Furthermore, a treadmill running program (25–40 min at 14–20 m/min, 5 days/week, 8–14 weeks), starting either before or after injecting estrogen-dependent MC4L2 cancer cells in female mice, reduces breast tumour volume and the levels of IL-6 in the tumour, on condition that the mice continue exercising after the onset of tumorigenesis [93]. Here, IL6 is linked to cancer.