Efecto agudo de los entrenamientos de fuerza, velocidad, pliometría y velocidad contra resistencia en la carrera de velocidad / Acute effect of strength, speed, plyometric, and resisted sprint trainings on sprinting

Resumen La velocidad juega un papel fundamental en el rendimiento deportivo, tanto en deportes individuales como colectivos. Los objetivos de este estudio son: a) determinar el efecto agudo de los tipos de entrenamiento de fuerza, velocidad, pliometría y velocidad contra resistencia en la carrera de velocidad y sus fases y b) realizar el análisis del efecto agudo de estos tipos de entrenamiento de manera individual. Once velocistas (edad promedio de 21.8 años ± 3.04, talla de 1.764 m ± 0.062 y peso de 69.645 kg ± 4.946), con experiencia como velocistas realizaron cinco tratamientos agudos (F, V, P, VR y control), para los cuales se aleatorizó el orden. Para cada tratamiento, realizaron un pre test y un post test de 100 metros con mediciones de intervalos cada 20 metros. Se realizaron 2 análisis de varianza (ANOVA) de medidas repetidas de 2 y 3 vías, con el objetivo de analizar el efecto de los tratamientos en el tiempo total de carrera y en cada uno de los intervalos de la carrera de velocidad, respectivamente. También, se realizó un análisis individual, utilizando estadísticos descriptivos y gráficos. No hubo interacción significativa entre las mediciones y los tipos de entrenamiento (F = 1.733 p = .162), ni entre las mediciones, los tipos de entrenamiento y los intervalos de distancia (F = 0.569 p = .903). En el análisis individual, se observa como los cambios en la velocidad según el tipo de tratamiento varían entre sujetos, siendo el tratamiento de velocidad con el que más sujetos mejoran.

Abstract Speed plays a key role in performance in both collective and individual sports. The objectives of this study are: a) to determine the acute effect of strength, speed, plyometric, and resisted sprint trainings in sprinting and its phases, and b) to analyze the acute effect of these types of training on an individual manner. Eleven experienced sprinters (mean age 21.8 ± 3.04, height 1.764 m ± 0.062, and weight 69.645 kg ± 4.946) participated in five training sessions (S, SP, P, RS, and control) assigned in a random order. For each treatment, 100 meter-pre and post-tests were conducted with interval measurements every 20 meters. Two-way and three-way variance analyses (ANOVA) of repeated measurements were conducted to analyze the effect of the types of training on the total race time and in each interval, respectively. In addition, descriptive statistics and graphs were used for an individual analysis. For the group analysis, no significant interaction was found between measurements and the types of training (F = 1.733 p = .162) or between measurements, types of training, and distance intervals (F = 0.569 p = .903). However, in the individual analysis, changes in speed based on the type of treatment vary between subjects, being speed the treatment that shows more improvement in subjects.

Resumo A velocidade tem um papel fundamental no desempenho esportivo, tanto em esportes individuais quanto coletivos. Este estudo tem como objetivo: a) determinar o efeito agudo dos tipos de treinamento de força, velocidade, pliometria e velocidade contrarresistência na corrida de velocidade e suas fases e b) realizar a análise do efeito agudo destes tipos de treinamento de maneira individual. Onze velocistas (idade média de 21,8 anos ± 3,04, altura de 1,764 m ± 0,062 e peso de 69,645 kg ± 4,946), com experiência como velocistas realizaram cinco tratamentos agudos (F, V, P, VR e controle), para os quais se aleatorizou a ordem. Para cada tratamento, foram realizados um pré-teste e um pós-teste de 100 metros com medições de intervalos a cada 20 metros. Foram realizadas 2 análises de variância (ANOVA) de medidas repetidas de 2 e 3 vias, a fim de analisar o efeito dos tratamentos no tempo total de corrida e em cada um dos intervalos da corrida de velocidade, respectivamente. Também, foi realizada uma análise individual, utilizando estatísticos descritivos e gráficos. Não houve interação significativa entre as medições e os tipos de treinamento (F = 1,733 p = 0,162), nem entre as medições, os tipos de treinamento e os intervalos de distância (F = 0,569 p = 0,903). Na análise individual, observa-se como as mudanças na velocidade segundo o tipo de tratamento variam entre sujeitos, sendo o tratamento de velocidade com o que mais sujeitos melhoram.

