Does the sequence of plyometric and dynamic stretching exercises influence subsequent sprint performance? A randomized crossover intervention study.

The objectives of this study were to evaluate the acute effects of the sequence order of drop jumps (DJ) and dynamic stretching (DS) on sprinting performances in competitive athletes and to investigate the relationships between post-activation performance enhancement (PAPE) in sprint performance and lower limb power. Thirteen male jumpers and sprinters participated in this study (19 ± 2 years; 177 ± 7 cm; 71.7 ± 5.6 kg). Through a randomized crossover design, the athletes were exposed to three different conditions after a standardized warm-up: DS+DJ, DJ+DS, and control. Sprinting performance over 40 m was analysed with consideration of initial (0 to 20 m) and final acceleration (20 to 40 m) phases. The effect of intervention was examined by two-way repeated-measures of ANOVA. Pearson's correlation test was used to determine the association between PAPE during sprinting and jump performance. There was no effect of any factor on 40-m sprint performance. Meanwhile, the performance at 20-40 m was higher after the DS+DJ condition when compared to baseline (8.79 ± 0.43 vs. 8.91 ± 0.35 m/s; p = 0.015). However, the initial acceleration was worsened in the DJ+DS condition when compared to baseline (6.26 ± 0.25 vs. 6.22 ± 0.26 m/s; p = 0.002). There was a negative correlation between CMJ height and the improvement in final acceleration (r = -0.741; p = 0.004). The use of DS prior to DJ is an effective strategy to improve performance in the final acceleration phase (20-40 m). The athletes with lower levels of lower limb power benefited the most from this PAPE strategy.

Post-activation performance enhancement effect of drop jump on long jump performance during competition.

Drop jump is widely used in training sessions, aiming for chronic effects on long jump performance. However, the acute effect of drop jump on long jump performance through its use as a Conditioning Activity (CA) has not been explored. The objective of this study was to verify the Post-activation Performance Enhancement (PAPE) responses induced by successive Drop Jumps (DJ) on competitive long jump performance. Eleven male jumpers (19.0 ± 2.0 years; 178.0 ± 9.0 cm; 73.1 ± 8.9 kg; and personal record 5.78 ± 0.44 m) volunteered for participation. The athletes performed 5 drop jumps 2 min (1'45-2'15 min) before the second, and fourth attempt during official competition of state level, the attempts without the use of CA were considered controls. The performance of the second (5.63 ± 0.43 m), third (5.65 ± 0.46, g = 0.24) and fourth (5.71 ± 0.34 m) jumps performed after activation were higher than the first (5.54 ± 0.45 m) in the control condition, p = 0.02, and p = 0.01 respectively. Differences were also found in the take-off vertical velocity of the jump between the fourth (1.55 ± 0.21) and the first jump (1.30 ± 0.40), p = 0.006. Jump performance showed positive correlation with approach velocity, r = 0.731, vertical take-off velocity, r = 0.412, and take-off duration, r = 0.508. The mean performance in jumping post-activation (5.67 ± 0.38 m) was higher than that without the use of previous CA (5.59 ± 0.44 m), p = 0.02, g = 0.19. The use of DJs as a CA prior to the long jump promotes improvements in the performance of the jump, which can be explained by the increase in the take-off vertical velocity in the athletes.

Acute effects of transcranial direct current stimulation (tDCS) on peak torque and 5000 m running performance: a randomized controlled trial.

The benefits of transcranial direct current stimulation (tDCS) on brain function, cognitive response, and motor ability are well described in scientific literature. Nevertheless, the effects of tDCS on athletes' performance remain unclear. To compare the acute effects of tDCS on the running performance of 5000 m (m) runners. Eighteen athletes were randomized into Anodal (n = 9) groups that received tDCS for 20 min and 2 mA, and Sham (n = 9), in the motor cortex region (M1). Running time in 5000 m, speed, perceived exertion (RPE), internal load and peak torque (Pt) were evaluated. The Shapiro-Wilk test followed by a paired Student's t-test was used to compare Pt and total time to complete the run between the groups. The running time and speed of the Anodal group (p = 0.02; 95% CI 0.11-2.32; d = 1.24) was lower than the Sham group (p = 0.02, 95% CI 0.05-2.20; d = 1.15). However, no difference was found in Pt (p = 0.70; 95% CI - 0.75 to 1.11; d = 0.18), RPE (p = 0.23; 95% CI - 1.55 to 0.39; d = 0.60) and internal charge (p = 0.73; 95% CI - 0.77 to 1.09; d = 0.17). Our data indicate that tDCS can acutely optimize the time and speed of 5000 m runners. However, no alterations were found for Pt and RPE.

