Physical exercise activates blood coagulation and enhances fibrinolytic activity.
To investigate whether these actiivations of blood coagulation and fibrinolysis are
balanced post-exercise and during the period of recovery, 11 moderately active young
men were examined immediately after a standardised cycle ergometer test and during
the 24 h period of recovery. Blood samples were obtained at rest, immediately after
exerciise, and 2, 6 and 24 h after exercise. All post-exercise values were corrected
for any change in plasma volume. Exercise induced a significant increase in factor
VIII activity and this occurred! with a significant shortening of activated partial
thromboplastiin time. A concomitant enhancement of tissue plasminogen activity resulted
in significant increases in tissue plasminogen activity antigen and total fibrin/fibrinogen
degradation products, and a sigmificant decrease in tissue plasminogen activator inhiibitor-1
activity. Increases in coagulation and fibrinolytic activity changed in parallel during
exercise. However, during recovery, while the increase in factor VIII activity post-exercise
persisted 2 and 6h into recovery, fibrinolytic activity demonstirated a sharp fall.
It is concluded that whereas the enhanced fibrinolytic activity during exercise appears
to counterbalance the increase in blood coagulability, this haemostatic balance is
not maintained during recovery. This perturbed blood haemostasis could constitute
an enhanced risk for coronary artery thirombo-sis and may contribute to exercise-related
cardiowascular events.
Key words
Exercise - blood coagulation - fibrinolysis - Ihaemo-static balance - thrombosis
