Introduction: The present case study is an analysis of the effect of compression socks on hemostatic activation following a marathon in a female endurance athlete found to be heterozygous for the coagulation factor V (F5 1691 G>A [Arg>Gln rs6025/560]) risk allele that predisposes one to a genetically inherited disorder of blood clotting, Factor V Leiden.
Methods: Markers for coagulation and fibrinolysis were obtained 24 h prior to (PRE), immediately after (FINISH) and 24 h after (POST) completion of two marathons: the first in which the runner was not wearing compression socks, and the second in which the runner wore compression socks throughout the race.
Results: Compression socks worn during a marathon appeared to lower the overall impact on hemostasis as well as clot formation in this particular athlete as evidenced by lower t-PA (-56%), TAT (-63%) and D-dimer (-30%).
Conclusions: Hemostatic activation may be lower with the use of compression socks, and thus may be effective for preserving hemostasis in endurance athletes at risk.
Keywords: Factor V Leiden; Marathon; compression socks; hemostasis.