Efeito agudo da corrida aeróbica na pressão arterial em jovens adultos normotensos / Acute effects of aerobic running on blood pressure in young normotens adults

RESUMO O objetivo do presente estudo foi investigar o efeito hipotensivo induzido pela corrida aeróbica em jovens adultos. Trinta e um indivíduos (18 mulheres e 13 homens) foram submetidos a uma avaliação antropométrica e o protocolo de corrida proposto em uma esteira ergométrica durante 40 min entre 60 a 70% da frequência cardíaca de reserva. Realizaram-se medidas da pressão arterial sistólica (PAS) e pressão arterial diastólica (PAD) que posteriormente foram comparados antes e ao final do protocolo de corrida através do teste t de Student para as variáveis dependentes. Todos os testes foram assumidos com α = 0,05. Em comparação com a PAS antes (127,1 ± 11,5 mmHg) e após (119,9 ± 10,2 mmHg) a corrida, os resultados obtidos evidenciaram uma diminuição da pressão arterial sistólica, o qual resultou uma diferença média de -7,2 ± 6,2 mmHg, demonstrando uma diferença significativa (p = 0,00001). Entretanto, na PAD antes (73,6 ± 8,6 mmHg) e após (72,5 ± 7,8 mmHg) não demonstrou uma diferença significativa (p = 0,36) como efeito agudo na diminuição após a corrida. Portanto, conclui-se que a corrida em moderada intensidade e longa duração pode ser auxiliado no tratamento não farmacológico da hipertensão arterial e como melhoria na saúde cardiovascular.

ABSTRACT The aim of the present study was to investigate the acute effects of blood pressure induced by moderate intensity aerobic exercise in young adults. Thirty-one individuals (18 women and 13 men) were submitted an anthropometric evaluation and a 40-min running protocol between 60% and 70% of the reserve heart rate. Hemodynamic measurements, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were carried out before and after the running protocol through Student's t-test for the dependent variables. All tests assumed α = 0.05. Significant differences were recorded between SBP before (127.1 ± 11.5 mmHg) and after (119.9 ± 10.2 mmHg) the running protocol. The results showed a decrease in systolic blood pressure, which resulted in a mean difference of -7.2 ± 6.2 mmHg, demonstrating a significant difference (p = 0.00001). However, in the DBP before (73.6 ± 8.6 mmHg) and after (72.5 ± 7.8 mmHg) no showing a significant difference (p = 0.36) as an acute effect on the decrease the running protocol. In conclusion, that moderate intensity and long duration running exercise can be aided in the non-pharmacological treatment of arterial hypertension and as an improvement in cardiovascular health.

Fecundity Studies Of Andrographis Paniculata On Drosophila Melanogaster

Objective: Andrographis paniculata is widely used in Asia for various medicinal purposes. The plant has a major bioactive chemical constituent Andrographolide, which exhibits various essential pharmacological properties. Recently, to enhance immunity against viral fevers especially dengue viral fever during monsoon season, Tamil Nadu state government has advised rural health centres to provide a tea or kashayam made from a mixture containing this plant leaf along with selected plant roots and leaves. However, there is concern among the general public population that this plant extract may have a negative impact on potency. This study is being done to investigate the toxic effects of Andrographis paniculata on fecundity and physiological properties of Drosophila melanogaster. Methods: The flies were treated and mated in pure and mixed form of Andrographis paniculata separately. Results: The results were obtained in the form of egg count, which was compared to control and the conclusion was obtained that Andrographis paniculata might affect the fecundity and at the same time, it was observed that the developmental span from an egg to an adult fly increased upon treatment in successive generations. More importantly, the effect of pure form plant on the fecundity was found to be significant, while that of the mixed form was not. On mating a treated male with an untreated female and an untreated male with a treated female when the treatment is being discontinued, it can be very well seen that there is no effect on the fecundity of the flies. Conclusion: Since the continuity of the treatment played a major role on the effect of fecundity, highlighting the importance of the period of treatment and the exposure time of the compound on the fly system, therefore this research suggests that the conception of tea or kashayam extracted from mixed plant content could not have the same effect as the similar concentration of pure Andrographis paniculata and it does not have any acute effect on the fecundity when being consumed over a short period of time in Drosophila melanogaster model.