Effects of High-Intensity Warm-Up on 5000-Meter Performance Time in Trained Long-Distance Runners.

Warm-up protocols with high intensities before continuous running provide potential benefits for middle-distance runners. Nevertheless, the effect of high-intensity warm-ups on long-distance runners remains unclear. The purpose of this study was to verify the effect of a high-intensity warm-up protocol on 5000 m performance in trained runners. Thirteen male runners (34 ± 10 years, 62 ± 6 kg, 62.7 ± 5.5 ml/kg/min) performed two 5000 m time trials, preceded by two different warm-ups. One high-intensity warm up (HIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (100% of the running intensity) and one low-intensity warm up (LIWU: 1x 500 m (70% of the running intensity) + 3x 250 m (70% of the running intensity)), where the running intensities were calculated using the results obtained in the Cooper test. Physiological and metabolic responses, and endurance running performance parameters, were evaluated by the Counter Movement Jump (CMJ), running rating of perceived exertion (RPE), blood lactate concentration (BLa), and performance running. Total time for the 5000 m was lower using HIWU when compared to LIWU (1141.4 ± 110.4 s vs. 1147.8 ± 111.0 s; p = 0.03; Hedges' g = 0.66). The HIWU warm-up led to an improvement in pacing strategy during the time trial. After warm-up protocols, the performance on the CMJ was improved only when applying HIWU (p = 0.008). Post warm-up BLa was significantly higher for HIWU vs. LIWU (3.5 ± 1.0 mmol·L-1 vs. 2.3 ± 1.0 mmol·L-1; p = 0.02), with similar behavior for the RPE (p = 0.002), internal load of the session (p = 0.03). The study showed that a high-intensity warm-up protocol can improve performance in the 5000 m in trained endurance runners.

Completeness and quality of information about death from COVID-19 in a Brazilian state: A descriptive population-based register study.

Health information is particularly essential in times of pandemics in which rapid response is crucial for political and stakeholder decision-making processes, and therefore the availability of data as well as its quality analysis are necessary. This study aimed to describe the completeness and quality of the e-Sistema Único de Saúde (SUS) Health Surveillance database (SUS Vigilância em Saúde) of the state of Espírito Santo, Brazil, from the notification of deaths from corana virus disease 2019 (COVID-19) from January 2020 to June 2021. A descriptive population-based register study was conducted from the analysis of the completeness of secondary data from the record of deaths from COVID-19, retrieved from the e-SUS Vigilância em Saúde (Health Surveillance) (VS) database of the state of Espírito Santo, Brazil, from January 2020 to June 2021. A total of 11,359 death records from COVID-19 via e-SUS VS in the state of Espírito Santo, Brazil, were evaluated. The score used to assess incompleteness was the 1 proposed by Romero and Cunha which classifies as excellent (when < 5%), good (between 5% and 10%), regular (between 10% and 20%), poor (between 20% and 50%), and very poor (when > 50%), according to the percentage of the absence of information. Descriptive statistical analyses were conducted in the Stata program, version 15.1. "Case identification" variables, and "condition" variables were classified as excellent completeness. Among the evolution variables, only "hospitalization" was classified as regular. Among the laboratory variables, only the polymerase chain reaction presented excellent completeness, while the "rapid test" and "serologies for immunoglobulin G, and immunoglobulin M" variables were classified as good completeness. It is concluded that most of the variables available in e-SUS VS of the state of Espírito Santo, Brazil, of notification of deaths from COVID-19 in 2020 presented excellent completeness, confirming the excellent quality of the state database.

Acute Neuromuscular, Physiological and Performance Responses After Strength Training in Runners: A Systematic Review and Meta-Analysis.

