Lactacidemia in two different weight training models

The knowledge of the physiological aspects in the execution of the training in the bodybuilding is important to improve the training; being the lactate concentration an important marker applied in several types of exercises. Some studies have evaluated lactacidemia and training models but did not use squatting in their protocols. The aim of the study was to analyze blood lactate concentration in free squat exercise training in two training models: strength and resistance. Experimental study with a sample of five men of 24 ± 4.6 years, physically active and practicing for at least one year, with no history of orthopedic and cardiovascular problems. The tests were performed in two days, in the strength session the volunteers performed 12 sets, 6 to 12 maximal repetitions and in the resistance session 12 series, 13 to 20 maximum repetitions. In both tests the interval was 1 minute and 30 seconds between sets and 2 minutes every 4 sets. Blood lactate was collected at rest, during and after the test. No significant differences were found in the lactate concentration during and after the tests in the strength training and the resistance training. However, the lactacidemia variation between the first and last collection presented a significantly higher result in strength training. We conclude that the models of strength and resistance training, in the free squat exercise, do not present significant differences in lactate concentration during and after the tests. The total lactacidemia variation was greater in strength training

Acute effect of sodium bicarbonate supplementation by resistant training practices

Currently, the use of sodium bicarbonate (SB) as an ergogenic supplement has been linked to improved performance in several high-intensity and short time interval modalities because it is a natural buffer of the body fluids of the human body. This study aimed to evaluate the acute effect of SB supplementation on muscle strength endurance of resistance training practitioners. Crossover clinical trial, placebo-controlled (PL), and single-masked, included 10 trained adult men. The maximum repetition (1RM) and exhaustion tests with 80% 1RM were performed in the extensor chair and direct thread. In all sessions, the volunteers were verbally stimulated, the total maximum repetitions in the exercises and the blood lactate concentration were measured. SB was supplemented at a dose of 0.3 g/kg body mass. Statistical analysis was performed using SPSS version 25.0. The Shapiro–Wilk test was used to evaluate the normality of the data, and the Student’s t-test was used for independent and paired samples. The size of the Cohen’s effect was calculated, and the significance level was set at p 1.00). SB supplementation by endurance training practitioners induces blood alkalosis, which reduces fatigue and possibly improves muscle strength endurance. Keywords: resistance exercise, ergogenic, metabolic acidosis, muscular fatigue, performance

Association between obesity and knee osteoarthritis in users of brazilian unified national health system

Verify possible associations between obesity and knee OA in users of Brazilian Unified National Health System (Sistema Único de Saúde - SUS) of primary care network in Catalão-GO, Brazil. This is an observational study conducted in 2014 and 2015. A total of 81 volunteers from the Basic Attention Network in the city of Catalão, with body mass index (BMI) over 30 kg/m2 in both sexes, age between 40 and 60 years, and OA on radiological examination of the knee. Obesity was classified according to BMI. The diagnosis of osteoarthritis (OA) was made clinically and by radiography according to Kellgren radiological classification. The level of physical activity was assessed using the Baecke questionnaire and the Gordon Functional Classification. The volunteers underwent an anthropometric evaluation and physical examination with inspection and palpation of the joint and subsequent radiological examination of the knee. The volunteers answered a questionnaire on the level of physical activity and functional classification. Data analysis was performed using Fisher’s exact test or chi-square test was used for comparisons of two proportions. In comparisons of continuous variables, Student’s t-test or the nonparametric Wilcoxon-Mann-Whitney test was used. The level of significance was set to 5%. Practice of regular physical exercise decreases functional impairment in obese individuals with knee OA. The weight variable demonstrated a strong association with the severity of OA and degree of functionality of patients. Obesity and OA durations and lack of patient guidance are variables that may contribute to the progression of knee OA. Although the incidence among men is lower, they are more severely affected and anthropometric evaluation and physical examination are an efficacy implementations for Brazilian users of SUS

Effects of high-intensity interval training (HIIT) on heart rate variability in runners

