In recent years, a growing number of studies have started to investigate the potential role of physical exercise as a coping intervention to improve quality of life in individuals undergoing chemotherapy following a breast cancer diagnosis. All these studies reported benefits of physical exercise on a wide spectrum of cancer treatment side effects and no studies reported any adverse events. All current studies have only focused on how exercise can help breast cancer patients cope with the side effects of chemotherapy, no study has examined whether exercise training during chemotherapy can improve the effectiveness of chemotherapy. Exercise is a potent intervention, which influences a number of the body's processes that may be particularly important for chemotherapy to be effective.

To effectively kill breast cancer cells, chemotherapy must be efficiently delivered to breast cancer cells in the bloodstream. Unfortunately, many breast cancers have a poorly developed blood supply that not only decreases the delivery of chemotherapy but also makes breast cancer cells more resistance to the beneficial effects of chemotherapy. In response, researchers have tried a number of different methods to help increase the delivery of chemotherapy to breast cancer cells without much success. However, endurance exercise training has been shown to improve the blood supply to a number of different tissues and organs in the body and therefore may also improve the delivery and effectiveness of chemotherapy in women diagnosed with cancer. Chemotherapy is a very powerful and beneficial treatment for breast cancer patients; therefore, investigating whether exercise training improves the effectiveness of this treatment is very important.

The aim of the proposed project is to investigate whether exercise training influences the effectiveness of chemotherapy in women diagnosed with breast cancer. If our hypotheses are correct, this information could help all breast cancer patients who are undergoing chemotherapy and other breast cancer treatments such as radiation therapy. Exercise is becoming recognized as a beneficial supportive intervention that may help patients cope with their treatments; thus, even if exercise does not improve the effectiveness of chemotherapy, it will still have additional beneficial effects on other physiologic and psychologic outcomes in breast cancer patients.

This research will address many currently unanswered questions regarding the effects of exercise on chemotherapy effectiveness in women diagnosed with breast cancer. This information will be crucially important to the establishment of new guidelines for breast cancer patients during chemotherapy and to exercise professionals who are designing and implementing exercise programs for breast cancer patients during and following chemotherapy treatment. Given the recent increased interest in the supportive role of exercise in breast cancer patients and recent guidelines published by the American Cancer Society, the potential clinical application of this research to breast cancer patients within North America could occur quite rapidly.