In a September 2008 article, A Prospective Study of Cardiorespiratory Fitness and Breast Cancer Mortalityresearchers at University of South Carolina and University of North Texas wrote that: “We examined the association between cardiorespiratory fitness (CRF) and risk of death from breast cancer. Women (N = 14,811), aged 20 to 83 yr with no prior breast cancer history, received a preventive medical examination at the Cooper Clinic in Dallas, Texas, between 1970 and 2001. Mortality surveillance was completed through December 31, 2003.” Their findings: In this study, we observed an inverse association between CRF and the risk of breast cancer mortality. Women in the moderate and high CRF groups demonstrated a 33% and 55% lower risk, respectively, of dying of breast cancer. This association persisted after adjustment of other available potential confounders. Women with an exercise capacity less than 8 METs (fitness level) had a nearly threefold higher risk of dying of breast cancer compared with those with higher METs level (Q8). These data suggest that an exercise capacity of at least 8 METs may be needed to provide substantially protective benefits.”