Inclusion Criteria

- INCLUSION CRITERIA:

This study will enroll 40 breast cancer survivors and 40 women at high risk for breast
cancer. All participants must fulfill the following criteria:

Age 18 to 75.

Sedentary at baseline, as defined by a weekly leisure-time activity score of 15 or less on
the Godin Leisure-Time Exercise Questionnaire. This cutoff is equivalent to engaging in
moderate activity less than 3 times a week.

Ability to complete all study questionnaires, or a willing friend or family member who
will assist in questionnaire completion.

ECOG performance status 0-1.

Ability to successfully perform the level of physical activity prescribed by the protocol,
as assessed by the Physical Activity Readiness Questionnaire (PAR-Q).

Any participant who answers yes to any of the questions in this screening tool will
undergo medical evaluation at the Clinical Center, as appropriate, prior to enrolling on
the study.

Cardiac risk will be assessed after a complete history and physical exam, and will be
determined by the examining physician. Only patients who are felt to be increased cardiac
risk will have an EKG performed. This will include patients who answer yes to any of the
questions on the PAR-Q that assess cardiac risk (#1,2,3,4,6). Patients with worrisome EKG
findings or findings in the history or physical exam that warrant further work-up in the
opinion of the health care provider will be referred to the cardiology consult service, or
if non-urgent, will be referred back to their source of regular medical care for clearance
prior to enrolling on the study.

If history of cancer (other than invasive breast cancer, squamous or basal cell skin
cancers), subject must have no evidence of disease at time of enrollment AND no history of
cancer directed treatment in the 2 years preceding enrollment.

Breast cancer survivors:

Eligible breast cancer survivors will be women with a documented history of Stage I, II or
III invasive breast cancer who are at least two months from the completion of their
primary therapy, including surgery, radiation and chemotherapy. Current use of hormonal
therapy such as tamoxifen or aromatase inhibitors, will be permitted, however subjects
must have completed 2 months of hormonal therapy prior to beginning the study in order to
achieve steady state.

Women at high risk for breast cancer:

Women will be considered at high risk for developing breast cancer if they fulfill one of
the following criteria:

A Gail model risk of greater than or equal to1.7 percent over 5 years from study entry or
a Claus model lifetime risk of greater than 20 percent.

Lobular neoplasia.

Atypical ductal hyperplasia.

Ductal carcinoma in situ (DCIS) that has been previously treated. Patients must be at
least 2 months from completion of primary therapy, and if treated with hormonal therapy,
they must have completed at least two months of hormonal therapy.

Deleterious mutations in BRCA-1 or 2 OR A priori risk assessment of 20 percent chance or
greater of carrying a BRCA1/2 gene mutation. The BRCAPRO model (109) will be used to
assess this risk.

EXCLUSION CRITERIA:

Currently pregnant or planning to become pregnant during the study period. Pregnancy will
be assessed in women of childbearing potential prior to enrolling in stage II of the
study. Postmenopausal women and women who have had a previous hysterectomy, oophorectomy
or tubal ligation will not be required to undergo a pregnancy test.

Uncontrolled intercurrent illness, including, but not limited to: ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
arrhythmia, recent myocardial infarction or stroke, or psychiatric illness/social
situations that would limit compliance with study requirements.

Physical conditions that preclude the amount of daily walking prescribed by the protocol
(e.g., severe arthritis, use of a walker or cane, wheelchair-bound, etc.).

Medical or psychiatric disorder which would, in the opinion of the Principal Investigator,
render the subject unable to provide informed consent.

Patients with metastatic or recurrent disease will be excluded because of difficulty
interpreting results in the context of women with a disease burden and/or on chemotherapy.