Acute Effects of Exercise on Blood Pressure: A Meta-Analytic Investigation / Efeito Agudo do Exercício Sobre a Pressão Arterial: Uma Investigação Metanalítica

Abstract Hypertension affects 25% of the world's population and is considered a risk factor for cardiovascular disorders and other diseases. The aim of this study was to examine the evidence regarding the acute effect of exercise on blood pressure (BP) using meta-analytic measures. Sixty-five studies were compared using effect sizes (ES), and heterogeneity and Z tests to determine whether the ES were different from zero. The mean corrected global ES for exercise conditions were -0.56 (-4.80 mmHg) for systolic BP (sBP) and -0.44 (-3.19 mmHg) for diastolic BP (dBP; z ≠ 0 for all; p < 0.05). The reduction in BP was significant regardless of the participant's initial BP level, gender, physical activity level, antihypertensive drug intake, type of BP measurement, time of day in which the BP was measured, type of exercise performed, and exercise training program (p < 0.05 for all). ANOVA tests revealed that BP reductions were greater if participants were males, not receiving antihypertensive medication, physically active, and if the exercise performed was jogging. A significant inverse correlation was found between age and BP ES, body mass index (BMI) and sBP ES, duration of the exercise's session and sBP ES, and between the number of sets performed in the resistance exercise program and sBP ES (p < 0.05). Regardless of the characteristics of the participants and exercise, there was a reduction in BP in the hours following an exercise session. However, the hypotensive effect was greater when the exercise was performed as a preventive strategy in those physically active and without antihypertensive medication.

Resumo A hipertensão arterial afeta 25% da população mundial e é considerada um fator de risco para distúrbios cardiovasculares e outras doenças. O objetivo deste estudo foi examinar as evidências sobre o efeito agudo do exercício sobre a pressão arterial (PA) utilizando medidas metanalíticas. Sessenta e cinco estudos foram comparados com tamanho de efeito (TE), testes de heterogeneidade, e teste Z para determinar se os TE eram diferentes de zero. A média dos TE globais corrigida para as condições do exercício foram -0,56 (-4,80 mmHg) para a PA sistólica (PAs) e -0,44 (-3,19 mmHg) para a PA diastólica (PAd; z ≠ 0 para todos; p < 0,05). A redução da PA foi significativa independente da PA inicial do participante, sexo, nível de atividade física, ingestão de medicamentos anti-hipertensivos, tipo de medição da PA, hora do dia na qual a PA foi medida, tipo de exercício realizado, e programa de treinamento (p < 0,05 para todos). Testes ANOVA revelaram que as reduções da PA eram maiores se os participantes eram do sexo masculino, não recebiam medicação anti-hipertensiva, eram fisicamente ativos e se o exercício realizado era jogging. Uma correlação inversa significativa foi encontrada entre idade e TE da PA, índice de massa corporal (IMC) e TE da PAs, duração da sessão de exercício e TE da PAs, e número de séries realizadas no programa de exercícios de resistência e TE da PAs (p < 0,05). Independente das características dos participantes e do exercício, houve uma redução na PA poucas horas após uma sessão de exercícios. No entanto, o efeito hipotensor foi maior quando o exercício foi realizado como uma estratégia preventiva em pessoas fisicamente ativas e sem medicação anti-hipertensiva.

Some Biochemical Effects of Methanolic Extract of Afzelia africana Seed in Rats Following Single or Repeated Carbon Tetrachloride Intoxication.

