Beta-alanine supplementation (BA) has a positive impact on physical performance. However, evidence showing a benefit of this amino acid in aerobic–anaerobic transition zones is scarce and the results controversial. The aim of this systematic review and meta-analysis is to analyze the effects of BA supplementation on physical performance in aerobic–anaerobic transition zones. At the same time, the effect of different dosages and durations of BA supplementation were identified. The search was designed in accordance with the PRISMA® guidelines for systematic reviews and meta-analyses and performed in Web of Science (WOS), Scopus, SPORTDiscus, PubMed, and MEDLINE between 2010 and 2020. The methodological quality and risk of bias were evaluated with the Cochrane Collaboration tool. The main variables were the Time Trial Test (TTT) and Time to Exhaustion (TTE) tests, the latter separated into the Limited Time Test (LTT) and Limited Distance Test (LDT). The analysis was carried out with a pooled standardized mean difference (SMD) through Hedges’ g test (95% CI). Nineteen studies were included in the systematic review and meta-analysis, revealing a small effect for time in the TTT (SMD, −0.36; 95% CI, −0.87–0.16; I2 = 59%; p = 0.010), a small effect for LTT (SMD, 0.25; 95% CI, −0.01–0.51; I2 = 0%; p = 0.53), and a large effect for LDT (SMD, 4.27; 95% CI, −0.25–8.79; I2 = 94%; p = 0.00001). BA supplementation showed small effects on physical performance in aerobic–anaerobic transition zones. Evidence on acute supplementation is scarce (one study); therefore, exploration of acute supplementation with different dosages and formats on physical performance in aerobic–anaerobic transition zones is needed.
(Rev Med Chile 2017; 145: 972-979)
Diversas investigaciones han determinado que la implementación de programas de actividad física mejora la salud mental. Sin embargo, aún existen dudas sobre los beneficios de los programas Zumba® en la población que lo practica. El propósito de este estudio fue determinar los efectos de un programa de ejercicio físico basado en Zumba®, sobre los niveles de ansiedad-rasgo y ansiedad-estado en estudiantes universitarias chilenas. Investigación cuantitativa cuasi-experimental, con una muestra de 22 estudiantes mujeres de pregrado (grupo experimental = 10 y grupo control = 12). Las variables fueron: ansiedad-rasgo (A-R) y ansiedad-estado (A-E), además de variables físicas como antropometría, consumo máximo de oxígeno (VO2máx) y fuerza prensil. El análisis estadístico se realizó a través de un ANOVA mixto para todas las variables. En nivel de significancia fue de p < 0,05. Los resultados evidenciaron cambios no significativos en los distintos niveles de A-R ni A-E luego de la aplicación del programa de Zumba® (p > 0,05), tampoco hubo cambios en las otras variables de estudio (p > 0,05). Al término de la intervención, no se observaron efectos del programa de Zumba® sobre los distintos niveles de A-R y A-E, como tampoco sobre variables antropométricas, VO2máx ni fuerza prensil. Several investigations have specified that the implementation of physical activity programs improve mental health. However, there are still doubts about the benefits on the population taking part in Zumba® programs. The purpose of this study was to determine the effects of a Zumba® based working out program on the levels of anxiety-trait and anxiety-state in Chilean university students. It was a quantitative, cuasi-experimental study with a sample of 22 undergraduate female students (experimental group = 10 and control group = 12). The variables were anxiety-trait (A-T) and anxiety-state (A-S), in addition to physical variables, such as anthropometry, maximum oxygen consumption (VO2max) and grip strength. A statistical analysis was performed through a mixed ANOVA. The level of significance for all analyses was p < 0.05. The results showed no significant changes in the different levels of A-T or A-S (p > 0.05), there were also no changes in the other variables (p > 0.05). At the end of the intervention, no effects of the Zumba® program were observed on the different levels of A-T and A-S, nor on anthropometric variables, VO2max or grip strength. Várias investigações determinaram que a implementação de programas de atividade física melhora a saúde mental. No entanto, ainda existem dúvidas sobre os benefícios dos programas Zumba® na população que pratica. O objetivo deste estudo foi determinar os efeitos de um programa de exercícios físicos baseado no Zumba®, sobre níveis de Ansiedade-Traço e Ansiedade-Estado em estudantes universitários chilenos. Pesquisa quantitativa quase experimental, com uma amostra de 22 estudantes do sexo feminino (grupo experimental [GE] = 10 e grupo controle [GC] = 12). As variáveis foram: Ansiedade-Traço (A-T) e Ansiedade-Estado (A-E), ambas avaliadas pelo STAI Trait State Anxiety Questionnaire, além de variáveis físicas como antropometria, consumo máximo de oxigênio (VO2máx) e força pré-trilateral. A análise estatística foi realizada através de uma ANOVA mista para todas as variáveis e uma tabela de contingência por meio do Qui-Quadrado de Pearson para os diferentes níveis de A-T e A-E. O nível de significância para todas as análises foi de p <0,05. Os resultados não mostraram alterações significativas em todas as variáveis do estudo após a aplicação do programa Zumba® (p> 0,05); também não houve diferenças nos diferentes níveis de A-T ou A-E (p> 0,05). Ao final da intervenção, não foram observados efeitos do programa Zumba® sobre diferentes níveis de A-R e A-E, nem nas variáveis antropométricas, VO2máx ou força preênsil.
