Physical activity and breast cancer: Testing a theoretical model

Breast cancer is an increasing health concern for women in the United States. The present study analyzed physical activity as a predictor of breast cancer. A theoretical model provided the framework for the individual and multifactorial analyses of physical activity and breast cancer risk factors on breast cancer prediction. A subset of the Aerobics Center Longitudinal Study (ACLS) provided the study sample of 4,520 women, with 150 incident cases of breast cancer.

Women with breast cancer were on the average 5 years older and slightly less fit than women without breast cancer. Women with breast cancer reported a later menopause, earlier menarche, more miscarriages, and later age to first use birth control pills and hormone replacement therapy.

Results of logistic regression analysis found aerobic type of exercise and frequency of jogging to be significant predictors of breast cancer. Women with breast cancer were more likely at initial entry in the ACLS to not participate in jogging as a physical activity, be older, have a higher resting pulse, and report a history of other cancer. Hormonal events when combined with age, were not predictive of breast cancer.