Aim: To establish the in vivo effects of the methanolic extract of Afzelia africana seed on CCl4- induced organ damage on some biochemical parameters. Methods: The rats were divided into 7 groups of 5 rats each. In the single administration experiment, rats were intraperitoneally pre-treated with the extract (10mg/kg) for two days before CCl4 intoxication at 0.6ml/kg. In the repeated intoxication experiment, rats were administered the extract (5mg/kg) by intraperitoneal injection for 10 consecutive days, and CCl4 (0.6ml/kg) 72 hourly intervals for 10 days. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin (conjugated and total) were analyzed for hepatoprotective effect, while urea and creatinine were used to evaluate kidney function. Results: Data obtained showed significant reduction (P=.05) in the activities of ALT and AST, as well as in levels of bilirubin, urea and creatinine in the Afzelia africana extracttreated rats compared to the CCl4 control. Conclusion: These results indicate that the seeds of A. africana contain constituents that could protect the kidney and liver and ameliorate them from both acute and chronic injuries.

Acute Effect of Cigarette Smoking On HRV in Current Cigarette Smokers.

Background:Cigarette smoking induced increased sympathetic activity is one of the major independent risk factor for cardiac morbidity and mortality. Objective:To assess acute effects of smoking on neuro cardiovascular regulation by analysis of time domain measures of HRV in current regular healthy male cigarette smoker. Methods:This comparative analytical study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka from July 2011 to June 2012. 120 apparently healthy male current regular cigarette smoker aged 20-55 years were participated in the study group. Age and BMI matched 70 apparently healthy male non smoker subjects were studied as control. To observe the acute effects data were recorded 5 and 30 min after finishing a cigarette. Time domain measures of HRV were recorded by a RMS digital polyrite D. Statistical analysis was done by independent sample t test and paired sample t test.Results: Resting pulse rate, SBP, DBP, mean heart rate were significantly higher (p<0.001) and mean R-R interval, SDNN, RMSSD and total power were significantly lower (p<0.001) in all smokers in comparison to those of healthy control.In addition, all time domain parameters were significantly decreased from their corresponding baseline value just 5 minutes after smoking and returned close to their baseline value after 30 minutes of smoking but it remained significantly lower than control value. Conclusion: The result of this study concludes that cigarette smoking had acute effect on cardiac autonomic function causing depressed vagal activity and overbalance of sympathetic function..

A Time-series Study for Acute Effect of Air Pollution on Mortality in Patients With Cardio-cerebral Vascular Disease in Tianjin City / 中国循环杂志

Objective: To explore the acute effect of air pollution on mortality for patients with cardio cerebral vascular disease and to provide the basis for disease prevention and control. Methods: The Mortality for patients with cardio cerebral vascular disease from 2001-01 to 2009-12 was from Tianjin Centers for Disease Control and Prevention, the meteorological and air pollution data were from Tianjin meteorological bureau and Tianjin environmental monitoring station respectively. The Single and multiple generalized additive model (GAM) extended poisson regression analysis was performed to calculate the relationship between air pollution and cardio-cerebral vascular disease mortality by controlling the time trends, weather, the day of week and air population. Results: Results: Single GAM analysis indicated that when the effect of SO2, NO2 and PM10 in the air reached the maximum in the day, the RR values for the mortality in patients with cardio-cerebral vascular disease increased 1.13%[95%CI (0.76-1.51)%], 0.78% [95%CI ( 0.41-1.15)%] and 0.61% [95%CI ( 0.51-0.71)%] respectively; when the average concentration of SO2, NO2 and PM10 increasing 10μg/m3 per day, after 0-5 days, the RR values for the mortality elevated 0.70% [95%CI (0.47-0.94)%], 0.51% [95%CI (0.27-0.74)%] and 0.16% [95%CI (0.06-0.27)%] respectively. Multiple GAM analysis presented that when SO2, NO2 and PM10 increasing 10 μg/m3 per day, the RR values for the mortality elevated 0.77% [95%CI (0.58-0.97)%], 0.41% [95%CI (0.05-0.78) %] and 0.38% [95%CI (0.12-0.64%)%] respectively. Conclusion: The air pollution could increase the mortality risk in patients with cardio-cerebral vascular disease, it is necessary to establish the prevention system in order to decrease the mortality risk in those patients.

