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Este estudo teve como objetivo compreender os principais efeitos causados de forma aguda pelo exercício com restrição de fluxo sanguíneo no desempenho físico. Trata-se de um estudo de revisão de escopo, com base nas recomendações indicadas no PRISMA-ScR. Utilizou-se as seguintes bases de dados: Web of Science (Categorias: Ciências do esporte e fisiologia), PubMed, SPORTDicus. As estratégias de busca nas bases de dados escolhidas permitiram encontrar um total de 3028 manuscritos. Após a triagem e seleção de fontes de evidência foram incluídos um total de 22 artigos na revisão de escopo. Os achados desta revisão de escopo nos permitem afirmar que a restrição de fluxo sanguíneo, aplicada de forma aguda no exercício resistido, é eficaz no aumento da potência de pico, combinada com altas ou baixas cargas e de curto prazo, bem como seu uso com altas ou baixas pressões de restrição é uma ferramenta viável para melhora do desempenho de força e resistência de força, assim como aumentos na hipertrofia muscular. É possível concluir também que a restrição de fluxo sanguíneo aplicada de forma aguda no exercício aeróbico, não gera efeitos positivos no desempenho físico em marcadores como: volume de oxigênio (VO2), consumo excessivo de oxigênio pós exercício (EPOC), frequência cardíaca e acúmulo de lactato, quando comparado ao mesmo protocolo sem restrição de fluxo.

Introduction: Physical training with blood flow restriction (BFR) may provide health benefits for people with diabetes. However, the negative effects cannot be overlooked. Aim: This study aimed to analyze the acute effect of resistance exercise BFR on the rating of perceived exertion (RPE) and subjective perception of pain in untrained women with type 2 diabetes (T2DM). Methods: Ten untrained women with T2DM (56.9 ± 7.4 years; diagnostic time: 10.6 ± 4.1 years) participated in this study. Participants attended a local gym for four non-consecutive days. Initially, predictive values of one maximum repetition (1RM) and arterial occlusion pressure (AOP) were measured. In random order, second, third, and fourth visits were allocated to the following: high-load (HL) exercise (65% 1RM; three sets of 10 repetitions), low-load (LL) exercise (20% of 1RM; three sets of 15 repetitions), and LL exercise with BFR (LL+BFR) (20% 1RM; three sets of 15 repetitions; 50% of AOP). RPE and pain perception were assessed immediately after each set. RPE increased significantly over the sets for all exercise protocols (p

Introdução: Sabe-se que em diversos casos a Idade Cronológica não condiz com a Idade Biológica (IB), e que no processo de Seleção de Talentos Esportivos quanto mais avançada a IB, mais vantagens em relação ao desempenho neuromuscular dos atletas devido ao aprimoramento do sistema musculoesquelético. Objetivo: Este estudo teve como objetivo analisar a correlação entre a IB e a potência muscular de membros inferiores em atletas de futebol. Materiais e Métodos: Estudo transversal com amostra de dezesseis atletas do sexo masculino (idade: 13,35±0,90) onde foram submetidos a uma avaliação antropométrica e um teste de salto vertical contramovimento. Os dados antropométricos foram utilizados para estimar a idade esquelética, enquanto o teste de salto vertical foi utilizado para avaliar a potência de MMII. Resultados: O estudo apontou Correlação Positiva entre a IB e a Potência de Membros Inferiores (r:0,675; CI 95%:0,269; 0,877; p=0,004) identificando que o avanço da IB contribuiu em 45% (contribuição média) para a Potência dos Membros Inferiores (r2: 0,455; F(1.0):11,7; β: 1,83; CI 95% β: 0,68; 2,98; p=0,004). Discussão: Os resultados sugerem que quanto mais avançada a maturação biológica, maior será a potência muscular de membros inferiores em jovens atletas de futebol, contribuindo em 45% para sua performance. Conclusão: Sendo assim, o avançar da Idade Biológica está positivamente relacionado com o desempenho da potência de membros inferiores em atletas de futebol do sexo masculino. Desta forma, sugere-se que atletas com IB avançada possuem maior nível de potência muscular em relação aos seus pares em estágios de IB atrasado ou sincronizado.

