Condición física de futbolistas adultos y jóvenes de un equipo profesional de Nicaragua / Condição física de jogadores de futebol adultos y juniores de uma equipe profissional na Nicaragua / Physical condition of adult and junior soccer players of a professional team in Nicaragua

En la actualidad, el fútbol es un deporte que demanda un alto desempeño físico, por lo que conocer las características de la condición física en las distintas categorías de desarrollo se hace fundamental para conducir un óptimo proceso de entrenamiento, de modo que, el objetivo de este estudio es evaluar la condición física de futbolistas de un club profesional de Nicaragua, según la categoría de edad en las cuales se desempeñaban. El presente es un estudio de tipo descriptivo, comparativo, de la condición física de 187 futbolistas, de edades entre 13 y 31 años, distribuidos por categoría según año de nacimiento y plantel profesional. El grupo PRO presenta mayor rendimiento en comparación a las categorías U13, U15, U17 y U21 (p < 0,001) en tiempo sprint lineal 10 metros (F = 71 y TE = 0,71), 30 metros (F = 85 y TE = 0,70), velocidad de tiro (F = 171 y TE = 0,81), Tiempo en test agilidad de Illinois (F = 77 y TE = 0,72) y metros recorridos en Yo-Yo de recuperación intermitente nivel 1 (F = 121 y TE = 0,73). Se puede concluir que existe un mayor rendimiento de los aspectos físicos por parte de las categorías de mayor edad. Estos resultados pueden servir de referencia o de parámetros de comparación de rendimiento físico de jugadores jóvenes y adultos a nivel nacional de Nicaragua.

Currently, soccer is a sport that demands high physical performance, so knowing the characteristics of the physical condition of players in the different categories of development is essential for conducting an optimal training process. Thus, the objective of this study is to evaluate the physical condition of soccer players from a professional club in Nicaragua, according to the age category in which they played. This is a descriptive and comparative study of the physical condition of 187 soccer players between the ages of 13 and 31, distributed by category, according to year of birth and the professional team they were on. The PRO group presented higher performance in comparison to the U13, U15, U17, and U21 categories (p<0.001) in the 10 meters linear sprint time (F=71 and TE=0.71), 30 meters linear sprint time (F=85 and TE=0.70), shooting speed (F=171 and TE=0.81), time in Illinois agility test (F=77 and TE=0.72), and in meters ran in the Yo-Yo intermittent recovery level 1 (F=121 and TE=0.73). The study shows that there is a higher performance of the older categories in the physical aspects. These results can serve as reference or comparison parameters of the physical performance of young and adult players at a national level in Nicaragua.

Atualmente, o futebol é um esporte que exige um alto desempenho físico, portanto, conhecer as características da condição física nas diferentes categorias de desenvolvimento é essencial para conduzir um processo de treinamento ideal, portanto, o objetivo deste estudo é avaliar a condição física dos jogadores de futebol de um clube profissional na Nicarágua, de acordo com a categoria etária em que jogaram. Este é um estudo descritivo e comparativo da condição física de 187 jogadores de futebol entre 13 e 31 anos, distribuídos por categoria de acordo com o ano de nascimento e equipe profissional. O grupo PRO apresentou melhor desempenho em comparação com as categorias U13, U15, U17 e U21 (p<0,001) em tempo de sprint linear 10 metros (F=71 e TE=0.71), 30 metros (F=85 e TE=0,70), velocidade de tiro (F=171 e TE=0.81), tempo em teste de agilidade illinois (F=77 e TE=0.72) e metros corridos em Yo-Yo de nível de recuperação intermitente 1 (F=121 e TE=0.73). Pode-se concluir que há um maior desempenho dos aspectos físicos por parte das categorias mais antigas. Estes resultados podem servir como parâmetros de referência ou comparação do desempenho físico de jogadores jovens e adultos a nível nacional na Nicarágua.

Can the Supido Radar Be Used for Measuring Ball Speed during Soccer Kicking? A Reliability and Concurrent Validity Study of a New Low-Cost Device.

