Effects of bout duration on players internal and external loads during small-sided games in soccer

The evolution observed in soccer over the last years has led to an increase in the physical and metabolic demands required during a game. To prepare players for these demands, coaches must prescribe high-intensity training stimuli, which follow the modern competition's requirements. Thus, selecting the appropriate form, duration, and recovery time of exercises, with the objective of controlling training load, is regarded as a task of vital importance for the enhancement and development of capacities during the training process. Therefore, the general objective of this thesis was to identify which form, duration, and recovery time of a specific training exercise allowed male soccer players to reach and maintain higher training loads. To achieve the proposed objectives, the following sequence of work was conducted: (i) review of the literature on the proposed theme, (ii) comparison between the use of the continuous method or the fractionated method in the training load during the performance of small-sided games, and (iii) assessment of the impact of different recovery times on training load during small-sided games. The main evidence suggests that (i) exercises performed by the fractionated training method induce greater responses at the level of external load when compared to exercises performed by the continuous method; (ii) during the performance of small-sided games, the increase in the number of repetitions of the exercise (fractionated method) induces increases in the external load variables compared to the use of the continuous method; (iii) different recovery times for the same total exercise duration, induced differences in internal and external loads; iv) short recovery periods (i.e. 30 s) were sufficient to maintain high training loads compared to longer recovery periods (i.e. 1-2 min) during the performance of 5-a-side small-sided games v) the fractionated method should be used if the trainer aims to induce high training loads during 5-a-side small-sided games, since the continuous method seems to have caused a decrease in the players physical and physiological responses. This thesis also allows the development of guidelines for the prescription and monitoring of training load in soccer, using small-side games.A evolução verificada durante os últimos anos no futebol, levou ao aumento das solicitações físicas e metabólicas requeridas durante um jogo. De modo a prepararem as equipas para estas exigências, os treinadores devem prescrever estímulos de treino de alta intensidade, que acompanhem a exigência da competição. Assim, a escolha adequada da forma, duração e tempo de recuperação do exercício, com o objetivo de controlar a carga de treino, assumem-se como tarefas de vital importância para a potenciação e desenvolvimento das capacidades durante o processo de treino. Consequentemente, o objetivo geral desta tese foi identificar de que forma, a duração e o tempo de recuperação de um exercício específico de treino permitem atingir e manter cargas de treino mais elevadas em jogadores de futebol masculino. De modo atingir os objetivos propostos foi utilizada a seguinte sequência de trabalho: (i) revisão da literatura sobre o tema proposto, (ii) comparação entre a utilização do método continuo ou do método fracionado na carga de treino durante a realização de jogos reduzidos, (iii) impacto de diferentes tempos de recuperação na carga de treino durante a realização de jogos reduzidos. As principais evidências sugerem que: (i) exercícios realizados pelo método de treino fracionado induziram maiores respostas ao nível da carga externa quando comparados aos exercícios realizados pelo método contínuo; (ii) distintos tempos de recuperação para a mesma duração total do exercício, induziram diferenças nas respostas de cargas interna e externa de treino; iii) períodos curtos de recuperação (i.e., 30 s) foram suficientes para manter elevadas as cargas de treino em comparação com períodos de recuperação mais longos (i.e., 1-2 min) durante o desempenho de jogos reduzidos no formato 5 contra cinco iv) o método fracionado deve ser usado se o treinador tiver como objetivo induzir elevadas cargas de treino durante jogos reduzidos de 5 contra 5. Esta tese permite, igualmente, o desenvolvimento de diretrizes para a prescrição e monitorização da carga de treino no futebol através do uso de jogos reduzidos.La evolución observada durante los últimos años en el fútbol ha llevado a un aumento en las demandas físicas y metabólicas requeridas durante una partida. Para preparar a los equipos para estas demandas, los entrenadores deben prescribir estímulos de entrenamiento de alta intensidad, que acompañan el requisito de la competición. Así, la elección adecuada de la forma, duración y tiempo de recuperación del ejercicio, con el objetivo de controlar la carga de entrenamiento, se asume como misión de vital importancia para la potenciación y desarrollo de las capacidades durante el proceso de entrenamiento-. Así, el objetivo general de esta tesis fue identificar qué forma, duración y tiempo de recuperación de un ejercicio de entrenamiento específico permitió alcanzar y mantener cargas de entrenamiento más altas en jugadores de fútbol masculino. Para lograr los objetivos propuestos, se utilizó la siguiente secuencia de trabajo: (i) revisión de la literatura sobre el tema propuesto, (ii) comparación entre el uso del método continuo o el método fraccional en la carga de entrenamiento durante la ejecución de juegos reducidos, (iii) impacto de diferentes tiempos de recuperación en la carga de entrenamiento durante juegos reducidos. La evidencia principal sugiere que: (i) los ejercicios realizados por el método de entrenamiento fraccionado inducen mayores respuestas a nivel de carga externa en comparación con los ejercicios realizados por el método continuo; (ii) diferentes tiempos de recuperación para la misma duración total del ejercicio, indujeron diferencias en las cargas internas y externas; iii) los períodos de recuperación cortos (i.e., 30 s) fueron suficientes para mantener altas cargas de entrenamiento en comparación con los períodos de recuperación más largos (i.e., 1-2 min) durante la ejecución de juegos de 5 contra 5 en espacios reducidos iv) se debe utilizar el método fraccionado si el entrenador tiene como objetivo inducir cargas elevadas de entrenamiento durante el juego de 5 contra 5 en espacios reducidos. Esta tesis también permite el desarrollo de pautas para la prescripción y monitoreo de la carga de entrenamiento en el fútbol mediante el uso de juegos reducidos

SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal

Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal. Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team, IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation (https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing guidance on the implementation of the phylodynamic models; Joshua L. Cherry (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health) for providing guidance with the subsampling strategies; and all authors, originating and submitting laboratories who have contributed genome data on GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions expressed in this article are those of the authors and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info:eu-repo/semantics/publishedVersio

Caracterização do perfil físico em jovens jogadores de futebol de acordo com a especificidade posicional

O propósito deste estudo foi comparar as características físicas e antropométricas de jovens jogadores de futebol com diferentes posições de jogo. Para além disso foi também investigado se existiam diferenças entre os escalões etários (S-14, S-16 e S-18) para as características físicas e antropométricas. A amostra foi constituída por 167 jogadores de futebol jovens que competem a nível nacional nos escalões de sub 14 (S-14), sub 16 (S-16) e sub 18 (S-18), em posições de jogo diferentes, que foram avaliados através de testes antropométricos e de vários testes para avaliação a capacidade física (sprint, remate, lançamento de bola de futebol e salto com contra movimento). As principais conclusões são que existem diferenças antropométricas entre os jogadores que atuam nas posições de DE e DD, uma vez que estes se conotam como sendo mais pequenos do que os AV. Estas diferenças também foram evidenciadas nos testes físicos com os avançados a obterem as melhores performances nos testes de lançamento da bola de futebol, salto com contra movimento e nos testes de sprint (20 e 30m) comparativamente com os jogadores que atuam nas posições de defesa, os defesas direitos por sua vez saltam menos comparativamente com os jogadores que atuam nas posições do meio campo. Concluímos, segundo os resultados que existem diferenças significativas entre as diferentes posições de jogo em jovens jogadores de futebol no que diz respeito as suas características físicas e antropométricas. Desta forma os resultados dão ênfase à importância da definição do perfil de atividade física e ao seu desenvolvimento segundo a idade e a posição de jogo

Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study

We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care