Exercise Therapy to Improve Cardiovascular Health in Post-Menopausal Women After Treatment for Early Stage Breast Cancer

Inclusion Criteria:

* Aged 21-80 years
* Female
* Surgically resected early stage (I-III) primary breast cancer
* Post-menopausal, defined as one of the following:

  * Age ≥ 45 with no menses for at least 2 years
  * Chemically and/or surgically induced menopause through ovarian suppression, as determined by the primary oncologist
  * Estradiol level of ≤30 pg/mL
* An interval of at least one year, but no more than five years, following the full completion of definitive therapy for malignant disease. Definitive therapy is defined as:

  * Surgery plus radiation
  * Surgery plus chemotherapy
  * Surgery plus trastuzumab
* Exercise intolerance (i.e., patients must have a VO2peak below the predicted for active age and sex-matched individuals. (+/- the technical error of 1.32 mL/kg/min)\].

Note: Normative values are available up to 80 years of age)

* Able to complete an acceptable baseline CPET, in the absence of high-risk ECG findings or other inappropriate response to exercise as determined by the PI, as defined by any of the following criteria:

  * Achieving a plateau in oxygen consumption, concurrent with an increase in power output;
  * A respiratory exchange ratio ≥ 1.10;
  * Attainment of maximal predicted heart rate (HRmax) (i.e., within 10 bpm of age-predicted HRmax \[HRmax = 220-Age\[years\]);
  * Volitional exhaustion, as measured by a rating of perceived exertion (RPE) ≥ 18 on the BORG scale
* Willingness to comply with all study-related procedures.

Exclusion Criteria:

* Any of the following absolute contraindications to cardiopulmonary exercise testing:

  * Acute myocardial infarction within 3-5 days of any planned study procedures
  * Unstable angina
  * Uncontrolled arrhythmia causing symptoms or hemodynamic compromise
  * Recurrent syncope
  * Active endocarditis
  * Acute myocarditis or pericarditis
  * Symptomatic severe aortic stenosis
  * Uncontrolled heart failure
  * Acute pulmonary embolus or pulmonary infarction within 3 months of any planned study procedures
  * Thrombosis of lower extremities
  * Suspected dissecting aneurysm
  * Uncontrolled asthma
  * Pulmonary edema
  * Respiratory failure
  * Acute non-cardiopulmonary disorders that may affect exercise performance or be aggravated by exercise (e.g., infection, renal failure, thyrotoxicosis)
* Presence of any other concurrent, actively treated malignancy
* History of any other malignancy treated within the past 3 years (other than non-melanoma skin cancer)
* Presence of distant metastatic disease (i.e., stage IV)
* Room air desaturation at rest ≤ 85%
* Mental impairment leading to inability to cooperate.
* Any other condition or intercurrent illness that, in the opinion of the investigator, makes the participant a poor candidate for the trial.