The aim was to analyze the reliability and validity of a low-cost instrument, based on a radar system, to quantify the kicking ball speed in soccer. A group of 153 male soccer players (under-13, n = 53; under-15, n = 54; under-18, n = 46) participated in this study. Each player performed three kicks on the goal in a standardized condition while the ball speed was measured with three different devices: one Radar Stalker ATS II® (reference criterion) and two Supido Radar® (Supido-front of the goal and Supido-back of the goal). The standard error of measurement (SEM) expressed as a coefficient of variation (CV) and the intraclass correlation coefficient (ICC) were employed for assessing the reliability of each instrument. Stalker and Supido-back showed very high absolute (CV = 4.0-5.4%) and relative (ICC = 0.945-0.958) reliability, whereas Supido-front resulted in moderate to low reliability scores (CV = 7.4-15%, ICC = 0.134-0.693). In addition, Lin's concordance correlation coefficient (CCC) values revealed an 'almost perfect' agreement between Stalker and Supido-back for the average (r = 0.99) and maximal (r = 0.98) ball speed, regardless of the ball speed range analyzed. However, Supido-front resulted in a poor degree of concordance (CCC = 0.688) and a high magnitude of error (17.0-37.5 km·h-1) with the reference Stalker radar gun. The Supido Radar® placed behind the goal could be considered a reliable and valid device for measuring ball speed in soccer.

Diferencias de carga interna y externa entre futbolistas adultosy juveniles en un partido amistoso / Differences in internal and external load between adult and youth players in a friendly match

Objetivo: Determinar diferencias de carga interna y externa durante un partido no-oficial entre jugadores de Primera División Adultos y Sub-19 del mismo club empleando sistemas portátiles de posicionamiento global. Método: Durante un partido no-oficial entre una categoría Adulta y una Sub-19, se monitoreó la carga interna a través de la frecuencia cardíaca y carga externa a través del rendimiento de carrera. Se monitorearon a siete jugadores adultos (25,57 ± 5,06 años) y cinco jugadores Sub-19 (18,6 ± 0,54 años). Se realizaron comparaciones entre las categorías en el primer tiempo, segundo tiempo y partido total mediante la prueba U de Mann-Whitney y calculando los tamaños del efecto a través de porcentajes de diferencia (PD). Resultados: Se encontraron diferencias (p<0,05) de carga externa en velocidad máxima en primer tiempo y partido total, alcanzando los jugadores Sub-19 los valores más elevados (velocidad máxima primer tiempo: 32,34 vs 27,77 km/h y PD = 15,3%; partido total: 32,6 vs 28,14 km/h y PD = 14,7%). Por otro lado, solo se hallaron diferencias en carga interna en zona 3 de frecuencia cardíaca (70 a 80% de la FC máxima) en primer y segundo tiempo, donde los jugadores Sub-19 pasaron más tiempo en esta zona (zona 3 de frecuencia cardiaca primer tiempo: 6,1 vs 1,73 minutos y PD = 111,6%; segundo tiempo: 20,49 vs 5,21 minutos y PD = 118,8%). No se hallaron diferencias en las demás variables analizadas. Conclusión: A partir de los resultados obtenidos podemos concluir que no existen diferencias de carga interna y externa en jugadores adultos con jugadores sub-19, con excepción de velocidad máxima y zona 3 de frecuencia cardiaca en este equipo durante un partido no oficial. Por lo que, para efectos prácticos, los jugadores Sub-19 de este equipo, podrían encontrarse en condiciones para enfrentar las exigencias físicas que requiere la competencia de categoría adulta.(AU)

Objective: To determine differences in internal and external load during an unofficial match between First Division Adult and U-19 players of the same club using portable global positioning systems. Methods: During an unofficial match between an adult and a U-19 category, internal load through heart rate and external load through running performance were monitored. Seven adult players (25.57 ± 5.06 years) and five U-19 players (18.6 ± 0.54 years) were monitored. Comparisons were made between categories in the first half, second half and total match using the Mann-Whitney U test and calculating effect sizes through percent difference (PD). Results: Differences were found (p<0.05) of external load in maximum speed in first half and total match, with U-19 players reaching the highest values (maximum speed first half: 32.34 vs 27.77 km/h and PD = 15.3%; total match: 32.6 vs 28.14 km/h and PD = 14.7%). On the other hand, differences in internal load were only found in heart rate zone 3 (70 to 80% of maximum HR) in the first and second half, where U-19 players spent more time in this zone (heart rate zone 3 first half: 6.1 vs 1.73 minutes and PD = 111.6%; second half: 20.49 vs 5.21 minutes and PD = 118.8%). No differences were found in the other variables analyzed. Conclusion: From the results obtained we can conclude that there are no differences in internal and external load in adult players with U-19 players, except for maximum speed and heart rate zone 3 in this team during a non-official match. Therefore, for practical purposes, the U-19 players of this team could be in conditions to face the physical demands required by the adult category competition.(AU)

Relationship between Physical Fitness and Match Performance Parameters of Chile Women's National Football Team.

