The purpose of the study is to compare the effects of one exercise/counseling protocol with usual care on long term exercise adherence and on changes in health related outcomes after breast cancer diagnosis.

Physical activity may improve quality of life, the control of comorbid conditions, and weight management while reducing breast cancer recurrence and mortality among breast cancer survivors. Unfortunately, most breast cancer survivors do not engage in regular physical activity. In fact, breast cancer survivors are often less active after a diagnosis and may not return to pre-diagnosis activity levels. Therefore, we conducted a pilot study, "BEAT Cancer", to test a specifically defined physical activity behavior change intervention to increase physical activity for breast cancer survivors. The pilot study showed significant improvement in both physical activity and health outcomes for the study participants after the intervention. Importantly, the pilot intervention resulted in changes in physical activity and social cognitive theory constructs, such as the participants feeling more confident in their ability to exercise. The positive results enhance our potential for testing mechanisms that encourage physical activity behavior change in breast cancer survivors. The current study is a follow-up to confirm program effectiveness at 3 months and to test sustainability of results at 3-12 months. We propose a multi-center, randomized controlled trial enrolling 356 breast cancer survivors with the following study aims:

1. To compare the effects of the 3-month BEAT Cancer physical activity behavior change intervention to usual care on short and longer term physical activity adherence among breast cancer survivors. We hypothesize that, compared with usual care, the intervention will result in a significant increase in physical activity after the intervention that will be maintained up to 12 months after baseline.
2. To better understand the reasons why breast cancer patients change their physical activity behavior, we will compare the effects of the BEAT Cancer physical activity behavior change intervention to usual care on social cognitive factors to see if such changes contribute to physical activity behavior change. We hypothesize that, compared with usual care, the intervention will result in significant improvements in social cognitive factors which lead to changes in physical activity behavior.
3. We also aim to compare the short and longer term health effects of the BEAT Cancer physical activity behavior change intervention when compared with usual care. We hypothesize that, compared with usual care, the intervention will result in significant improvements in fitness, muscle strength, waist-to-hip ratio, quality of life, fatigue, and sleep quality, while reducing joint dysfunction.

Inclusion Criteria:

• Female breast cancer patients between the ages of 18 and 70 years of age with a diagnosis of ductal carcinoma in situ (DCIS) or Stage I, II, or IIIA breast cancer and who are not currently receiving (and do not plan to receive during the duration of the study) chemotherapy or radiation therapy. The participant may be taking longer term therapies such as aromatase inhibitors, estrogen receptor modulators, etc. The upper age limit of 70 years was chosen to reduce the likelihood of adverse events or study drop-out due to increasing comorbidities (e.g., cardiovascular disease) that occur with age.
• If the patient has undergone a surgical procedure, enrollment will be delayed until ≥ 8 weeks post-procedure.
• English speaking.
• Medical clearance for participation provided by primary care physician or oncologist.
• Participating, on average, in no more than 60 minutes of moderate physical activity or no more than 30 minutes of vigorous activity per week during the past six months.

Exclusion Criteria:

• Diagnosis of dementia or organic brain syndrome.
• Medical, psychological, or social characteristic that would interfere with ability to fully participate in program activities and assessments (e.g., psychosis, schizophrenia, etc.).
• Contraindication to participation in a regular physical activity program.
• Metastatic or recurrent disease.
• Inability to ambulate.
• Anticipates undergoing elective surgery during the duration of the intervention which would interfere with intervention participation (e.g., breast reconstructive surgery).
• Planned travel that would interfere with scheduled study sessions (no travel in the 1st 4 months and no travel ≥ 1 week in the last 8 weeks of the intervention).