Cardiac Rehabilitation Program on the Prevention of Cardiotoxicity in Breast Cancer Patients Undergoing Treatment With Anthracyclines and/or Trastuzumab

Inclusion Criteria: * Women aged between 18 and 70 years will be considered eligible. * Active residents of any municipality within Mexico City and the surrounding metropolitan area will qualify, conditioned that their maximum travel time from their residence to our recruitment center does not exceed three hours using private or public transportation. This criterion is established to ensure adherence to the protocol and availability for participation in the required interventions and assessments throughout the study. * Patients diagnosed with early-stage or locally advanced breast cancer (stages I, II, or III, according to the TNM classification-Tumor, Node, Metastasis) who will undergo treatment with anthracyclines and/or adjuvant/neoadjuvant anti-HER2 therapy will be included. Participants must be scheduled to receive pharmacological treatment, ensuring that the study focuses on a population undergoing specific therapies for breast cancer management. * Candidates must have the capacity, availability, and willingness to participate in an aerobic and resistance exercise program. Participants are required to possess both the physical ability and the willingness to actively engage in a structured exercise program, which includes aerobic and resistance activities essential to the study's objectives. * Patients will provide informed written consent to participate in the study. To uphold ethical research principles and ensure the protection of participants' rights, all patients must voluntarily give their informed consent after receiving comprehensive information regarding the study's objectives, procedures, benefits, and potential risks. Exclusion Criteria: * Metastatic disease: Individuals with medical or imaging evidence of metastasis to any peripheral organ. * Cardiovascular disease: Patients with a self-reported history of cardiovascular conditions, such as heart failure or uncontrolled hypertension, that may limit their ability to safely engage in physical activity. Additionally, those with peripheral arterial disease or valvular heart disease will not be eligible. * Ischemic heart disease: Patients with a history of ischemic heart disease. * Neurological disorders: Individuals with self-reported neurological diseases that significantly impair coordination, balance, or motor control, such as advanced Parkinson's disease, late-stage multiple sclerosis, or paralysis, making physical activity unsafe. * Musculoskeletal conditions: Patients with self-reported musculoskeletal injuries or disorders that hinder physical activity, including fractures within the last five years, moderate to severe sprains, tendinitis, or severe arthritis. * Uncontrolled systemic comorbidities: Individuals with decompensated systemic conditions, including heart failure, chronic kidney disease, or poorly controlled diabetes, will be excluded. * Severe respiratory diseases: Patients with severe respiratory conditions that prevent physical exercise participation. * Physical limitations: Individuals with mobility impairments or conditions requiring constant assistance for basic physical activities, such as those using assistive devices (e.g., wheelchairs, walkers) or with limb amputations, will not be eligible for participation. * Severe psychiatric disorders: Patients with uncontrolled psychiatric conditions, including schizophrenia, severe bipolar disorder, or major depressive disorder, that may interfere with their ability to actively participate in a supervised exercise program. Elimination Criteria: * Voluntary withdrawal from the protocol. * Development of severe cardiotoxicity requiring pharmacological treatment. * Adverse reactions to chemotherapeutic agents. * Disease progression according to the TNM classification during treatment. * Failure to complete at least 80% of the prescribed adjuvant or neoadjuvant oncological treatment. * Occurrence of adverse events during the study, such as falls or injuries. * Death during the study period. * Any accident related to the exercise protocol, including falls, sprains, or fractures.