Introduction: Running is among the most popular physical sports activities in the world. For the best performance and recovery of athletes, the training program must be well structured and encourage ideal adaptations to the training load. Evidence supports the positive effect of exercise programs based on High Intensity Interval Training (HIIT) to improve the physical performance of running athletes. Measures of heart rate variability (HRV) have been used to identify changes in autonomic regulation induced by training. Being a useful tool and able to monitor the responses to training loads, physical conditioning or overreaching in athletes during the competitive period or not. Objective: To analysis the HRV and performance of runners submitted to a HIIT protocol. Methods: Eleven runners participated in the study, aged between 31± 5.78 years, well trained with an average experience of 10.23±6.11 years and best time in a running test in a distance of 5 km of 16.94±1.82 minutes. The Maximum Incremental Test was performed on a treadmill, before and after the training program, to calculate the Maximum Aerobic Speed (VAM). After a previous warm-up, the test started at a speed of 10 km/h with an increment of 1 km/h of load every 2 minutes, without pauses between stages. The training lasted four weeks, with two weekly sessions, with the training intensity being readjusted with progressive loads each week. The stimuli were for 1 minute at the speed corresponding to % of VAM, followed by 1 minute of active recovery at 50% of %VAM, until voluntary exhaustion or up to the established ceiling of maximum 90 minutes for training sessions. RR Interval data were recorded at rest by the POLAR® RS800cx heart rate monitor, at 4 different times: before the initial maximum incremental test (PRE HIIT), before the first training session of week 3 (110% of VAM), before the first week 4 training session (Taper) and before the final incremental test (POST HIIT). HRV analyses were performed using Kubios® software in time domains, non-linear parameters and HRV overview parameters. Statistical analysis was performed using the following tests: Student's t (VO2 max and VAM); One Way ANOVA (rest HRV) and Tukey and Dunn post hoc multiple comparisons. Results: We evidenced positive responses to the proposed training protocol, with maintenance of cardiorespiratory fitness (VO2 max., VAM) and HRV at rest. We observed an adaptation of the cardiac autonomic modulation to the training load, with a reduction in the values of the HRV variables at 110% VAM and Taper moments, and an increase in the POST HIIT moment, approaching the values obtained in the PRE HIIT. Statistically significant differences were observed with p<0.05 in the indices: SDNN(ms): reduced in 110% VAM (34.93±15.87) and Taper (34.29±12.83) compared to PRE HIIT (57.34 ±36.72); RMSSD(ms): reduced in Taper (36.04±13.43) compared to POST HIIT (49.67±19.35); SD2(ms): reduced in Taper (40.05±18.15) compared to PRE HIIT (68.11±43.97). Conclusion: The HRV of runners is sensitive to the effects of HIIT, being efficient to monitor cardiac and autonomic regulation adjusts the training load. We also evidence that HIIT is efficient for the maintenance of the athletes' performance.Dissertação (Mestrado)Introdução: A corrida está entre as atividades físicas esportivas mais populares do mundo. Para o melhor desempenho e recuperação dos atletas o programa de treinamento deve ser bem estruturado e estimular adaptações ideais à carga de treinamento. Evidências apoiam o efeito positivo dos programas de exercícios baseados no Treinamento Intervalado de Alta Intensidade (HIIT) para melhorar o desempenho físico de atletas de corrida. As medidas de variabilidade da frequência cardíaca (VFC) vêm sendo utilizadas para identificar as mudanças na regulação autonômica induzidas pelo treinamento. Sendo uma ferramenta útil e capaz de monitorar as respostas às cargas de treinamento, condicionamento físico ou overreaching em atletas durante o período competitivo ou não. Objetivo: Analisar a VFC e o desempenho de corredores submetidos a um protocolo de HIIT. Métodos: Participaram do estudo onze corredores, com idade entre 31± 5,78 anos, bem treinado com experiência média de 10.23±6.11 anos e melhor tempo em prova de corrida na distância de 5 km de 16.94±1.82 minutos. Foi realizado Teste Incremental Máximo em esteira rolante, antes e após o programa de treinamento, para o cálculo da velocidade aeróbia máxima (VAM). Após um aquecimento prévio, o teste iniciou-se na velocidade de 10 km/h com incremento de 1 km/h de carga a cada 2 minutos, sem pausas entre os estágios. O treinamento teve duração de quatro semanas, com duas sessões semanais, sendo reajustada a intensidade do treino com cargas progressivas a cada semana. Os estímulos foram de 1 minuto na velocidade correspondente a % da VAM, seguidos por 1 minuto de recuperação ativa a 50% da %VAM, até a exaustão voluntária ou até o teto estabelecido de 90 minutos máximos para as sessões de treino. Os dados de Intervalo R-R foram registrados em repouso pelo cardiofrequencímetro POLAR® RS800cx, em 4 momentos distintos: antes do teste incremental máximo inicial (PRÉ HIIT), antes da primeira sessão de treino da semana 3 (110% da VAM), antes da primeira sessão de treino da semana 4 (Taper) e antes do teste incremental final (PÓS HIIT). As análises da VFC foram realizadas pelo software Kubios® nos domínios do tempo, parâmetros não lineares e parâmetros de visão geral da VFC. A análise estatística foi realizada pelos testes: t de Student (VO2 máx. e VAM); ANOVA One Way (VFC de repouso) e post hoc de Tukey e Dunn de comparações múltiplas. Resultados: Evidenciamos respostas positivas ao protocolo de treinamento proposto, com manutenção da aptidão cardiorrespiratória (VO2 máx., VAM) e da VFC de repouso. Observamos uma adaptação da modulação autonômica cardíaca à carga de treinamento, com redução dos valores das variáveis de VFC nos momentos 110% VAM e Taper, e aumento no momento PÓS HIIT, aproximando-se dos valores obtidos no PRÉ HIIT. Foram observadas diferenças estatísticas significativas com p<0,05 nos índices: SDNN(ms): reduziu no 110% VAM (34,93±15,87) e Taper (34,29±12,83) comparado com o PRÉ HIIT (57,34±36,72); RMSSD(ms): reduziu no Taper (36,04±13,43) comparado com o PÓS HIIT (49,67±19,35); SD2(ms): reduziu no Taper (40,05±18,15) comparado com o PRÉ HIIT (68,11±43,97). Conclusão: A VFC de corredores é sensível aos efeitos do HIIT, sendo eficiente para monitorar a regulação autonômica cardíaca e ajustar a carga de treinamento. Evidenciamos também que o HIIT é eficiente para a manutenção do desempenho dos atletas.2023-11-1