Abstract Background Relative age effect (RAE) is a concept related to the possible advantage that older athletes would have over younger ones within the same category. Although many studies have approached this subject in individual sports, there are few clippings by events within the sport. More detailed analyses are necessary for a better understanding of how RAE behaves in sports, especially in athletics, the subject of this study. The objective of this study was to analyze the RAE on speed in track and field events as a whole, separating the flat races from the hurdles races. Methods The Brazilian Ranking of Brazilian Athletics Confederation was used for data analysis, and the sample was composed of the 50 best-placed marks in the ranking of speed events in athletics in the categories Under(U)-16 and U-18 (female and male). Statistical analysis was calculated by chi-square, and the effect size was checked by Cramer’s V. Likelihood-ratio test (L-Ratio) assessed the probability of the RAE occurring in the total sample and by age groups. Results In the total sample the results pointed to the emergence of RAE in males in both categories (U-16: p

Purpose There is no consensus in literature data about the influence of biological maturation (BM) on swim performance in young athletes. We analysed the relationship of BM, upper-limb power (ULP), and lower-limb power (LLP) with adolescent athletes’ performance in crawl swim. Methods This observational study determined the BM of 16 competitive swimmers (50% males and 50% females; 12.90 ± 0.88 years) by a mathematical model based on bone age and anthropometric measures. ULP and LLP were established by the horizontal launch test and the vertical and countermovement jump tests on a force platform, respectively. Swim performance was evaluated by the average speed in a 100-m crawl sprint. Results BM was related to ULP (males: r = 0.76, p = 0.001; females: r = 0.39, p = 0.02), LLP (males: vertical jump r = 0.80, p = 0.02, countermovement jump r = 0.48, p = 0.02; females: vertical jump r = 0.30, p = 0.04, countermovement jump r = 0.80, p = 0.01), and crawl swim performance (males: r = –0.91, p = 0.001; females: r = –0.72, p = 0.04). BM had a 87% contribution to crawl swim performance in males and a 66% contribution in females. ULP and LLP showed < 50% contribution to crawl swim performance in both females and males. Conclusions BM was associated with crawl swim performance of adolescent athletes of both sexes. BM exhibited a stronger contribution to crawl swim performance than ULP and LLP in adolescent swimmers at the puberty window.

Social distancing towards prevention of the outspread of COVID-19 pandemics in the year of 2020 may significantly contribute towards physical inactivity of citizens worldwide. The objective of the current study was to quantify the impact of such preventive measure over the physical activity level of young Brazilian athletes across several sporting areas. Sixty-eight (68) Brazilian athletes (14.7 ± 1.68 years) answered to adapted version of the International Physical Activity Questionnaire (I-PAQ) through an online platform. It was requested that participants reported on their level of physical activity before and during the social distancing period. 67.7% of interviewed athletes stated being able to adapt their sports training to their isolation environment under a physical education professional`s distance guidance. Only 4.38% of the sample were not training under such a supervision and therefore inactive. Therefore, despite social distancing, the sampled athletes seem to remain physically active.

BackgroundHigh frequency (1-2 times per day) low-intensity blood flow restriction (BFR) training has been recommended as a prescription approach for short durations of time to maximize relevant physiological adaptations. However, some studies demonstrate negative physiological changes after short periods of high-frequency BFR training, including prolonged strength decline and muscle fiber atrophy.ObjectivesTo provide a comprehensive overview of short-term, high-frequency blood flow restriction training, including main adaptations, myocellular stress, limitations in the literature, and future perspectives.MethodsA systematic search of electronic databases (Scopus, PubMed®, and Web of Science) was performed from the earliest record to April 23, 2022. Two independent reviewers selected experimental studies that analyzed physical training protocols (aerobic or resistance) of high weekly frequency (>4 days/week) and short durations (≤3 weeks).ResultsIn total, 22 studies were included in this review. The samples were composed exclusively of young predominantly male individuals. Muscle strength and hypertrophy were the main outcomes analyzed in the studies. In general, studies have demonstrated increases in strength and muscle size after short term (1-3 weeks), high-frequency low-intensity BFR training, non-failure, but not after control conditions (non-BFR; equalized training volume). Under failure conditions, some studies have demonstrated strength decline and muscle fiber atrophy after BFR conditions, accompanying increases in muscle damage markers. Significant limitations exist in the current HF-BFR literature due to large heterogeneities in methodologies.ConclusionThe synthesis presented indicates that short-term, high-frequency BFR training programs can generate significant neuromuscular adaptations. However, in resistance training to failure, strength declines and muscle fiber atrophy were reported. Currently, there are no studies analyzing low-frequency vs. high-frequency in short-term BFR training. Comparisons between resistance exercises of similar intensities (e.g., combined effort) are lacking, limiting conclusions on whether the effect is a product of proximity to failure or a specific effect of BFR.

