This 3-month study will test whether a program to reduce sitting time, for breast cancer survivors experiencing some physical limitations, can improve their physical function and other important aspects of quality of life.

Many cancer survivors experience long-term physical problems following their cancer treatments and can often seem much older than same age peers who were never treated for cancer. This is known as accelerated aging. One way to improve accelerated aging is to increase moderate to vigorous intensity exercise; however, for many cancer survivors, especially those with physical limitations, increasing exercise levels is not possible. Another potential way to improve accelerated aging may be to decrease the amount of time spent sitting. Long periods of sitting are related to many physical and health problems. Cancer survivors spend more than 9 hours a day sitting and often increase the amount they sit after their cancer treatments. This study could help identify realistic intervention targets for many cancer survivors and be used to guide recommendations for improving physical function and quality of life after cancer.

Inclusion Criteria:

• Breast cancer survivors (stages I-IV) at least 1 year post active treatment (e.g., chemotherapy, radiotherapy)
• Breast cancer was treated with chemotherapy, radiation, immunotherapy, and/or endocrine therapy
• self-report difficulties with physical function
• self-report low levels of moderate to vigorous physical activity
• self-report high levels of sitting time

Exclusion Criteria:

• medical condition that interferes with ability to safely stand or stay balanced
• other cancer diagnoses that occurred after their breast cancer diagnosis
• Stage IV breast cancer with brain metastases or less than 12 months life-expectancy
• unable to commit to a 3-month study