Um novo método fotogramétrico adequado a análises biomecânicas: comparação com o método DLT (transformação Linear Direta)

O presente estudo teve por objetivo descrever e obter dados, para fins de comparação, de dois métodos fotograméticos que possibilitam a análise especial em estudos biomecânicos, utilizando-se câmeras não-métricas: o método desenvolvido por Fonseca &amp; Ávila (1991) e o método da Transformação Liner Direta (DLT) elaborado por Abdel-Aziz &amp; Karara (1971). Através da obtenção das coordenadas espaciais de 25 pontos distribuídos no espaço, segundo cada método, foi possível compará-los entre si e com as médias das coordenadas X, Y e Z, previamente medidas, utilizando-se análise de variância e regressão linear. Os resultados indicaram não haver diferença estatisticamente significante entre as médias das coordenadas em relação aos eixos X, Y ou Z, para qualquer um dos métodos, notando-se, no entanto, uma maior precisão nos resultados do Método DLT. A regressão linear mostrou uma elevada correlação entre erros absolutos, variações no valor da distância focal e variações no fator de aplicação, como esperado, tendo-se observado maior influência deste último com relação à precisão no cálculo das coordenadas. Acredita-se que o método Fonseca &amp; Ávila possa ser uma alternativa quando o método DLT não puder ser empregado

