Protective effects of accumulated aerobic exercise in infarcted old rats / Efeitos protetores do exercício aeróbio acumulado em ratos idosos infartados

Background: Aerobic exercise exerts cardioprotective effects on myocardial infarction. However, there is lack of information about the possible protective effects of continuous or accumulated aerobic exercise performed prior to myocardial infarction in aging. Objective: To evaluate the preventive effects of continuous or accumulated aerobic exercise on physical capacity, pulmonary congestion and ventricular weight in rats submitted to myocardial infarction. Methods: Old male Wistar rats were divided into four groups: sham control, sedentary infarcted, continuous aerobic exercise submitted to myocardial infarction, and accumulated aerobic exercise submitted to myocardial infarction. Body weight and maximum speed were evaluated at the beginning and at the end of the protocol. Trained groups performed continuous (1 h a day) or accumulated (30 minutes in the morning and 30 minutes in the afternoon) exercise. All groups, except the sham control, were submitted to myocardial infarction surgery at the end of the protocol. Heart, skeletal muscles, as well as wet and dry lung were weighed. The significance level in statistical analysis was established at p < 0.05. Results: Both continuous and accumulated exercise caused an increase in physical capacity in rats, as well as prevented its further impairment after myocardial infarction, and in the accumulated exercise group this prevention was greater. The continuous exercise group demonstrated an increase in lung water content, while the accumulated exercise group presented a reduction in body weight and an increase in left ventricle relative weight. Conclusion: In conclusion, the data of the present study indicate that accumulated aerobic exercise present a better protective effect than continuous aerobic training in the context of myocardial infarction and aging

Multicomponent exercise decreases blood pressure, heart rate and double product in normotensive and hypertensive older patients with high blood pressure / El ejercicio multicomponente disminuye los parámetros hemodinámicos en pacientes ancianos normotensos e hipertensos no controlados

Abstract Objective: The present study aimed to investigate the effects of a 6-month multicomponent exercise program on blood pressure, heart rate, and double product of uncontrolled and controlled normotensive and hypertensive older patients. Methods: The study included 183 subjects, 97 normotensives, of which 53 were controlled normotensives (CNS), and 44 uncontrolled normotensives (UNS), as well as 86 hypertensives, of which 43 were controlled hypertensives (CHS), and 43 uncontrolled hypertensives (UHS). Volunteers were recruited and blood pressure and heart rate measurements were made before and after a 6-month multicomponent exercise program. The program of physical exercise was performed twice a week for 26 weeks. The physical exercises program was based on functional and walking exercises. Exercise sessions were performed at moderate intensity. Results: The results indicated that UHS showed a marked decrease in systolic (−8.0 mmHg), diastolic (−11.1 mmHg), mean (−10.1 mmHg), and pulse pressures, heart rate (−6.8 bpm), and double product (−1640 bpm mmHg), when compared to baseline. Similarly, diastolic (−5.5 mmHg) and mean arterial (−4.8 mmHg) pressures were significantly decreased in UNS. Concomitantly, significant changes could be observed in the body mass index (−0.9 kg/m2;−1.5 kg/m2) and waist circumference (−3.3 cm; only UHS) of UNS and UHS, which may be associated with the changes observed in blood pressure. Conclusions: In conclusion, the data of the present study indicate that a 6-month multicomponent exercise program may lead to significant reductions in blood pressure, heart rate, and double product of normotensive and hypertensive patients with high blood pressure values.

