Background: Both exercise and cold exposure increase blood coagulation potential but their combined effects are not known. The purpose of the present study was to assess blood coagulation factors in response to submaximal exercise in the cold environment among patients with stable coronary artery disease (CAD).
Methods: Sixteen men (61.1 ± 7.1 years) with stable CAD participated in three 30-min experimental conditions (seated rest in - 15 °C and exercise in both + 22 °C and - 15 °C) in random order. The employed exercise consisted of brisk walking (66-69% of maximal heart rate). Factor VII (FVII), fibrinogen, D-dimer and von Willebrand factor (vWF) were analyzed from blood samples obtained before, immediately and one hour after each experiment.
Results: On average, FVII activity (95% confidence interval, CI) was 123 (108-143) %, 123 (106-140) %, 121 (103-139) % (baseline, recovery 1, recovery 2), fibrinogen concentration (95% CI) 3.81 (3.49-4.12) g/l, 3.71 (3.34-4.08) g/l, 3.65 (3.26-4.05) g/l, D-dimer concentration (95% CI) 0.42 (0.28-0.56) µg/ml, 0.42 (0.29-.55) µg/ml and 0.39 (0.29-0.49) µg/ml, and vWF activity (95% CI) 184 (135-232) %, 170 (128-212) % and 173 (129-217) % after exercise in the cold. Average FVII activity varied from 122 to 123%, fibrinogen concentration from 3.71 to 3.75 g/l, D-dimer concentration from 0.35 to 0.51 µg/ml and von Willebrand factor activity from 168 to 175% immediately after each three experimental condition.
Conclusions: Our findings suggest that submaximal lower body exercise carried out in a cold environment does not significantly affect blood coagulation parameters among patients with stable CAD.
Keywords: Coagulation; Cold; Coronary artery disease; Exercise.