The aim of this study was to analyze the relationships between the level of physical fitness and the physical performance parameters recorded by GPS in official FIFA matches of the Chilean women's senior national football team in the period 2018-2020. Twenty-six female field players (age (mean ± SD) 26.8 ± 3.3 years, height 157.8 ± 21.5 cm, weight 58.9 ± 4.9 kg) participated in the study. Physical fitness variables were assessed: muscular strength, countermovement jump (CMJ), speed, agility and aerobic fitness. Physical performance variables were recorded by GPS in 26 official FIFA matches. The most notable associations with significant statistical significance (p < 0.001) were those observed between neuromuscular variables such as time to run 10 m (T10; r = -0.629) and jump (CMJ; r = 0.502) and the number of accelerations; aerobic fitness showed a highly significant relationship with meters run per minute (M/M; r = 0.589). The findings of this study provide evidence of how the level of physical fitness (neuromuscular and aerobic) relates to physical performance parameters recorded in official competitions.

Acute Effects on Physical Performance Measures after 45 Min of Official Competition in Youth Soccer Players.

(1) Background: An improved understanding of soccer players' match-related physical performance and recovery may help conditioning programs and re-warm up strategies to increase team performance during official competitions. Therefore, the aim of this study was to analyze the acute effects of 45 min of official competition (first half in matches) on physical performance variables in U-16 youth soccer players. (2) Methods: 20 male soccer players (age: 14.4 ± 0.5 years; height: 1.70 ± 0.05 cm; body mass: 65.1 ± 11.6 kg) were recruited to participate in this study. Data was collected from five official matches. Participants performed the assessments in two stages of each match: after the pre-match warm-up and after the first half. Tests included rate of perceived exertion (RPE), 30-m sprint and countermovement (CMJ). (3) Results: Statistically significant differences were found (p < 0.001) when the measurements prior to the game were compared with those recorded after half time across all variables. Effect sizes (ES) were very large for RPE (ES = 1.82), moderate for 30-m sprint times (ES = 0.64) and small for CMJ (ES = -0.25). (4) Conclusions: After 45 min of official competition, our results suggest that U-16 soccer players demonstrated a reduction in sprint and jump performance, in addition to a higher RPE. Hence, this information could be useful when designing re-warming strategies that can be performed before the second half.

In-Season Assessment of Sprint Speed and Sprint Momentum in Rugby Players According To the Age Category and Playing Position.

The purpose of this study was to investigate the interval in which male rugby union players reach maximum speed in a 50 m sprint according to age categories and playing positions. This study also aimed to establish the optimal distance for the assessment of sprint speed and to compare the differences in anthropometrics, sprint and sprint momentum according to the age and playing position. Three hundred amateur rugby players performed anthropometric and physical fitness tests (10, 20, 30, 40 and 50 m sprint times, acceleration, velocity, and sprint momentum) during the in-season period. Participants from different age categories (under 14's (U14), under 16's (U16), under 18's (U18) and Seniors) and positions (forwards and backs) volunteered to participate in this study. Results revealed that most of the U14 and U16 players (58.2% and 55.3%, respectively) reached maximum speed in the interval between 20 and 30 m with lower sprint speed than U18 players and Seniors (44% and 49%, respectively). Comparisons between each interval showed significant differences for all U14 and U16 forwards, suggesting the fastest interval was between 20-30 m. No significant differences were found for U16 backs, U18 and Seniors, between sprint times in the 20-30 m and 3040 m intervals. In addition, between-group comparisons, demonstrated significant (p < 0.001) differences in U14 when compared to U16, U18 and Seniors in anthropometric variables, sprint times and sprint momentum. In conclusion, this study suggests that the optimal distance for the assessment of sprint speed of rugby players is 30 m and that body mass, sprint momentum and sprint speed clearly discriminate between players of different age categories and playing positions.

