Aerobic Training in Metastatic Breast Cancer

Inclusion Criteria:

MSK histologically confirmed metastatic breast cancer
Measurable disease (or nonmeasurable bone-only disease) assessed by CT or PET/CT performed as part of standard of care, at the discretion of the attending oncologist in the Breast Medicine Service
≥18 years of age;
Life expectancy >3 months;
ECOG ≤ 1
Sedentary, as per the leisure score index (LSI) of the Godin Leisure-Time Exercise Questionnaire (GLTEQ) . Participants who perform regular moderate or vigorous intensity exercise at least 5 days/week, for at least 30 minutes/session, are not eligible

Able to achieve an acceptable peak baseline CPET, 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
Normal cardiac function (left ventricular ejection fraction ≥50%);
Medical clearance from attending oncologist indicating no relative contraindications to undergo a symptom-limited cardiopulmonary exercise test and aerobic training intervention;
Patients with "treated and stable" brain lesions of a duration of ≥ 2 months may be enrolled
Willing to be randomized to one of the study arms
Female

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
Room air desaturation at rest ≤ 85%
Respiratory failure
Acute non-cardiopulmonary disorders that may affect exercise performance or be aggravated by exercise (i.e., infection, renal failure, thyrotoxicosis)
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
Presence of extensive skeletal metastases, defined as more than five (5) sites of bony disease, or any symptomatic site of disease in the spine, hip, or femur. Note that, patients with more than five bony sites may be deemed eligible at the discretion of the attending oncologist.