The benefits of endurance training in cardiomyocyte function in hypertensive rats are reversed within four weeks of detraining

► We studied the effects of training/detraining on the cardiomyocyte function of SHR. ► Hypertension resulted in deficient cardiomyocyte contractile function. ► Exercise improved cardiomyocyte [Ca2 +]i transient and contractile function in SHR. ► These benefits were related to increased PLBser16 and SERCA2a cardiac expression. ► Such exercise training-induced adaptations were reversed within 4 weeks of detraining.