetic withdrawal during, and overall Yo-Yo IR1 performance; and therefore HRV could be used as a simple tool for specific fitness assessment. Nine sub-elite soccer referees performed the Yo-Yo IR1 until exhaustion with simultaneous recording of heart rate with the autonomic response during exercise calculated as the area under the curve (AUC). In the same week but with at least 48 hrs between days, a night-time HR recording was obtained from participants for determination of basal HRV. Correlation analysis demonstrated strong (r>0.83) relationships among Yo-Yo IR1 performance, AUC and basal HRV. These results indicate that both nocturnal HRV and AUC can be utilised as simple and valid monitoring tools of soccer referees' fitness.

Nós testamos a hipótese de: que a modulação autonômica cardíaca (i.e. variabilidade da freqüência cardíaca, VFC) está associada com a retirada parassimpática durante a execução do Yo-Yo IR1; e que, portanto, a VFC poderia ser usada como uma ferramenta simples para a avaliação do desempenho físico específico. Nove árbitros sub-elite de futebol executaram o Yo-Yo IR1 até a exaustão com registro simultâneo da freqüência cardíaca e VFC para o cálculo da área sob a curva (ASC). Na mesma semana, mas com mínimo de 48 horas entre dias, obteve-se um registro noturno da FC dos participantes para a determinação da VFC basal. As análises de correlação demonstraram elevados coeficientes (r>0,83) entre o desempenho no Yo-Yo IR1, a ASC e a VFC basal. Estes resultados indicam que a VFC noturna e a ASC podem ser empregadas como ferramentas simples e válidas para o monitoramento do desempenho de árbitros de futebol.