Background: Low-load resistance exercise (LL-RE) with blood flow restriction (BFR) promotes increased metabolic response and fatigue, as well as more pronounced myoelectric activity than traditional LL-RE. Some studies have shown that the relative pressure applied during exercise may have an effect on these variables, but existing evidence is contradictory.Purpose: The aim of this study was to systematically review and pool the available evidence on the differences in neuromuscular and metabolic responses at LL-RE with different pressure of BFR.Methods: The systematic review and meta-analysis was reported according to PRISMA items. Searches were performed in the following databases: CINAHL, PubMed, Scopus, SPORTDiscus and Web of Science, until June 15, 2021. Randomized or non-randomized experimental studies that analyzed LL-RE, associated with at least two relative BFR pressures [arterial occlusion pressure (AOP)%], on myoelectric activity, fatigue, or metabolic responses were included. Random-effects meta-analyses were performed for MVC torque (fatigue measure) and myoelectric activity. The quality of evidence was assessed using the PEDro scale.Results: Ten studies were included, all of moderate to high methodological quality. For MVC torque, there were no differences in the comparisons between exercise with 40–50% vs. 80–90% AOP. When analyzing the meta-analysis data, the results indicated differences in comparisons in exercise with 15–20% 1 repetition maximum (1RM), with higher restriction pressure evoking greater MVC torque decline (4 interventions, 73 participants; MD = −5.05 Nm [95%CI = −8.09; −2.01], p = 0.001, I2 = 0%). For myoelectric activity, meta-analyses indicated a difference between exercise with 40% vs. 60% AOP (3 interventions, 38 participants; SMD = 0.47 [95%CI = 0.02; 0.93], p = 0.04, I2 = 0%), with higher pressure of restriction causing greater myoelectric activity. This result was not identified in the comparisons between 40% vs. 80% AOP. In analysis of studies that adopted pre-defined repetition schemes, differences were found (4 interventions, 52 participants; SMD = 0.58 [95%CI = 0.11; 1.05], p = 0.02, I2 = 27%).Conclusion: The BFR pressure applied during the LL-RE may affect the magnitude of muscle fatigue and excitability when loads between 15 and 20% of 1RM and predefined repetition protocols (not failure) are prescribed, respectively.Systematic Review Registration: [http://www.crd.york.ac.uk/prospero], identifier [CRD42021229345].

BackgroundThe purpose of this review was to systematically analyze the evidence regarding the occurrence of muscle damage (changes in muscle damage markers) after resistance training with blood flow restriction sessions.Materials and methodsThis systematic review was conducted in accordance with the PRISMA recommendations. Two researchers independently and blindly searched the following electronic databases: PubMed, Scopus, Web of Science, CINAHL, LILACS and SPORTdicus. Randomized and non-randomized clinical trials which analyzed the effect of resistance training with blood flow restriction on muscle damage markers in humans were included. The risk of bias assessment was performed by two blinded and independent researchers using the RoB2 tool.ResultsA total of 21 studies involving 352 healthy participants (men, n = 301; women, n = 51) were eligible for this review. The samples in 66.6% of the studies (n = 14) were composed of untrained individuals. All included studies analyzed muscle damage using indirect markers. Most studies had more than one muscle damage marker and Delayed Onset Muscle Soreness was the measure most frequently used. The results for the occurrence of significant changes in muscle damage markers after low-load resistance training with blood flow restriction sessions were contrasting, and the use of a pre-defined repetition scheme versus muscle failure seems to be the determining point for this divergence, mainly in untrained individuals.ConclusionsIn summary, the use of sets until failure is seen to be determinant for the occurrence of significant changes in muscle damage markers after low-load resistance training with blood flow restriction sessions, especially in individuals not used to resistance exercise.Trial registrationRegister number: PROSPERO number: CRD42020177119.

Maturation interferes with physiological and mechanical aspects of muscle contraction. The aim of the present study was to compare the efficiency of the stretch-shortening cycle (SSC) between different maturation stages. One hundred forty six young people, with 72 boys and 74 girls, were recruited to participate in the study. Sexual maturation was measured and the group was stratified into adolescents (> 3 auto-tanner) and children (