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:

1. Achieving a plateau in oxygen consumption, concurrent with an increase in power
output;

2. A respiratory exchange ratio ≥ 1.10;

3. Attainment of maximal predicted heart rate (HRmax) (i.e., within 10 bpm of
age-predicted HRmax [HRmax = 220-Age[years]);

4. 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:

1. Acute myocardial infarction within 3-5 days of any planned study procedures

2. Unstable angina

3. Uncontrolled arrhythmia causing symptoms or hemodynamic compromise;

4. Recurrent syncope

5. Active endocarditis;

6. Acute myocarditis or pericarditis

7. Symptomatic severe aortic stenosis

8. Uncontrolled heart failure

9. Acute pulmonary embolus or pulmonary infarction within 3 months of any planned
study procedures

10. Thrombosis of lower extremities

11. Suspected dissecting aneurysm

12. Uncontrolled asthma

13. Pulmonary edema

14. Room air desaturation at rest ≤ 85%

15. Respiratory failure

16. Acute non-cardiopulmonary disorders that may affect exercise performance or be
aggravated by exercise (i.e., infection, renal failure, thyrotoxicosis)

17. 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.