Effects of COVID-19 confinement measures on training loads and the level of well-being in players from Chile women's national soccer team / Efectos de las medidas de confinamiento por COVID-19 en el grado de bienestar y la carga de entrenamiento de las jugadoras de la selección nacional de fútbol de Chile

Abstract Introduction: Due to the current COVID-19 pandemic, many countries have implemented control and prevention measures, such as compulsory lockdowns, affecting all spheres of life. Since the field of professional soccer is no exception, such measures may have a negative impact on the player's well-being and their perceived training loads. Objective: To determine the impact of COVID-19 lockdown measures on the training load and the well-being of female professional soccer players in Chile. Materials and methods: Exploratory, cross-sectional, descriptive study conducted on 32 players of the Chile women's national soccer team. The perception of training load and the level of well-being were assessed by means of the rating of perceived exertion (RPE) scale and a questionnaire developed in 2010, respectively. Both the administration of the questionnaire and the permanent monitoring of the RPE records were carried out in two periods of 12 weeks: regular preparatory phase (12/12/2019-10/03/2020) and lockdown (16/03/2020-07/06/2020). Data were analyzed using descriptive statistics and the Wilcoxon test was used to determine if there were significant differences between periods. Results: Significant differences (p<0.05) and threshold effect sizes (ES)=1.2, 2.0 and 4.0 (large, very large, and extremely large, respectively) were found between both periods in all variables evaluated by the well-being questionnaire (except for sleep quality): muscle soreness and stress level (ES=1.9), perceived fatigue (ES=2.5), general well-being (ES=2.4), and mood (ES=4.2). No differences were found regarding the perception of the training load (ES=0.1) between both periods. Conclusions: The level of well-being among the participants was negatively affected by the compulsory lock-down. Therefore, coaching staffs should continue to monitor the level of the well-being of professional soccer players during the lockdown, both individually and collectively. Even though the perception of training load was not affected, it is not possible to state that a more extended period of confinement will not reduce it, resulting in a drop in performance.

Resumen Introducción. Debido a la actual pandemia por COVID-19, muchos países tomaron medidas de control y prevención como el confinamiento obligatorio, afectando todas las esferas de la vida. Ya que los futbolistas profesionales no son una excepción, este tipo de medidas puede tener un impacto negativo en su bienestar y en su percepción sobre las cargas de entrenamiento. Objetivo. Determinar los efectos de las medidas de confinamiento por COVID-19 en la carga de entrenamiento y el grado de bienestar de jugadoras de fútbol profesional de Chile. Materiales y métodos. Estudio transversal, exploratorio-descriptivo realizado en 32 jugadoras de la Selección Nacional de Fútbol de Chile. El grado de bienestar y la carga de entrenamiento se evaluaron mediante un cuestionario desarrollado en 2010 y mediante la escala de percepción subjetiva del esfuerzo (PSE) y el volumen de entrenamiento expresado en minutos, respectivamente. Ambas evaluaciones se realizaron en 2 periodos de 12 semanas : periodo preparatorio regular (12/12/2019-10/03/2020) y periodo de confinamiento (16/03/2020-07/06/2020). Los datos se analizaron mediante estadística descriptiva y la prueba de Wilcoxon se utilizó para determinar si hubo diferencias significativas entre ambos periodos. Resultados. Se encontraron diferencias significativas (p<0.05) y umbrales de tamaño del efecto (TE) iguales a 1.2, 2.0 y 4.0 (grande, muy grande y extremadamente grande, respectivamente) entre ambos periodos en todas las variables evaluadas por el cuestionario de bienestar (a excepción de calidad de sueño): dolor muscular y nivel de estrés (TE=1.9), fatiga percibida (TE=2.5), bienestar general (TE=2.4) y estado de ánimo (TE=4.2). No se observaron diferencias en la PSE (TE=0.1) entre ambos periodos. Conclusiones. El confinamiento obligatorio afectó negativamente el grado de bienestar de las participantes, por lo que es necesario que los cuerpos técnicos monitoreen constantemente, de manera individual y colectiva, el grado de bienestar de los futbolistas profesionales durante estos periodos; si bien la percepción en la carga de entrenamiento no se vio afectada, no es posible asegurar que un periodo mayor de confinamiento no la disminuya y esto resulte en una baja del rendimiento.