title: Low endogenous thrombin potential in trained subjects.
abstract: BACKGROUND
  A paradox seems to exist: exercising leads to clotting activation in conventional clotting tests, but exercising persons have a low risk of thrombosis. In this study we tried to evaluate the effect of exercise performance status on in vitro plasma thrombin generation, which represents an overall function test of hemostasis.
  
  
  METHODS
  We compared 56 trained subjects to 98 healthy age matched sedentary volunteers. Blood samples were analyzed for thrombin generation using calibrated automated thrombography. Microparticles were quantified using ELISA. Additionally prothrombin fragments 1 + 2, thrombin-antithrombin complex, tissue factor pathway inhibitor, antithrombin and prothrombin were measured. The group of the trained subjects performed an incremental cycle-ergometer exercise test after taking the blood sample.
  
  
  RESULTS
  A significantly lower endogenous thrombin potential was observed in the group of the trained subjects compared to the sedentary individuals (p = 0.007). Microparticles (ELISA) were significantly lower in the trained subjects compared to the sedentary subjects (p = 0.001). Prothrombin fragments 1 + 2 (p < 0.001) and thrombin-antithrombin complex (p = 0.01) were significant higher in the trained subjects and antithrombin (p = 0.02) as well as prothrombin (p < 0.0001) were significantly lower in this group, whereas tissue factor pathway inhibitor values did not show significant differences. Both maximal and submaximal power output was significantly negatively related to endogenous thrombin potential (r = -0.43, r = -0.45) and thrombin peak (r = -0.44, r = -0.42).
  
  
  CONCLUSIONS
  Trained subjects have a lower endogenous thrombin potential than sedentary subjects possibly explaining the lower incidence of thrombosis in this group despite a higher acute clotting activation during strenuous exercise.
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Medical University of Graz, Austria.
authors.forename: Christina
authors.initials: C
authors.lastname: Cimenti
authors.forename: Axel
authors.initials: A
authors.lastname: Schlagenhauf
authors.forename: Bettina
authors.initials: B
authors.lastname: Leschnik
authors.forename: Manuel
authors.initials: M
authors.lastname: Schretter
authors.forename: Gerhard
authors.initials: G
authors.lastname: Tschakert
authors.forename: Werner
authors.initials: W
authors.lastname: Gröschl
authors.forename: Franz J
authors.initials: FJ
authors.lastname: Seibert
authors.forename: Peter
authors.initials: P
authors.lastname: Hofmann
authors.forename: Wolfgang E
authors.initials: WE
authors.lastname: Muntean
mesh_terms: D000293:Adolescent; D000328:Adult; D000990:Antithrombin III / Q000378:metabolism; D001777:Blood Coagulation; D055252:Cell-Derived Microparticles / Q000378:metabolism; D015444:Exercise; D005260:Female; D006487:Hemostasis; D006801:Humans; D008074:Lipoproteins / Q000378:metabolism; D008297:Male; D010447:Peptide Hydrolases / Q000378:metabolism; D012307:Risk Factors; D057185:Sedentary Behavior; D013917:Thrombin / Q000378:metabolism*; D013927:Thrombosis / Q000209:etiology / Q000378:metabolism; D055815:Young Adult
chemical_list: D008074:Lipoproteins; C046193:antithrombin III-protease complex; C051928:lipoprotein-associated coagulation inhibitor; D000990:Antithrombin III; D010447:Peptide Hydrolases; D013917:Thrombin