The effects of prolonged exercise for 60 min on blood clotting and fibrinolytic systems

The authors have found an increase of anti-activator during recovery from maximum exercise, and prolongation of euglobuline lysis time due to prolonged exercise was observed by some investigators on the next morning of the day of prolonged exercise. Therefore, the present study was conducted to evaluate the effects of prolonged exercise on blood clotting and fibrinolytic systems during recovery for 22 hours in vitro. The results: 1) aPTT immediately after exercise was shorter than pre-exercise level in every subject, viz. changed from 28.2 sec to 26.2 sec on the average. Thereafter, it returned to the pre-exercise level within 2 to 4 hours after the end of exercise, and no changes were observed during the rest of recovery period. 2) F VIII, showed almost similar change to aPTT: the mean F VIII increased from 109.3% before exercise to 161.0% immediately after exercise, but its increasing rate varied from 16 to 81% among subjects. Although, 2 out of the 4 subjects showed decrease and returned to the pre-exercise level in 4 hours after exercise. There was a highly significant (r = 0.9171, P < 0.001) relationship between aPTT and F VIII activity.