Increased platelet aggregability and prostacyclin biosynthesis induced by intense physical exercise

Abstract Changes in platelet aggregability during maximal bicycle ergometry were studied in healthy untrained subjects. Ex vivo platelet aggregation in response to ADP and collagen was measured in whole blood by impedance aggregometry or by direct electronic counting in an Ultra-Flo 100 platelet counter. This last method revealed that the platelet aggregation induced by low concentration of ADP (0.5–1.0 μM) was significantly enhanced during exercise. The plasma level of beta-thromboglobulin and the urinary excretion of 2, 3-dinor-6-keto prostaglandin F1 alpha were also increased. These data indicate that an intense physical exercise enhances the aggregability of human platelets and induces a compensatory increase in prostacyclin biosynthesis.