Introduction: Doxorubicin (DOX) is one of the most effective antitumor drugs for breast cancer treatment. DOX is associated to high toxicity in multiple organs and tissues. This study aimed to assess the effects of resistance exercise training (RET) in the hematological parameters of rats with mammary cancer treated with DOX. Material & Methods: Wistar Rats were divided into six groups: I (sedentary, SED), II (...