title: Impact of aerobic exercise on haemostatic indices in paediatric patients with haemophilia.
abstract: This study investigated the impact of aerobic exercise on laboratory assessments of haemostatic activity in boys (5-18 years of age) with haemophilia A (HA) or B (HB), examining the hypothesis that laboratory coagulation parameters temporarily improve with exercise. Thirty subjects meeting eligibility criteria (19 HA; 11 HB; mean age: 12.8 years) were invited to participate. They underwent a replacement factor washout period and were advised against strenuous activity for three days prior to the planned intervention. At study visit, baseline blood samples were drawn prior to exercise on a stationary cycle ergometer, aiming to attain 3 minutes (min) of cycling at 85 % of predicted maximum heart rate. Blood work was repeated 5 min (t5) and 60 min (t60) post exercise completion. Samples were assessed for platelet count (PC), factor VIII activity (
  
  
  
  C), von Willebrand antigen (VWF:Ag), ristocetin cofactor activity (VWF:RCo) and platelet function analysis (PFA-100); maximum rate of thrombus generation (MRTG) in blood was measured via thromboelastography and plasma peak thrombin generation (PTG) via calibrated automated thrombography. Mean duration of exercise was 13.9 (± 2.6) min. On average, t5 samples showed significant elevation, relative to baseline in PC, FVIII:C, VWF:Ag, VWF:RCo and PTG, while
  
  
  
  C, VWF:Ag, VWF:RCo and MRTG were significantly elevated in t60 samples. Within the cohort, participants with severe HA showed no change in
  
  
  
  C levels with exercise. The greatest improvement in haemostatic indices was observed in post-adolescent males with mild-moderate HA, who thus represent the group most likely to benefit from a reduction of bleeding risk in the setting of exercise.
authors.forename: Riten
authors.initials: R
authors.lastname: Kumar
authors.forename: Vanessa
authors.initials: V
authors.lastname: Bouskill
authors.forename: Jane E
authors.initials: JE
authors.lastname: Schneiderman
authors.forename: Fred G
authors.initials: FG
authors.lastname: Pluthero
authors.forename: Walter H A
authors.initials: WH
authors.lastname: Kahr
authors.forename: Allison
authors.initials: A
authors.lastname: Craik
authors.forename: Dewi
authors.initials: D
authors.lastname: Clark
authors.forename: Karen
authors.initials: K
authors.lastname: Whitney
authors.forename: Christine
authors.initials: C
authors.lastname: Zhang
authors.forename: Margaret L
authors.initials: ML
authors.lastname: Rand
authors.affiliation: Manuel Carcao, MD, MSc, Division of Haematology-Oncology, The Hospital for Sick Children, 555 University Avenue, Toronto, ON - M5G 1X8, Canada, Tel.: +1 416 813 5367, Fax: +1 416 813 5327, E-mail: manuel.carcao@sickkids.ca.
authors.forename: Manuel
authors.initials: M
authors.lastname: Carcao
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001780:Blood Coagulation Tests; D002648:Child; D002675:Child, Preschool; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy; D005169:Factor VIII / Q000378:metabolism; D006467:Hemophilia A / Q000097:blood* / Q000503:physiopathology / Q000628:therapy; D002836:Hemophilia B / Q000097:blood* / Q000503:physiopathology / Q000628:therapy; D006470:Hemorrhage / Q000517:prevention & control; D006487:Hemostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D010865:Pilot Projects; D012307:Risk Factors; D013177:Sports / Q000502:physiology; D013916:Thrombelastography; D014841:von Willebrand Factor / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII
keywords: Haemophilia; exercise; factor VIII