title: Age-related effects of regular physical activity on hemostatic factors in men.
abstract: BACKGROUND
  Age-related changes in blood coagulation and fibrinolytic factors are associated with an increase in risk of thrombotic events. The purpose of this study was to assess the effects of age, regular aerobic exercise and detraining on blood coagulation and fibrinolytic factors in men.
  
  
  METHODS
  Initially, 41 sedentary and 42 physically active men (20-64 years) were analyzed for plasma levels of coagulation and fibrinolytic factors. Twelve sedentary men were then subjected to 16-week aerobic exercise training and subsequent 2-week detraining. Their blood samples taken at rest were assayed for activity levels of prothrombin, coagulation factor (F) V, VII, VIII, IX, X, XI and XIII, antithrombin III, protein C and plasminogen, and for antigen levels of fibrinogen, prothrombin fragment 1 + 2 (F1 + 2), FIX, protein C, tissue-type plasminogen activator (tPA), plasminogen activator inhibitor 1 (PAI-1) and tPA/PAI-1 complex.
  
  
  RESULTS
  Plasma levels of most coagulation factors, particularly for fibrinogen and FIX antigens as well as FXIII activity significantly increased with aging in sedentary men, while that tendency disappeared in physically active men. By the exercise training, plasma antigen and/or activity levels of most blood coagulation factors except for prothrombin and FIX decreased. These training-effects, however, disappeared after detraining, and in some cases even rebounded to higher levels than those of pre-training. Plasma antigen levels of tPA, PAI-1 and tPA/PAI-1 complex decreased with the training and remained low even after detraining.
  
  
  CONCLUSIONS
  Regular aerobic exercises give complex effects on expression of hemostatic factors, overall favoring the hemostatic balance to less thrombotic, partly cancelling out the age effects.
authors.affiliation: Institute for Human Science and Biomedical Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 6, Tsukuba, Ibaraki 305-8566, Japan. jun.sugawara@aist.go.jp
authors.forename: Jun
authors.initials: J
authors.lastname: Sugawara
authors.forename: Koichiro
authors.initials: K
authors.lastname: Hayashi
authors.forename: Sumiko
authors.initials: S
authors.lastname: Kurachi
authors.forename: Taku
authors.initials: T
authors.lastname: Tanaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Yokoi
authors.forename: Kotoku
authors.initials: K
authors.lastname: Kurachi
mesh_terms: D000328:Adult; D000367:Age Factors; D001779:Blood Coagulation Factors / Q000378:metabolism*; D016022:Case-Control Studies; D015444:Exercise / Q000502:physiology*; D005342:Fibrinolysis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult