Fibrinopeptide A after strenuous physical exercise at high altitude.

To examine hemostasis after physical exercise at altitudes easily accessible to tourists by public transport, 20 young male volunteers were exposed to 3,457 m above sea level. Ten of them were subjected to an exhaustive exercise for about 8 min on a bicycle ergometer. The preexercise samples (n = 20) taken 1 h after arrival showed no significant alteration of coagulation compared with control values at 600 m. After the exercise the clotting times (P less than 0.001) and euglobulin lysis times (P less than 0.001) were shortened, whereas factor VIII activity (P less than 0.001) was elevated. There was, however, no significant difference in fibrinopeptide A levels between the exercise and the control group. Ethanol gelation test remained negative. We found no rise in fibrin(ogen) degradation products and fibrin(ogen) fragment E and thus conclude that there is no evidence for clinically relevant intravascular coagulation after short-term strenuous physical exercise at altitude.