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Fitness, Exercise, and Coronary Calcification


¬oth higher coronary artery calcification (CAC) scores and reduced cardiorespiratory fitness (CRF) are independently strong predictors of future cardiovascular events. CAC is a direct measure of coronary atherosclerosis, the cause of most cardiovascular events. CRF, often measured by exercise treadmill time, is an estimate of maximal oxygen uptake and a surrogate measure of cardiac stroke volume. Rearranging the Fick equation demonstrates that maximal oxygen uptake is the product of cardiac output (heart rate ◊ stroke volume) and the arterial-venous O2 difference. Because heart rate is largely age-determined and the arterial-venous O2 difference varies little among healthy individuals, maximal oxygen uptake, and therefore CRF, are proxies for stroke volume and cardiac performance.

Circulation. 2018;137(18):1896-1898.