Abstract
Despite recommendations for cancer survivors to engage in either moderate or vigorous physical activity, cancer survivors report enjoying light intensity physical activity, and have greater intentions to engage in light intensity physical activity. Furthermore, light intensity physical activity may be beneficial for mental health. Many cancer survivors reduce their levels of physical activity during their treatment for cancer and light intensity physical activity may be appropriate to resume physical activity participation post-treatment. The purpose of this study was to examine the extent to which light, moderate, and vigorous physical activity predict depressive symptoms (an index of mental health) in breast cancer survivors over 1-year post treatment. Participants (N = 201) were a sample of breast cancer survivors who completed self-report questionnaires and wore an accelerometer for 7 consecutive days (to measure physical activity), on five occasions over 1-year post-treatment. After controlling for age, marital status, breast cancer stage, fruit and vegetable consumption, income, and highest level of education, hierarchical linear modeling showed that light (b=-1.24, p=0.02) and moderate (b=-2.05, p=0.00) intensity physical activity, but not vigorous (b=-0.55, p=0.33) intensity physical activity, predicted depressive symptoms over time. The findings may have implications for physical activity guidelines for cancer survivors as light physical activity may play a role in mitigating depressive symptoms following treatment for breast cancer.Acknowledgments: Canadian Institutes of Health Research