Balanced Intense Exercise Training Induces Atrial Oxidative Stress Counterbalanced by the Antioxidant System and Atrial Hypertrophy That Is Not Associated with Pathological Remodeling or Arrhythmogenicity

Although regular exercise training is associated with cardiovascular benefits, the increased risk of atrial arrhythmias has been observed after vigorous and related to oxidative stress. We aimed at investigating exercise-induced remodeling in a rat model an athlete’s heart determining sex-specific differences. Age-matched young adult rats were divided into female exercised, control, male control groups. After exercised animals completed 12-week-long swim protocol, echocardiography vivo cardiac electrophysiologic investigation performed. Additionally, histological gene expression analyses carried out. Post-mortem weight data examination confirmed marked hypertrophy. found antioxidant enzymes along nitro-oxidative No alteration was regarding markers pathological remodeling, apoptotic, proinflammatoric, profibrotic processes. Exercise prolonged right effective refractory period. could not induce by programmed stimulation any decreased potassium channels. Female gender lower collagen density. Long-term, balanced training-induced hypertrophy harmful electrical no inflammatory or response atrium rats.