Respiratory support in patients with severe COVID-19 in the International Severe Acute Respiratory and Emerging Infection (ISARIC) COVID-19 study: a prospective, multinational, observational study

Background: Up to 30% of hospitalised patients with COVID-19 require advanced respiratory support, including high-flow nasal cannulas (HFNC), non-invasive mechanical ventilation (NIV), or invasive mechanical ventilation (IMV). We aimed to describe the clinical characteristics, outcomes and risk factors for failing non-invasive respiratory support in patients treated with severe COVID-19 during the first two years of the pandemic in high-income countries (HICs) and low middle-income countries (LMICs). Methods: This is a multinational, multicentre, prospective cohort study embedded in the ISARIC-WHO COVID-19 Clinical Characterisation Protocol. Patients with laboratory-confirmed SARS-CoV-2 infection who required hospital admission were recruited prospectively. Patients treated with HFNC, NIV, or IMV within the first 24 h of hospital admission were included in this study. Descriptive statistics, random forest, and logistic regression analyses were used to describe clinical characteristics and compare clinical outcomes among patients treated with the different types of advanced respiratory support. Results: A total of 66,565 patients were included in this study. Overall, 82.6% of patients were treated in HIC, and 40.6% were admitted to the hospital during the first pandemic wave. During the first 24 h after hospital admission, patients in HICs were more frequently treated with HFNC (48.0%), followed by NIV (38.6%) and IMV (13.4%). In contrast, patients admitted in lower- and middle-income countries (LMICs) were less frequently treated with HFNC (16.1%) and the majority received IMV (59.1%). The failure rate of non-invasive respiratory support (i.e. HFNC or NIV) was 15.5%, of which 71.2% were from HIC and 28.8% from LMIC. The variables most strongly associated with non-invasive ventilation failure, defined as progression to IMV, were high leukocyte counts at hospital admission (OR [95%CI]; 5.86 [4.83-7.10]), treatment in an LMIC (OR [95%CI]; 2.04 [1.97-2.11]), and tachypnoea at hospital admission (OR [95%CI]; 1.16 [1.14-1.18]). Patients who failed HFNC/NIV had a higher 28-day fatality ratio (OR [95%CI]; 1.27 [1.25-1.30]). Conclusions: In the present international cohort, the most frequently used advanced respiratory support was the HFNC. However, IMV was used more often in LMIC. Higher leucocyte count, tachypnoea, and treatment in LMIC were risk factors for HFNC/NIV failure. HFNC/NIV failure was related to worse clinical outcomes, such as 28-day mortality. Trial registration This is a prospective observational study; therefore, no health care interventions were applied to participants, and trial registration is not applicable

ISARIC-COVID-19 dataset: A Prospective, Standardized, Global Dataset of Patients Hospitalized with COVID-19

The International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) COVID-19 dataset is one of the largest international databases of prospectively collected clinical data on people hospitalized with COVID-19. This dataset was compiled during the COVID-19 pandemic by a network of hospitals that collect data using the ISARIC-World Health Organization Clinical Characterization Protocol and data tools. The database includes data from more than 705,000 patients, collected in more than 60 countries and 1,500 centres worldwide. Patient data are available from acute hospital admissions with COVID-19 and outpatient follow-ups. The data include signs and symptoms, pre-existing comorbidities, vital signs, chronic and acute treatments, complications, dates of hospitalization and discharge, mortality, viral strains, vaccination status, and other data. Here, we present the dataset characteristics, explain its architecture and how to gain access, and provide tools to facilitate its use

Respiratory support in patients with severe COVID-19 in the International Severe Acute Respiratory and Emerging Infection (ISARIC) COVID-19 study: a prospective, multinational, observational study

