High- versus moderate-intensity aerobic exercise training effects on skeletal muscle of infarcted rats

Autor(es)

Moreira, Jose B. N. ^[1] ; Bechara, Luiz R. G. ^[1] ; Bozi, Luiz H. M. ^[1] ; Jannig, Paulo R. ^[1] ; Monteiro, Alex W. A. ^[1] ; Dourado, Paulo M. ^[2] ; Wisloff, Ulrik ^[3] ; Brum, Patricia C. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Phys Educ & Sport, BR-05508900 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Fac Med, Inst Heart, BR-05508900 Sao Paulo - Brazil

^[3] Norwegian Univ Sci & Technol NTNU, KG Jebsen Ctr Exercise Med, Trondheim - Norway

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Physiology; v. 114, n. 8, p. 1029-1041, APR 2013.
• Citações Web of Science: 46

Resumo

Moreira JB, Bechara LR, Bozi LH, Jannig PR, Monteiro AW, Dourado PM, Wisloff U, Brum PC. High- versus moderate-intensity aerobic exercise training effects on skeletal muscle of infarcted rats. J Appl Physiol 114: 1029-1041, 2013. First published February 21, 2013; doi:10.1152/japplphysiol.00760.2012.-Poor skeletal muscle performance was shown to strongly predict mortality and long-term prognosis in a variety of diseases, including heart failure (HF). Despite the known benefits of aerobic exercise training (AET) in improving the skeletal muscle phenotype in HF, the optimal exercise intensity to elicit maximal outcomes is still under debate. Therefore, the aim of the present study was to compare the effects of high-intensity AET with those of a moderate-intensity protocol on skeletal muscle of infarcted rats. Wistar rats underwent myocardial infarction (MI) or sham surgery. MI groups were submitted either to an untrained (MI-UNT); moderate-intensity (MI-CMT, 60% (V) over dot(O2) (max)); or matched volume, high-intensity AET (MI-HIT, intervals at 85% (V) over dot(O2) (max)) protocol. High-intensity AET (HIT) was superior to moderate-intensity AET (CMT) in improving aerobic capacity, assessed by treadmill running tests. Cardiac contractile function, measured by echocardiography, was equally improved by both AET protocols. CMT and HIT prevented the MI-induced decay of skeletal muscle citrate synthase and hexokinase maximal activities, and increased glycogen content, without significant differences between protocols. Similar improvements in skeletal muscle redox balance and deactivation of the ubiquitin-proteasome system were also observed after CMT and HIT. Such intracellular findings were accompanied by prevented skeletal muscle atrophy in both MI-CMT and MI-HIT groups, whereas no major differences were observed between protocols. Taken together, our data suggest that despite superior effects of HIT in improving functional capacity, skeletal muscle adaptations were remarkably similar among protocols, leading to the conclusion that skeletal myopathy in infarcted rats was equally prevented by either moderate-intensity or high-intensity AET. (AU)

• Processo FAPESP: 10/50048-1 - Bases celulares e funcionais do exercício físico na doença cardiovascular
• Beneficiário: Carlos Eduardo Negrão
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 09/12640-9 - Efeitos do treinamento físico intervalado de alta intensidade na musculatura esquelética de ratos com insuficiência cardíaca
• Beneficiário: Jose Bianco Nascimento Moreira
• Modalidade de apoio: Bolsas no Brasil - Mestrado