Metanálise dos efeitos agudos do alongamento na realização de corridas curtas de alta intensidade / Meta-analysis of the acute effects of stretching on high intensity sprint performance

Informações das pesquisas explorando efeitos do alongamento no desempenho em corridas curtas de alta intensidade (CCAI) são controversas. Com isso, esta metanálise objetivou examinar os desfechos decorrentes da execução de diferentes protocolos de alongamentos, prévios à execução de CCAI. A pesquisa foi realizada em diversas bases de dados, usando combinações dos seguintes termos de referência: "sprint" e "stretching". Selecionaram-se estudos com pessoas do sexo masculino e idade superior a 16 anos, sem restrição de modalidade, nível de aptidão física e procedimentos de avaliação utilizados. Após diferentes depurações, localizaram-se 11 investigações como apropriadas para análises, das quais resultaram 62 situações para serem estudadas. Como variáveis dependentes, consideraram-se o Tamanho de Efeito (TE) e o Delta Percentual (Δ por cento), e, como fatores, delineamento adotado, tipo de alongamento, protocolo de avaliação, número de séries, modalidade esportiva, nível de aptidão e prática pregressa de alongamento. Os resultados sugerem que: a) alongamento dinâmico (AD) promove rendimento significativamente superior quando comparado ao alongamento estático (AE) (p < 0,001) ou misto (AM) (p < 0,002); b) há diferença no TE e no Δ por cento entre corridas com mudança de direção e corridas lineares (até 20 m, p = 0,003, e acima de 20 m, p < 0,009); c) realização de vários testes proporciona melhores resultados que aplicação de teste único após aquecer e alongar (p = 0,001); e d) executar série única de alongamento é menos prejudicial que duas (p = 0,016) e três séries (p < 0,001). Sendo assim, é possível a obtenção de pequena vantagem incorporando o AD em relação ao AE, AM ou ausência de estímulos para a execução de CCAI.

The literature on the effects of stretching on sprint performance is controversial. This meta-analysis aimed at examining the outcomes of the studies using different stretching protocols prior to sprint efforts. The search was conducted in several databases, using combinations of the following keywords: sprinting and stretching. Inclusion criteria included studies with males aged over 16 years irrespective of the sport, fitness level and assessment procedures performed. After the evaluation of the selected studies, 11 were considered appropriate for the analysis, resulting in 62 cases to be studied. The effect size (ES) and delta percentage (Δ percent) were considered as dependent variables. The study design, type of stretching, assessment protocol, number of sets, sport, fitness level and previous practice of stretching were considered as factors. The results suggest that: a) dynamic stretching (DS) significantly improves performance when compared to static (SS) (p < 0.001) or mixed (MS) (p < 0.002) stretching methods; b) there are significant differences in ES and Δ percent between runs with change of direction and linear races (up to 20 m, p = 0.003, and above 20 m, p < 0.009); c) performing multiple tests provides better results than a single test after the warm-up and stretch (p = 0.001), and d) performing a single bout of stretching is less harmful to performance than two (p = 0.016) and three (p < 0.001) bouts. Therefore, it is possible to obtain small gains in high-intensity sprinting performance by using DS when compared with SS, MS or no stimuli.

