title: Hemostatic responses to maximal exercise in oral contraceptive users.
abstract: OBJECTIVE
  This study examined the effect of exercise on markers of fibrinolysis and coagulation in users and nonusers of oral contraceptives.
  
  
  METHODS
  Fourteen oral contraceptive users and 14 nonusers performed a maximal exercise test on a cycle ergometer. Blood samples were collected before and immediately after the completion of the test. A repeated-measures analysis of variance was used for statistical analysis with values considered significant at P =.05.
  
  
  RESULTS
  Acute maximal exercise resulted in significant increases in tissue plasminogen activator activity in both groups. There was a trend toward a smaller increase in tissue plasminogen activator activity in oral contraceptive users, but the difference between groups was not statistically significant. Plasminogen activator inhibitor 1 activity was reduced with exercise in both groups but with a significantly greater decrease observed in the nonusers (P <.0001). Prothrombin fragment 1+2 was significantly higher (P <.0001) in the oral contraceptive group but did not change with exercise. Epinephrine levels before and after exercise were similar between the 2 groups, but postexercise norepinephrine concentrations were significantly lower (P =.026) in the oral contraceptive users.
  
  
  CONCLUSIONS
  These data suggest that oral contraceptive use blunts the fibrinolytic response to exercise. This, together with increased coagulation activation in oral contraceptive users, may alter the hemostatic balance during exercise.
authors.affiliation: Exercise Science Programs, The George Washington University Medical Center, Washington, DC, USA.
authors.forename: R
authors.initials: R
authors.lastname: Otterstetter
authors.forename: L M
authors.initials: LM
authors.lastname: Szymanski
authors.forename: G H
authors.initials: GH
authors.lastname: Kamimori
authors.forename: C M
authors.initials: CM
authors.lastname: Kessler
authors.forename: M R
authors.initials: MR
authors.lastname: Gold
authors.forename: B
authors.initials: B
authors.lastname: Fernhall
mesh_terms: D000328:Adult; D003276:Contraceptives, Oral / Q000009:adverse effects*; D004837:Epinephrine / Q000097:blood; D015444:Exercise / Q000502:physiology*; D005260:Female; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006487:Hemostasis; D006801:Humans; D009638:Norepinephrine / Q000097:blood; D010446:Peptide Fragments / Q000378:metabolism; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood; D011516:Prothrombin / Q000378:metabolism; D010959:Tissue Plasminogen Activator / Q000097:blood
chemical_list: D003276:Contraceptives, Oral; D006454:Hemoglobins; D010446:Peptide Fragments; D017395:Plasminogen Activator Inhibitor 1; C045879:prothrombin fragment 1.2; D011516:Prothrombin; D010959:Tissue Plasminogen Activator; D009638:Norepinephrine; D004837:Epinephrine