Physical exercise has a positive impact on anxiety and depression. However, the evidence that associates strength training with a decrease in adolescents’ psychosocial disorders is scarce. Consequently, the objective was to analyze the effects of training with different modes of strength intervention on anxiety, stress, and depression in adolescents. The search was designed according to PRISMA®. We searched WoS, Scopus, SPORTDiscus, PubMed, and MEDLINE (2010–2020). Methodological quality and risk of bias were assessed with the Cochrane Collaboration. The analysis was carried out with a standardized mean difference (SMD) pooled using the Hedges g test (95% CI). The Main Outcome Measures were: anxiety, stress, and depression in adolescents post strength training. Nine studies were included in the systematic review and seven in the meta-analysis. These studies showed a large and significant effect of strength training on anxiety (SMD = −1.75; CI = 95%: −3.03, −0.48; p = 0.007) and depression (SMD = −1.61; CI = 95%: −2.54, −0.67, p = 0.0007). In conclusion, training with different modes of strength intervention have shown control over anxiety and depression in adolescents. However, conventional strength training seems to have better results than other modes of strength intervention.
Introduction: The development of strength has shown to be beneficial to sports performance and health. However, during strength training, they also produce alterations in muscle fatigue indicators, leading to a decrease in the ability to generate strength. Despite this, there is still not enough knowledge about the levels of muscle fatigue generated by different methods of strength training and how this information can be integrated into sports planning. Review and analyze the studies existing between January 2009 and January 2019 that have used indicators of muscle fatigue established in the search terms during and after strength training as measurement variables. Evidence acquisition: The study corresponds to a systematic review of previously published studies, following the PRISMA model. Articles published between 2009 and 2019 that measured muscle fatigue indicators during and after strength training were evaluated. The electronic search was conducted through Web of Science, Scopus, Sport Discus, PubMed, and Medline. We included all articles that used a strength protocol and also measured indicators of muscle fatigue and its possible effect on physical performance. Evidence synthesis: A total of 39 articles were found, which were stratified according to the protocol used: (i) plyometric training, (ii) Bodypump® training, (iii) occlusion training, (iv) variable resistance training, (v) conventional strength training, (vi) eccentric strength training, (vii) rest times in strength training and (viii) concurrent training. Conclusion: At the end of the systematic review, it was shown that the different training methodologies for strength development generate increases in muscle fatigue indicators, and the increase generated in the different muscle fatigue indicators depends both on the methodology used and on the type of population, sex, level of training and type of sport. The most-reported indicators are [La], HR and RPE, DOM, MR variation, and ammonium.
Introducción: Un entrenamiento pliométrico basado en HIIT que mejore la potencia muscular en futbolistas adolescentes, aún no ha sido del todo estudiado. Objetivo: Analizar el efecto de un entrenamiento pliométrico basado en HIIT sobre la potencia muscular en futbolistas Sub-17. Materiales y métodos: Veinticuatro futbolistas divididos en dos grupos fueron parte del estudio (Grupo Experimental [GE] n = 12 y Grupo Control n = 12). Las variables fueron: altura (h) de salto y Pico de potencia (Pp) a través del Test de Sargent. El protocolo utilizado fue un entrenamiento pliométrico basado en HIIT. Para el análisis estadístico se utilizó la prueba t de Student y el tamaño del efecto fue calculado con la prueba d de Cohen. Resultados: La h en el Test de Sargent presentó un aumento significativo post intervención sólo para el GE (p < 0.0001; Tamaño del Efecto = 0.763). En relación a los Pp, sólo el GE presentó un aumento significativo post intervención (p < 0.0001; Tamaño del Efecto = 0.413). Conclusiones: Los resultados dejaron en evidencia que el entrenamiento pliométrico basado en HIIT es una herramienta efectiva para incrementar la h de salto y Pp en futbolistas adolescentes Sub-17.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.