Fig. 1.
Hypothesized biological model relating physical activity to postmenopausal breast cancer risk. Strong epidemiologic evidence of an association with breast cancer risk (solid black arrows); limited epidemiologic evidence (irregular dashed arrows ); emerging epidemiologic evidence (short dashed arrows). Grey arrows relating biomarkers to each other are proposed in the literature; some of these relations are hypothesized, whereas others are well-established. Adapted from [11]