Resumen Objetivo: El presente estudio tuvo como objetivo investigar los efectos de un programa de ejercicios multicomponente de 6 meses sobre la presión arterial, la frecuencia cardíaca y el doble producto de pacientes mayores hipertensos y normotensos (incontrolados y controlados). Método: 183 sujetos, 97 normotensos - 53 normotensos controlados (SNC) y 44 normotensos no controlados (SNU) - y 86 hipertensos - 43 hipertensos controlados (CHS) y 43 hipertensos no controlados (UHS) -, fueron reclutados y sometidos a evaluaciones (presión arterial y frecuencia cardíaca) antes y después de un programa de ejercicios multicomponente de 6 meses. El programa de ejercicio se realizó dos veces por semana durante 26 semanas. El programa de ejercicios físicos se basó en ejercicios funcionales y de caminar. Las sesiones de ejercicio se realizaron a intensidad moderada. Resultados: Los resultados indicaron que UHS presentó una marcada disminución en presión sistólica (−8.0 mmHg), diastólica (−11.1 mmHg), media (−10.1 mmHg) y de pulso, frecuencia cardíaca (−6.8 lpm) y doble producto (−1640 lpm mmHg) cuando se compara con la línea base. De manera similar, las presiones diastólica (−5.5 mmHg) y arterial media (−4.8 mmHg) se redu- jeron significativamente en los SNU. Concomitantemente, fue posible observar alteraciones significativas en el índice de masa corporal (−0.9 kg/m2; −1.5 kg/m2) y circunferencia de cintura (−3.3 cm, solo UHS) de UNS y UHS, lo que puede estar asociado con los cambios observados en la presión arterial. Conclusiones: En conclusión, los datos del presente estudio indican que un programa de ejercicio multicomponente de 6 meses puede provocar reducciones significativas en la presión arterial, frecuencia cardíaca y doble producto de pacientes normotensos e hipertensos con valores de presión arterial alta.

Exercise training on cardiovascular diseases: Role of animal models in the elucidation of the mechanisms

Abstract Cardiovascular diseases, which include hypertension, coronary artery disease/myocardial infarction and heart failure, are one of the major causes of disability and death worldwide. On the other hand, physical exercise acts in the preventionand treatment of these conditions. In fact, several experiments performed in human beings have demonstrated the efficiency of physical exercise to alter clinical signals observed in these diseases, such as high blood pressure and exercise intolerance. However, even if human studies demonstrated the clinical efficiency of physical exercise, most extensive mechanisms responsible for this phenomenon still have to be elucidated. In this sense, studies using animal models seem to be a good option to demonstrate such mechanisms. Therefore, the aims of the present study are describing the main pathophysiological characteristics of the animal models used in the study of cardiovascular diseases, as well as the main mechanismsassociated with the benefits of physical exercise.(AU)

POWERLIFTING: Entendendo a modalidade / POWERLIFTING: Understanding the modality

O objetivo do presente estudo foi entender a modalidade powerlifting associada aos aspectos morfofuncionais que envolvem a modalidade. Para isso, foi realizada uma revisão bibliográfica com busca de artigos que tratavam da modalidade powerlifting associada às respostas morfológicas e neuromusculares. Foram selecionados artigos nacionais e internacionais, retirados das bases de dados: Medline, SciELO, PUBMED, Ebsco e Portal Periódicos Capes entre 2000 a 2013. As palavras-chave utilizadas em português e inglês foram: powerlifting, powerlifting and training, weight training, powerlifting and anthropometrics. Livros texto básicos também foram inseridos para complemento das informações. Os principais achados demonstraram que as variáveis antropométricas (massa corporal, estatura, adiposidade) e disposição corporal (arquitetura) podem influenciar no desempenho do atleta. Assim como as magnitudes de força podem auxiliar no desempenho dos atletas de powerlifting, existe um equilíbrio entre volume e intensidade com o objetivo de desenvolvimento de força com baixas alterações morfológicas. Dessa forma, o presente estudo realizou uma breve revisão da modalidade que pode auxiliar atletas e técnicos no entendimento das melhorias neuromusculares e nas respostas morfológicas relacionadas à modalidade.(AU)

