Exercise and thrombosis

Long-term moderate or strenuous physical activity is associated with a cons iderable reduction in cardiovascular morbidity and mortality. This article reviews the evidence to suggest that part of the effect is mediated through the effects on thrombogenic factors. Fibrinogen has been convincingly show n to be an independent cardiovascular risk factor. Other hemostatic and fib rinolytic parameters that are predictive of coronary events include factor VII, platelet hyperreactivity, plasminogen activator inhibitor-1, and tissu e-plasminogen activator. The effects of exercise on fibrinogen have been st udied intensively One randomized, controlled trial, two other intervention studies and a large number of population-based cross-sectional studies have consistently found an inverse relationship between various measures of spo rt activity or leisure activity and plasma levels of fibrinogen. The magnit ude of the effect might be associated with a sizeable reduction in major co ronary events. Relatively few data are available on endurance exercise and markers of the fibrinolytic system. Acute exercise leads to a transient act ivation of the coagulation system, which is accompanied by an increase in t he fibrinolytic capacity in healthy subjects. However, patients with ischem ic heart disease, who cannot increase their fibrinolytic potential, may be at considerable risk for acute ischemic events if they are exposed to unacc ustomed strenuous physical exertion. It is concluded that physical activity has profound effects on thrombogenic factors and that these mechanisms cou ld contribute to its beneficial cardiovascular effects. Coronary Artery Dis 1 1:123-127 (C) 2000 Lippincott Williams & Wilkins.