Variação na carga de treinamento de força: Ainda há muito para se explicar

Studies have shown that periodic variations in the strength training configuration are more efficient for promoting muscle strength in comparison to training that does not vary over time. Although the evidences point the superiority of the varied training, it’s not clear how the processes that influence the force production are affected when training is performed using variation through the time. The present study aims to discuss the central and peripheral mechanisms that influence the process of force production and to generate insights for new investigations that aim to compare the strength development between the varied and non-varied strength training programs.Estudios han demostrado que las variaciones periódicas en la carga del entrenamiento de son más efectivas para promover la fuerza muscular en comparación con el entrenamiento que no varía la carga con el tiempo. Esta variación se produce al manipular las variables de un programa de entrenamiento, como la intensidad, el volumen, la velocidad de las acciones musculares y el orden de los ejercicios. Aunque la evidencia apunta a la superioridad del entrenamiento variado, no está claro cómo los procesos que influyen en la producción de fuerza se ven afectados cuando el entrenamiento se realiza con cargas variables. Conocer los mecanismos desencadenados por la variación de la carga puede conducir a un entrenamiento más específico hacia los objetivos deseados. Nuestro objetivo es discutir los mecanismos centrales y periféricos que influyen en el proceso de producción de fuerza y generar conocimientos para nuevas investigaciones que tienen como objetivo comparar el desarrollo de la fuerza entre los programas de entrenamiento de fuerza variados y no variados.Estudos demonstraram que as variações periódicas na carga de treinamento de força são mais eficientes para promover força muscular em comparação a treinamentos que não variam a carga ao longo do tempo. Essa variação ocorre pela manipulação das variáveis de um programa de treinamento, como a intensidade, volume, velocidade das ações musculares e ordem dos exercícios. Embora as evidências apontem a superioridade do treinamento variado, não está claro como os processos que influenciam a produção de força são afetados quando o treinamento é realizado com variação de carga. Conhecer os mecanismos desencadeados pela variação da carga ao longo do tempo pode levar a treinamentos mais específicos aos objetivos desejados. Assim, objetivamos discutir os mecanismos centrais e periféricos que influenciam o processo de produção de força e gerar insights para novas investigações que visem comparar o desenvolvimento da força entre os variados e não variados programas de treinamento de força

Efeito da amplitude de movimento no número máximo de repetições no exercício supino livre

There are divergent results about increases in strength using different ranges of motion (ROM). The aim of this study was to compare the maximum number of repetitions (MNR) in bench press with two different ROM. Fourteen subjects performed familiarization and one repetition maximum (1 RM) tests in sessions 1 and 2. MNR in four sets at 50% of 1 RM, one-minute rest with partial (ROMP) and complete ROM (ROMC) were performed in the third and fourth sessions. The ROMP used half of the bar vertical displacement compared to ROMC. Two-way ANOVA with repeated measures was used to compare the experimental conditions, followed by post hoc Scheffe. There was a significant decrease of the MNR among sets, except from third to fourth sets in both ROM. MNR in all sets was higher in ROMP than ROMC. The reduction of ROM allow to perform higher number of repetitions.Investigaciones cientificas muestran resultados divergentes en el aumento de la fuerza utilizando diferentes amplitudes de movimiento (ADM). El objetivo de este estudio fue comparar el número máximo de repeticiones (NMR) en un ejercicio de supino con dos ADM. Catorce voluntarios realizaron la familiarización y el test de una repetición máxima (1 RM) en las sesiones 1 y 2. En las sesiones 3 y 4 realizaron o NMR en cuatro series a 50% de 1 RM, un minuto de pausa con ADM parcial (ADMP) y completa (ADMC). ADMP utilizó la mitad del desplazamiento vertical de la barra realizado durante la ADMC. Fue aplicada ANOVA "two-way" con medidas repetidas, seguido del "Post hoc" Scheffé. Se encontró disminución significante del NMR a lo largo de las series, excepto de la tercera para la cuarta en ambas ADM, con el mismo patrón de reducción en ambas ADM. El NMR de la ADMP fue mayor que la ADMC. La reducción de ADM interfirió en el volumen de entrenamiento con mayor número de repeticiones realizadas para una misma intensidad relativa.Pesquisas mostram resultados divergentes no aumento da força utilizando diferentes amplitudes de movimento (ADM). O objetivo deste estudo foi comparar o número máximo de repetições (NMR) no exercício supino com duas ADM. Quatorze voluntários realizaram a familiarização e o teste de uma repetição máxima (1 RM) nas sessões 1 e 2. Nas sessões 3 e 4 realizaram o NMR em quatro séries a 50% de 1 RM, com um minuto de pausa, com ADM parcial (ADMP) e completa (ADMC). Na ADMP utilizou-se metade do deslocamento vertical da barra comparada a condição ADMC. Foi realizada ANOVA "two-way" com medidas repetidas, seguida pelo "Post hoc" Scheffé. Houve diminuição significante do NMR entre as séries, exceto da terceira para a quarta em ambas ADM. Um maior NMR foi verificado para ADMP. A redução da ADM permite a realização de um maior número de repetições para uma mesma intensidade relativa

Medical residency in gynecology and obstetrics in times of COVID-19 : recommendations of the National Specialized Commission on Medical Residency of FEBRASGO

* Text prepared by the members of the National Specialized Commission on Medical Residency and endorsed by the Scientific Board and Presidency of the Brazilian Federation of Gynecology and Obstetrics Associations (FEBRASGO)

