Summary
The effect of strenuous exercise on the fibrinolytic and coagulation mechanisms was
examined in six healthy male subjects. Five min bicycle exercise at a work-rate of
800 to 1200 kpm. min−1 produced an abrupt increase in plasma plasminogen activator levels which disappeared
after 90 min. However, there was no change in early or late fibrin degradation products
nor was there a change in fibrinopeptide A levels or βthromboglobulin levels after
exercise although activated partial thromboplastin times were significantly shortened.
It is concluded that strenuous exercise does not produce any real increase in fibrinogen-fibrin
conversion nor any real increase in the breakdown of these proteins. The role of exercise-induced
release of plasminogen activator remains unclear, but probably helps to maintain plasma
levels in a discontinuous manner concurrently with the continuous low-level secretion
from the vascular wall. The shortening of partial thromboplastin time may be due to
the raised levels of plasminogen activator changing the activation state of other
coagulation factors.
Keywords
Fibrinolysis - Plasminogen activator - Exercise - Fibrin degradation
