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The study, published in the British Journal of Sports Medicine, examined 130,957 women of European descent, of which 69,838 had tumors that had spread locally, and 6,667 had tumors that had not yet spread. The control group included 54,452 women who did not develop breast cancer. The researchers also relied on studies that examined genetic predisposition to physical activity or sitting time, measured by a bracelet worn on the wrist, to examine how physically active the study participants were. The researchers then assessed the risk of breast cancer in relation to menopause, type of cancer, stage (size and extent of tumor spread) and grade.