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Introduction

It has been shown that intense physical activity is associated with acute coronary thrombosis and arterial occlusion in sedentary, unfit individuals or in those with preexisting vascular disease . In both cases, exercise results in disruption of coagulation and the fibrinolytic systems that up-regulate platelet activity. A recent systematic review of the association between acute exercise and hemostasis suggests that the risk of thrombosis is increased shortly after the exercise ends . However, the paradox between the ability of exercise to prevent or to stimulate coronary thrombosis is controversial and depends on exercise intensity, baseline fitness level, acute vs. chronic exercise, and others factors . In sedentary individuals, platelet aggregation [induced by adenosine diphosphate (ADP) stimulation] was increased post-maximal exercise and was significantly reduced following moderate types of exercise . Furthermore, reduced shear-induced platelet aggregation was reported in subjects participating in regular physical activity compared with their sedentary counterparts. This effect was reversed after deconditioning . Furthermore, higher platelet reactivity was demonstrated in cardiac and chronic heart failure patients undergoing an exercise stress test with reduced platelet aggregation . Aspirin therapy seems to have no impact on platelet aggregability following exercise among aspirin responders but is associated with increased platelet reactivity among nonresponders . In contrast with the conflicting reports among cardiac patients, there is consensus among patients with metabolic syndrome and diabetics who exhibit metabolic alterations, increased oxidative stress, and inflammation, all of which contribute to increased thromboxaneA ₂ synthesis and platelet activation under resting conditions . An increased prothrombotic state, which is associated with higher platelet reactivity among diabetic patients, makes those patients prone to increased risk of acute myocardial infarction and sudden death . However, little is known about platelet function in diabetic patients following acute exercise. Therefore, the purpose of the present study was to assess platelet reactivity in type 2 diabetic patients subjected to acute exercise stress test.