Effect of Exercise on Blood Coagulation
Whole blood clotting time was measured before and after four different intensities and durations of exercise, using 12 male college students as subjects. The exercises consisted of a 15-minute walk on a motor-driven treadmill at 2.5 m.p.h., a 2-hour walk on the treadmill at 2.5 m.p.h., a run to near exhaustion on the treadmill at 6.25 m.p.h., and a stepping exercise on a 12-inch bench, 30 steps per minute for 15 minutes. Thromboplastin generation rate was measured before and after the stepping exercise on blood samples drawn from 14 subjects, and thrombin generation rate was similarly measured on samples drawn from 16 subjects.
No statistically significant variation was found in whole blood clotting time of samples drawn before the exercise, 1 minute after the exercise, or 15 and 30 minutes after. Neither was there any significant change in the thromboplastin generation rate of samples drawn before, 1 minute after, and 30 minutes after exercise. Ten of the 16 subjects showed no change in thrombin generation rate after exercise. However, six subjects experienced an acceleration of thrombin generation from a mean time of maximum thrombin concentration at 5.2 minutes before exercise to 4.0 minutes one minute after exercise. This difference was statistically significant.
From these data it was concluded that, in general, exercise was not followed by hypercoagulability. However, in some subjects, thrombin generation rate was increased due to undetermined factors.
- Received October 10, 1961.
- © 1962 American Heart Association, Inc.