BACKGROUND: Strength training (ST) is commonly used to improve muscle strength, power, and neuromuscular adaptations and is recommended combined with runner training. It is possible that the acute effects of the strength training session lead to deleterious effects in the subsequent running. The aim of this systematic review and meta-analysis was to verify the acute effects of ST session on the neuromuscular, physiological and performance variables of runners. METHODS: Studies evaluating running performance after resistance exercise in runners in the PubMed and Scopus databases were selected. From 6532 initial references, 19 were selected for qualitative analysis and 13 for meta-analysis. The variables of peak torque (PT), creatine kinase (CK), delayed-onset muscle soreness (DOMS), rating of perceived exertion (RPE), countermovement jump (CMJ), ventilation (VE), oxygen consumption (VO2), lactate (La) and heart rate (HR) were evaluated. RESULTS: The methodological quality of the included studies was considered reasonable; the meta-analysis indicated that the variables PT (p = 0.003), DOMS (p < 0.0001), CK (p < 0.0001), RPE (p < 0.0001) had a deleterious effect for the experimental group; for CMJ, VE, VO2, La, FC there was no difference. By qualitative synthesis, running performance showed a reduction in speed for the experimental group in two studies and in all that assessed time to exhaustion. CONCLUSION: The evidence indicated that acute strength training was associated with a decrease in PT, increases in DOMS, CK, RPE and had a low impact on the acute responses of CMJ, VE, VO2, La, HR and submaximal running sessions.

Changes in Cytokines Concentration Following Long-Distance Running: A Systematic Review and Meta-Analysis.

Long-distance running is an exhausting effort for the whole organism. Prolonged aerobic exercise induces changes in inflammatory markers. However, predicting muscle damage in response has limitations in terms of selecting biomarkers used to measure inflammatory status. The present study conducts a systematic review and meta-analysis of articles focusing in ultra-marathon, marathon, and half-marathon and levels of cytokines. The search was conducted in PubMed, Web of Science, and Scopus databases, resulting in the inclusion of 76 articles. IL-6 was highlighted, evaluated in 62 studies and show increase in the standard mean difference (SMD): half-marathon (SMD -1.36; IC 95%: -1.82, -0.89, Ch2:0.58; tau2:0.00; p < 0.0001), marathon (SMD -6.81; IC 95%: -9.26, -4.37; Ch2:481.37 tau2:11.88; p < 0.0001) and ultra-marathon (SMD -8.00 IC 95%: -10.47, -5.53; Ch2:328.40; tau2:14.19; p < 0.0001). In contrast meta-regression analysis did not show relationship to the running distance (p = 0.864). The meta-analysis evidenced increase in the concentration of IL-1ra (p < 0.0001), IL-1B (p < 0.0001), IL-8 (p < 0.0001), IL-10 (p < 0.0001) and TNF-α (p < 0.0001). Reduction in IL-2 (p < 0.0001) and INF-y (p < 0.03) and no change in the IL-4 (p < 0.56). The number of studies evaluating the effect of adipokines was limited, however Leptin and Resistin were recurrent. The effects of an acute bout of prolonged aerobic exercise will protect against chronic systemic inflammation. The time to return to baseline values showed a substantial and dose-dependent relationship with run volume. The concentration of IL-6 was robustly studied and the marathon running was the most explored. Network of endocrine interactions in which circulating factors, released in extreme exercises, interplay through inter-organ crosstalk and physiologic changes were expressed. The running volume variability was able to modulate compounds that play a fundamental role in the maintenance of homeostasis and cell signaling.

Ultramarathon Evaluation above 180 km in relation to Peak Age and Performance.

Background: Ultramarathons with distances over 180 km might lead to different results regarding participation, performance, and age compared to shorter runs of 50 and 100 km. Objective: To evaluate ultramarathons with distances above 180 km in relation to runners' peak age and performance. Method: s. Verification of the quantity of competitions in runs over 180 km by continents in the period 2000 to 2020 and evaluation of the individual results of 13,300 athletes after 2010. Results: Europe stood out with the largest number of organized events, followed by Asia and North America. The age peak performance (PP) in men and women averaged 45 years old with relationship between sex × years (F = 3.612, p < 0.001; η2 = 0.003). Men accounted for more than 80% of the runners and showed a reduction in PP from 2015 onwards (p < 0.001). Competitions between 180 and 240 km were the most frequent, particularly after 2016, surpassing the number of marathons over 360 km (p < 0.001). Men and women showed higher velocity in distances (p < 0.001) from 180 to 240 km when compared to 241 to 300 k m, 301 to 360 km, and >360 km courses. Conclusions: The decade between 2010 and 2020 showed an increase in the number of Ultramarathon running events. Europe had the highest number. Women had low participation. Performance progression fell, a fact associated with an increase in the number of participants and not specifically related to a decline in athletic performance over the years.

