Platelet function and fibrinolytic activity following distance running

Area of Science:

• Exercise Physiology
• Hematology
• Sports Medicine

Background:

• Strenuous exercise can impact blood coagulation and platelet function.
• The effects of long-term endurance running on these systems are less understood.
• Previous research suggests short-term intense exercise may induce platelet hyperaggregation.

Purpose of the Study:

• To investigate the effects of long-distance running on platelet function and fibrinolytic activity.
• To compare the responses between elite marathon runners and non-runners.
• To differentiate the impact of endurance running versus short-term strenuous exercise.

Main Methods:

• 6 elite marathon runners and 6 non-runners completed standardized test runs (28 km and 12 km, respectively).
• Blood samples were analyzed for platelet aggregability, serotonin release, platelet factor 4, antithrombin III levels, and euglobulin lysis time.
• Measurements were taken immediately following exercise.

Main Results:

• Both groups exhibited similar responses in platelet function.
• A significant decrease in adenosine diphosphate (ADP)-induced platelet aggregability and serotonin release was observed.
• Platelet factor 4 increased, antithrombin III remained constant, and euglobulin lysis time shortened by ~50%, indicating increased fibrinolytic activity.

Conclusions:

• Long-term distance running leads to an exhaustion of platelet aggregation capacity.
• Endurance running equally enhances fibrinolytic activity in both trained and untrained individuals.
• This contrasts with short-term, strenuous exercise, which is known to induce platelet hyperaggregation.