ObjectiveTo investigate the efficiency of short-term inspiratory muscle training program associated with combined aerobic and resistance exercise on respiratory muscle strength, functional capacity and quality of life in patients who underwent coronary artery bypass and are in the phase II cardiac rehabilitation program.MethodsA prospective, quasi-experimental study with 24 patients who underwent coronary artery bypass and were randomly assigned to two groups in the Phase II cardiac rehabilitation program: inspiratory muscle training program associated with combined training (aerobic and resistance) group (GCR + IMT, n=12) and combined training with respiratory exercises group (GCR, n=12), over a period of 12 weeks, with two sessions per week. Before and after intervention, the following measurements were obtained: maximal inspiratory and expiratory pressures (PImax and PEmax), peak oxygen consumption (peak VO2) and quality of life scores. Data were compared between pre- and post-intervention at baseline and the variation between the pre- and post-phase II cardiac rehabilitation program using the Student's t-test, except the categorical variables, which were compared using the Chi-square test. Values of P<0.05 were considered statistically significant.ResultsCompared to GCR, the GCR + IMT group showed larger increments in PImax (P<0.001), PEmax (P<0.001), peak VO2 (P<0.001) and quality of life scores (P<0.001).ConclusionThe present study demonstrated that the addition of inspiratory muscle training, even when applied for a short period, may potentiate the effects of combined aerobic and resistance training, becoming a simple and inexpensive strategy for patients who underwent coronary artery bypass and are in phase II cardiac rehabilitation.

Exercise training has demonstrated cardioprotection effects. However, the exact mechanism behind this effect is not is clear. The present study evaluated the effects of 12 weeks of previous treadmill training on the levels of oxidative damage, antioxidant enzyme activity and injury in the myocardium of rats submitted to infarction induced by isoproterenol (ISO). Isoproterenol treatment (80 mg/kg given over 2 days in two equal doses) caused arrhythmias and 60% mortality within 24 h of the last injection in the control group (C + ISO) group when compared with the saline control group (saline). Creatine Kinase--MB levels were markedly increased in hearts from ISO-treated animals in the C + ISO group. Twelve weeks of treadmill training reduced superoxide production, lipid peroxidation levels and protein carbonylation in these animals, as well as increasing the activities and expressions of SOD and CAT. Previous training also reduced CK-MB levels and numbers of deaths by 40%, preventing the deleterious effects of ISO. Based on the data obtained in this study, it is suggested that 12-week treadmill training increases antioxidant enzymes, decreases oxidative damage and reduces the degree of infarction induced by ISO in the hearts of male rats.

Our results indicate that ROS induced by acute exercise play the important role of activating eNOS, a process apparently mediated by Akt and AMPK.

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Respostas cardiorrespiratórias durante dois testes de exercício submáximos em participantes de um programa de reabilitação cardíaca: resultados preliminares RESUMO Introdução-A capacidade submáxima de exercício avalia a capacidade funcional do indivíduo, podendo ser mensurada pelo Teste de Caminhada de Seis Minutos (TC6m) e pelo Teste do Degrau de Quatro Minutos (TD4). Objetivo-Comparar as respostas cardiorrespiratórias e percepção de esforço entre o TC6m e o TD4 em pacientes submetidos à cirurgia de revascularização do miocárdio (CRM) participantes de um programa de reabilitação cardíaca. Metodologia-Estudo transversal composto por sete homens (58,71 ± 9,37 anos). Foram analisadas as respostas cardiorrespiratórias (saturação periférica de oxigênio-SpO2; frequência cardíaca-FC; pressão arterial sistólica-PAS; pressão arterial diastólica-PAD), sensação de dispneia (SD) e sensação de fadiga de membros inferiores (SFMMII) por meio da Escala de Borg modificada. Os testes seguiram as diretrizes da American Thoracic Society (ATS 2002),). Resultados-Constatou-se diferença significativa (p<0,05) nos deltas da PAS e PAD entre os testes. Conclusão-Nossos resultados sugerem que tanto o TC6m quanto o TD4 estimam a capacidade submáxima de exercício, porém o TD4 exige uma maior demanda metabólica, observada por maior incremento da pressão arterial.