Two studies report that exercise and yoga can help maintain and in some cases improve quality of life in women with early-stage breast cancer. The first study found that resistance and aerobic exercise improved physical fitness, self-esteem and body composition, and that resistance exercise improved chemotherapy completion rates. The second study demonstrated that yoga was particularly beneficial for women who were not receiving chemotherapy during the study period. Both studies were published online in the Journal of Clinical Oncology (JCO).

In the first study, Canadian investigators explored the effects of exercise on quality of life, physical fitness and body composition in women receiving chemotherapy for early-stage breast cancer. This study, the Supervised Trial of Aerobic versus Resistance Training (START) trial, is the largest to date to explore the effects of exercise during chemotherapy and one of the first to evaluate a regimen of resistance exercise.

Researchers divided women into three groups: supervised resistance exercise three times weekly (82 women), supervised aerobic exercise three times weekly (78), and no aerobic or resistance exercise, also known as the "usual care" group (82). The median duration of chemotherapy and exercise was 17 weeks. Participants were surveyed at the beginning and middle of chemotherapy and up to four weeks after completing treatment.