Resistance training with different repetition duration to failure: effect on hypertrophy, strength and muscle activation

Background This study investigated the effects of two 14-week resistance training protocols with different repetition duration (RD) performed to muscle failure (MF) on gains in strength and muscle hypertrophy as well as on normalized electromyographic (EMG) amplitude and force-angle relationships. Methods The left and right legs of ten untrained males were assigned to either one of the two protocols (2-s or 6-s RD) incorporating unilateral knee extension exercise. Both protocols were performed with 3–4 sets, 50–60% of the one-repetition maximum (1RM), and 3 min rest. Rectus femoris and vastus lateralis cross-sectional areas (CSA), maximal voluntary isometric contraction (MVIC) at 30o and 90o of knee flexion and 1RM performance were assessed before and after the training period. In addition, normalized EMG amplitude-angle and force-angle relationships were assessed in the 6th and 39th experimental sessions. Results The 6-s RD protocol induced larger gains in MVIC at 30o of knee angle measurement than the 2-s RD protocol. Increases in MVIC at 90o of knee angle, 1RM, rectus femoris and vastus lateralis CSA were not significant between the 2-s and 6-s RD protocols. Moreover, different normalized EMG amplitude-angle and force-angle values were detected between protocols over most of the angles analyzed. Conclusion Performing longer RD could be a more appropriate strategy to provide greater gains in isometric maximal muscle strength at shortened knee positions. However, similar maximum dynamic strength and muscle hypertrophy gains would be provided by protocols with different RD

Electromyographic analysis of stomatognathic muscles in elderly after hippotherapy.

The aging process affects the entire human body, including the stomatognathic system, and can trigger not only occlusal but also postural imbalances involving other muscular chains. Hippotherapy has been used to promote cervical, postural, and balance control in individuals with diverse impairments. The present study used electromyography to evaluate the masseter and temporal muscles in an elderly population pre- and post-hippotherapy. Participants included 17 individuals, mean age 66,5±7 years. Electromyographic recording of the bilateral masseter and temporal muscles was performed during the postural resting condition and activities that involved the active participation of these muscles in different conditions. The practitioner performed no other type of activity or exercise during the intervention because the objective is to evaluate the effect of the three-dimensional movement provided by the horse. Raw electromyographic data were tabulated using commercially available software (IBM® SPSS® Statistics 234.0) and subjected to statistical analysis, in which p ≤ 0.05 was considered to be statistically significant. Post-hippotherapy, there was lower electromyographic activity for the masseter and temporalis muscles in all the static mandibular tasks, with significant effect for time for the right temporal muscle (p = 0.038), the left temporal muscle (p = 0.028) and in the all dynamic mandibular tasks for the left temporal muscle (p = 0.025) and the left masseter muscle (p = 0.027). Hippotherapy promotes a reduction in the myoelectric activity of the masticatory muscles of elderly individuals

Reemergence of Dengue Virus Serotype 3, Brazil, 2023

We characterized 3 autochthonous dengue virus serotype 3 cases and 1 imported case from 2 states in the North and South Regions of Brazil, 15 years after Brazil's last outbreak involving this serotype. We also identified a new Asian lineage recently introduced into the Americas, raising concerns about future outbreaks

Reemergence of Dengue Virus serotype 3, Brazil, 2023

Fundação Oswaldo Cruz. Rio de Janeiro, RJ, Brazil / Fundação Oswaldo Cruz. Manaus, AM, Brazil.Centers for Disease Control and Prevention. San Juan, PR, USA.Laboratório Central de Saúde Pública de Roraima. Boa Vista, RR, Brazil.Laboratório Central de Saúde Pública de Roraima. Boa Vista, RR, Brazil.Fundação Oswaldo Cruz. Manaus, AM, Brazil.Fundação Oswaldo Cruz. Manaus, AM, Brazil.Fundação Oswaldo Cruz. Manaus, AM, Brazil.Fundação Oswaldo Cruz. Manaus, AM, Brazil.Fundação Oswaldo Cruz. Manaus, AM, Brazil.Fundação de Vigilância em Saúde Dra. Rosemary Costa Pinto. Manaus, AM, Brazil.Fundação de Medicina Tropical Dr Heitor Vieira Dourado. Manaus, AM, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Laboratório Central de Saúde Pública do Paraná. Curitiba, PR, Brazil.Laboratório Central de Saúde Pública do Paraná. Curitiba, PR, Brazil.Laboratório Central de Saúde Pública do Paraná. Curitiba, PR, Brazil.Fundação Oswaldo Cruz. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Rio de Janeiro, RJ, BrazilFundação Oswaldo Cruz. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Recife, PE, Brazil.Fundação Oswaldo Cruz. Recife, PE, Brazil.Fundação Oswaldo Cruz. Curitiba, PR, Brazil.Universidade Federal do Espírito Santo. Alegre, ES, Brazil.Florida Department of Health. Tampa, FL, USA.Florida Department of Health. Tampa, FL, USA.Centers for Disease Control and Prevention. San Juan, PR, USA.Fundação Oswaldo Cruz. Rio de Janeiro, RJ, Brazil.We characterized 3 autochthonous dengue virus serotype 3 cases and 1 imported case from 2 states in the North and South Regions of Brazil, 15 years after Brazil’s last outbreak involving this serotype. We also identified a new Asian lineage recently introduced into the Americas, raising concerns about future outbreaks