Interactions between contact lenses and lens care solutions: Influence in optical properties.

PURPOSE: Investigate changes in optical properties of contact lenses materials (transmittance and reflectance) and lens care solutions (absorption and fluorescence) resulting from its interaction. METHODS: From an experimental study, triplicate measurements of transmittance and reflectance of five contact lenses (Senofilcon A, Lotrafilcon B, Balafilcon A, Comfilcon A, and Omafilcon A), as well as UV-vis absorption and fluorescence of four lens care solutions (LCS) (ReNu MultiPlus, Biotrue, OPTI-FREE PureMoist, and AOSept Plus), were evaluated before and after 8 h, one day and one week in storage. The outcomes were provided by Shimadzu UV3101-PC UV-vis-NIR spectrophotometer equipped with an integrating sphere, between 200-700 nm, and SPEX-Fluorolog 2 FL3-22 spectrofluorometer. RESULTS: All variables exhibited statistically significant differences over time. Comfilcon A showed the lowest ultraviolet radiation (UVR) A & B attenuation. Balafilcon A and Lotrafilcon B displayed a slight suppression of UVR. Senofilcon A was effective in UVR protection and showed less effect on the fluorescence of lens care solutions. Overall, the reflectance decreased after storage (p < 0.05). AOSept Plus absorbance and fluorescence demonstrated lower interactions than multipurpose solutions (MPS), and Lotrafilcon B induced more remarkable changes in optical properties of LCS than the other materials. CONCLUSION: The findings suggest that optical variables of lens care solutions and contact lenses changed mutually after storage, probably associated with biochemical and biophysical interactions between components and the release of some polymer compounds. These findings can provide additional information about the interaction of CL materials and LCS in clinical behavior.

Physical activity level in overweight adolescents at school: a systematic review / Nível de atividade física em jovens escolarizados com excesso de peso: uma revisão sistemática

Abstract - The objective of this systematic review was to identify the association between overweight/obesity and level of physical activity in Brazilian children and adolescents in the school setting. For search strategy, the main reference databases (PubMed, LILACS, SciELO, SPORTDiscus, Web of Science, ERIC) were used. Baseline searches resulted in 3,265 potentially relevant titles (2,775 titles after removal of duplicate studies); 21 studies met all inclusion criteria and were included for analysis. Studies were carried out from 2007 to 2019; 47.6% of them were conducted in Southern Brazil, and only one study had nationwide approach. Prevalence from 5.4% to 21% was identified for overweight, 3.5% to 16.9% for obesity and 11.8% to 40.1% for overweight + obesity. According to results, 64.3% of overweight, 69.8% of obese and 37.7% of young overweight people were considered insufficiently active. The non-standardization of instruments to assess levels of physical activity and the lack of information regarding other Brazilian regions were classified as important limitations. The results reinforce the increase in the prevalence of overweight in Brazilian children and adolescents, and the high prevalence of physical inactivity among them. For every ten overweight children/adolescents, six are reported to be insufficiently active.