Background: Up to 30% of hospitalised patients with COVID-19 require advanced respiratory support, including high-flow nasal cannulas (HFNC), non-invasive mechanical ventilation (NIV), or invasive mechanical ventilation (IMV). We aimed to describe the clinical characteristics, outcomes and risk factors for failing non-invasive respiratory support in patients treated with severe COVID-19 during the first two years of the pandemic in high-income countries (HICs) and low middle-income countries (LMICs). Methods: This is a multinational, multicentre, prospective cohort study embedded in the ISARIC-WHO COVID-19 Clinical Characterisation Protocol. Patients with laboratory-confirmed SARS-CoV-2 infection who required hospital admission were recruited prospectively. Patients treated with HFNC, NIV, or IMV within the first 24 h of hospital admission were included in this study. Descriptive statistics, random forest, and logistic regression analyses were used to describe clinical characteristics and compare clinical outcomes among patients treated with the different types of advanced respiratory support. Results: A total of 66,565 patients were included in this study. Overall, 82.6% of patients were treated in HIC, and 40.6% were admitted to the hospital during the first pandemic wave. During the first 24 h after hospital admission, patients in HICs were more frequently treated with HFNC (48.0%), followed by NIV (38.6%) and IMV (13.4%). In contrast, patients admitted in lower- and middle-income countries (LMICs) were less frequently treated with HFNC (16.1%) and the majority received IMV (59.1%). The failure rate of non-invasive respiratory support (i.e. HFNC or NIV) was 15.5%, of which 71.2% were from HIC and 28.8% from LMIC. The variables most strongly associated with non-invasive ventilation failure, defined as progression to IMV, were high leukocyte counts at hospital admission (OR [95%CI]; 5.86 [4.83–7.10]), treatment in an LMIC (OR [95%CI]; 2.04 [1.97–2.11]), and tachypnoea at hospital admission (OR [95%CI]; 1.16 [1.14–1.18]). Patients who failed HFNC/NIV had a higher 28-day fatality ratio (OR [95%CI]; 1.27 [1.25–1.30]). Conclusions: In the present international cohort, the most frequently used advanced respiratory support was the HFNC. However, IMV was used more often in LMIC. Higher leucocyte count, tachypnoea, and treatment in LMIC were risk factors for HFNC/NIV failure. HFNC/NIV failure was related to worse clinical outcomes, such as 28-day mortality. Trial registration This is a prospective observational study; therefore, no health care interventions were applied to participants, and trial registration is not applicable

Characteristics and outcomes of an international cohort of 600 000 hospitalized patients with COVID-19

Background: We describe demographic features, treatments and clinical outcomes in the International Severe Acute Respiratory and emerging Infection Consortium (ISARIC) COVID-19 cohort, one of the world's largest international, standardized data sets concerning hospitalized patients. Methods: The data set analysed includes COVID-19 patients hospitalized between January 2020 and January 2022 in 52 countries. We investigated how symptoms on admission, co-morbidities, risk factors and treatments varied by age, sex and other characteristics. We used Cox regression models to investigate associations between demographics, symptoms, co-morbidities and other factors with risk of death, admission to an intensive care unit (ICU) and invasive mechanical ventilation (IMV). Results: Data were available for 689 572 patients with laboratory-confirmed (91.1%) or clinically diagnosed (8.9%) SARS-CoV-2 infection from 52 countries. Age [adjusted hazard ratio per 10 years 1.49 (95% CI 1.48, 1.49)] and male sex [1.23 (1.21, 1.24)] were associated with a higher risk of death. Rates of admission to an ICU and use of IMV increased with age up to age 60&nbsp;years then dropped. Symptoms, co-morbidities and treatments varied by age and had varied associations with clinical outcomes. The case-fatality ratio varied by country partly due to differences in the clinical characteristics of recruited patients and was on average 21.5%. Conclusions: Age was the strongest determinant of risk of death, with a ∼30-fold difference between the oldest and youngest groups; each of the co-morbidities included was associated with up to an almost 2-fold increase in risk. Smoking and obesity were also associated with a higher risk of death.&nbsp;The size of our international database and the standardized data collection method make this study a comprehensive international description of COVID-19 clinical features. Our findings may inform strategies that involve prioritization of patients hospitalized with COVID-19 who have a higher risk of death