The aim of this study was to understand powerlifting sport associated with morphofunctional aspects involving modality. For this, were a literature review search articles dealing with the powerlifting sport associated morphological and neuromuscular responses was performed. National and international articles drawn from the databases were selected: Medline, SciELO, PubMed, Ebsco and Portal Periodicos Capes between 2000-2013. The keywords used in Portuguese and English were: powerlifting, powerlifting and training, weight training, powerlifting and anthropometrics. Basic textbooks were also inserted to supplement the information. The main findings showed that the anthropometric variables (weight, height, body fat) and body disposal (architecture) can influence the performance of the athlete. As the magnitudes of force can assist the performance of athletes in powerlifting, there is a balance between volume and intensity with the aim of developing strength with low morphological changes. Thus, this study conducted a brief review of the modality that can help athletes and coaches in understanding the neuromuscular improvements and morphological responses related to the modality.(AU)

Resistance Training After Myocardial Infarction in Rats: Its Role on Cardiac and Autonomic Function / Treinamento Resistido Após Infarto do Miocárdio em Ratos: Papel na Função Cardíaca e Autonômica

Background: Although resistance exercise training is part of cardiovascular rehabilitation programs, little is known about its role on the cardiac and autonomic function after myocardial infarction. Objective: To evaluate the effects of resistance exercise training, started early after myocardial infarction, on cardiac function, hemodynamic profile, and autonomic modulation in rats. Methods: Male Wistar rats were divided into four groups: sedentary control, trained control, sedentary infarcted and trained infarcted rats. Each group with n = 9 rats. The animals underwent maximum load test and echocardiography at the beginning and at the end of the resistance exercise training (in an adapted ladder, 40% to 60% of the maximum load test, 3 months, 5 days/week). At the end, hemodynamic, baroreflex sensitivity and autonomic modulation assessments were made. Results: The maximum load test increased in groups trained control (+32%) and trained infarcted (+46%) in relation to groups sedentary control and sedentary infarcted. Although no change occurred regarding the myocardial infarction size and systolic function, the E/A ratio (-23%), myocardial performance index (-39%) and systolic blood pressure (+6%) improved with resistance exercise training in group trained infarcted. Concomitantly, the training provided additional benefits in the high frequency bands of the pulse interval (+45%), as well as in the low frequency band of systolic blood pressure (-46%) in rats from group trained infarcted in relation to group sedentary infarcted. Conclusion: Resistance exercise training alone may be an important and safe tool in the management of patients after myocardial infarction, considering that it does not lead to significant changes in the ventricular function, reduces the global cardiac stress, and significantly improves the vascular and cardiac autonomic modulation in infarcted rats. .

Fundamento: Embora o treinamento físico resistido esteja inserido nos programas de reabilitação cardiovascular, pouco se sabe sobre seu papel isolado na função cardíaca e autonômica após o infarto do miocárdio. Objetivo: Avaliar os efeitos do treinamento físico resistido iniciado precocemente após o infarto do miocárdio na função cardíaca, no perfil hemodinâmico e na modulação autonômica de ratos. Métodos: Ratos Wistar machos foram divididos em Grupos Controle Sedentário, Controle Treinado, Infartado Sedentário e Infartado Treinado. Cada grupo foi composto por 9 ratos. Os animais realizaram o teste de carga máxima e a ecocardiografia ao início e ao final do treinamento físico resistido (em escada adaptada, 40 a 60% do teste de carga máxima, 3 meses, 5 dias/semana). Ao final, foram realizadas avaliações hemodinâmicas, de sensibilidade barorreflexa e da modulação autonômica. Resultados: O teste de carga máxima aumentou nos Grupos Controle Treinado (+32%) e Infartado Treinado (+46%) em relação aos Grupos Controle Sedentário e Infartado Sedentário. Embora a área de infarto do miocárdio e a função sistólica não tenham sido alteradas, a relação E/A (-23%), o índice de desempenho miocárdico (-39%) e a pressão arterial sistólica (+6%) foram melhorados pelo treinamento físico resistido no Grupo Infartado Treinado. Paralelamente, o treinamento induziu os grupos a benefícios adicionais nas bandas de alta frequência do intervalo de pulso (+45%), bem como a banda de baixa frequência da pressão arterial sistólica (-46%) nos ratos do Grupo Infartado Treinado em relação aos do Infartado Sedentário. Conclusão: O treinamento físico resistido dinâmico ...