SMAD2 and Myocardial fibrosis: One study indicated that four weeks of resistance exercise (8 sets/day, five times/week for 4 weeks) suppresses myocardial fibrosis following myocardial infarction via the upregulation of irisin expression, the activation of AMPK-Sirt1, and the inactivation of TGFβ1-Smad2/3 [109].