Resumo - O objetivo desta revisão sistemática foi identificar a associação entre excesso de peso, obesidade e nível de atividade física em crianças e adolescentes brasileiros, no ambiente escolar. A busca eletrônica foi realizada nas principais bases de dados de referência (PubMed, LILACS, SciELO, SPORTDiscus, Web of Science, ERIC). A pesquisas nas bases resultaram em 3265 títulos potencialmente relevantes (2775 títulos após análise duplicada); 21 estudos preencheram todos os critérios de inclusão e foram analisados. Os estudos foram realizados entre 2007 e 2019, 47,6% deles foram realizados no sul do Brasil, e apenas uma pesquisa foi realizada a nível nacional. Foi identificado prevalências de 5,4% a 21% para sobrepeso, 3,5% a 16,9% para obesidade e 11,8% a 40,1% para excesso de peso (obesidade + sobrepeso). De acordo com os resultados, 64,3% dos jovens com sobrepeso, 69,8% dos obesos e 37,7% daqueles com excesso de peso foram considerados insuficientemente ativos. A não padronização dos instrumentos para avaliar os níveis de atividade física e a pouca representatividade de outras regiões brasileiras foram classificadas como lacunas importantes. Os resultados reforçam o aumento da prevalência de excesso de peso em crianças e adolescentes no Brasil, e a alta prevalência de inatividade física entre estes jovens. A cada dez jovens acima do peso, seis são insuficientemente ativos.

Structure for the practice of physical activities in Brazilian schools, Human Development Index and Basic Education Development Index: contributions to the Report Card Brazil / Estrutura para a prática de atividades físicas nas escolas brasileiras, Índice de Desenvolvimento Humano e Índice de Desenvolvimento da Educação Básica: contribuições para o Report Card Brasil

ABSTRACT The purpose of this study was to identify structures for the practice of physical activities (PA) in Brazilian Schools and relate them to the Human Development Index (HDI), Basic Education Development Index (IDEB) and quality indicators from the Report Card Brazil (RCB). This is a descriptive study that used secondary data from INEP-Brazil to identify and classify structures for the practice of PA in Brazilian schools based on the presence of "schoolyards", "sports courts" and "sporting materials", organized by elementary and high schools. Data were organized by Macroeconomic Region and related to HDI, IDEB and Report Card Brazil Quality Classification Criteria. Thus, for "Elementary School", positive and significant relationship was observed between HDI and the presence of "schoolyards" (r=0.53; p=0.004), "sports courts" (r=0.855; p<0, 01) and "sporting materials"(r=0.764; p<0.01), while for IDEB, values ​​followed the same logic, associated to the presence of "schoolyards" (r=0.475; p=0.01), "sports courts" (r=0.676; p<0.01) and "sporting materials" (r=0.535; p<0.01). For "High School", relationship was observed between HDI and the presence of "sports courts" (r=0.517; p<0.01) and "sporting materials" (r=0.499; p<0.01), while for IDEB, relationship was only observed with the presence of "sporting materials" (r=0.508; p<0.01). It could be concluded that the Northern and Northeastern regions of Brazil have schools with lower presence of structure for the practice of Physical Activity and that there is positive relationship of this structure with HDI, IDEB and quality indicators of the Report Card Brazil.

RESUMO O objetivo do estudo foi identificar as estruturas para atividades físicas (AF) nas escolas brasileiras e relacioná-las ao Índice de Desenvolvimento Humano (IDH), Índice de Desenvolvimento da Educação Básica (IDEB) e indicadores de qualidade do Report Card Brasil (RCB). Trata-se de estudo descritivo que utilizou dados secundários do INEP-Brasil para a identificação e classificação da estrutura para prática de AF nas escolas brasileiras, a partir da existência de "pátio", "quadras" e "materiais esportivos", organizadas por escolas do nível "fundamental" e "médio". Os dados foram organizados por Região Macroeconômica e relacionados com os Índices IDH, IDEB e os Critérios de Classificação de Qualidade do RCB. Assim, para o "Ensino Fundamental", verificou-se relação positiva entre o IDH e a existência de "pátio" (r=0,53; p=0,004), "quadra" (r=0,855; p<0,01) e material esportivo (r=0,764; p<0,01), o IDEB também apresentou relação positiva com a existência de "pátio" (r=0,475; p=0,01), "quadra esportiva" (r=0,676; p<0,01) e "material esportivo" (r=0,535; p<0,01). Para o "Ensino Médio", verificou-se relação entre o IDH e a existência de quadras (r=0,517; p<0,01) e materiais esportivos (r=0,499; p < 0,01), enquanto para o IDEB, apenas houve relação com a existência de materiais esportivos (r=0,508; p<0,01). Conclui-se que as Regiões Norte e Nordeste possuem escolas com menores frequências de estrutura para Atividade Física e que há relação positiva desta estrutura com o IDH, IDEB e classificação de qualidade RCB.