Chronic and Acute Effects of Work-related Factors on Heart Rate Variability / 대한산업의학회지

OBJECTIVES: Reduced heart rate variability (HRV) is one of the serious risk factors for heart diseases. We evaluated the acute and chronic effects of work-related factors on HRV. METHODS: The five-minute HRV of 85 male workers from an automobile assembly factory were measured at 9 A.M. (before-work) and at 5 P.M. (after-work). The workplace noise, temperature and physical workload levels were measured as work-related factors. We postulated that the HRV measured at beforework represents the chronic effects and the HRV measured at after-work represents the acute effects of work-related factors. We used generalized linear regression analysis with adjusting for the general characteristics and/or the morning HRV. RESULTS: The subjects exposed to noise or a hot environment showed increased HRV in the afternoon and decreased HRV in the morning. Machine oil and interpersonal conflict decreased the HRV in the morning, but other chemicals did not show any effect on the HRV. A physical workload decreased the HRV in both the morning and afternoon. CONCLUSION: The physical and chemical environment, psychosocial stress and a physical workload may affect the autonomic nerve system.

Effects of exercise intensity on circulating leukocyte subpopulations

<p><b>OBJECTIVES</b>The purpose of this study was to examine the relation between exercise intensity and immune function.</p><p><b>METHODS</b>Ten healthy young males underwent a constant work rate exercise of three levels, 90%, 80% and 70% ventilatory threshold (VT) work rate, for 20 min on a bicycle ergometer. These work rates were calculated for each individual based on his VT work rate obtained by the incremental exercise tests. Blood samples were collected before and after the exercise, and immune function indices were measured.</p><p><b>RESULTS</b>Compared with the obtained[Formula: see text] at[Formula: see text] in the incremental test, the[Formula: see text] with the exercise of 70% VT work rate was at a similar level and the one with the exercise of 90% or 80% VT work rate had a significantly greater value. The numbers of leukocytes and neutrophils significantly increased in the 90% and 70% VT work rate groups. In 80% VT work rate group, the CD4/CD8 ratio was significantly depressed. The CD16(+)CD57(-) (%), natural killer cell populations, had a tendency to increase at 80% VT work rate, and also the CD16(+)CD57(-) (%) had a similar tendency at 90% or 80% VT work rate.</p><p><b>CONCLUSIONS</b>This study shows that moderate exercise reaching or exceeding the VT level acutely affects T cell and NK cell subsets.</p>

Effects of Exercise Intensity on Circulating Leukocyte Subpopulations

Objectives: The purpose of this study was to examine the relation between exercise intensity and immune function. Methods: Ten healthy young males underwent a constant work rate exercise of three levels, 90%, 80% and 70% ventilatory threshold (VT) work rate, for 20 min on a bicycle ergometer. These work rates were calculated for each individual based on his VT work rate obtained by the incremental exercise tests. Blood samples were collected before and after the exercise, and immune function indices were measured. Results: Compared with the obtained Vo2 at VT (VTVo2) in the incremental test, the Vo2 with the exercise of 70% VT work rate was at a similar level and the one with the exercise of 90% or 80% VT work rate had a significantly greater value. The numbers of leukocytes and neutrophils significantly increased in the 90% and 70% VT work rate groups. In 80% VT work rate group, the CD4/CD8 ratio was significantly depressed. The CD16+CD57− (%), natural killer cell populations, had a tendency to increase at 80% VT work rate, and also the CD16+CD57 + (%) had a similar tendency at 90% or 80% VT work rate. Conclusions: This study shows that moderate exercise reaching or exceeding the VT level acutely affects T cell and NK cell subsets.

Difference of Immediate Effect between Mao-bushi-saishin-to Extract Granule and Its Extract Capsule on Allergic Nasal Obstruction Shown in Two Adults / 日本東洋医学雑誌

The author evaluated immediate effects of a single dose of Mao-bushi-saishin-to extract granules (TJ-127) and extract capsules (NC127) on allergic nasal obstruction using acoustic rhinometry in two adult male patients. In case 1, no apparent increase of right+left nasal cavity volume (NCV) was shown during a period of 95 minutes after the administration of NC127. However, an increase was noted 50 minutes after the administration of TJ-127. In case 2, NCV started increasing 15 minutes after the administration of TJ-127 and 50 minutes after the administration of NC127. The result indicates that Mao-bushi-saishin-to extract granules might take effect more quickly than extract capsules.