title: Cardiac biomarkers and exercise duration and intensity during a cycle-touring event.
abstract: OBJECTIVE
  To determine the influence of age, training status, race time, and exercise intensity on the appearance of cardiac biomarkers after a cycle-touring event.
  
  
  METHODS
  Pre-post exercise measurements.
  
  
  METHODS
  University of Zaragoza, Zaragoza, Spain.
  
  
  METHODS
  Ninety-one amateur cyclists.
  
  
  METHODS
  The 2005 Quebrantahuesos cycle-touring event (distance: 206 km; altitude difference: 3800 m).
  
  
  METHODS
  Cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) were measured the day before and immediately after the race. Heart rate (HR) monitoring was performed on 55 cyclists during the race to evaluate exercise intensity.
  
  
  RESULTS
  cTnI and NT-pro-BNP were significantly elevated immediately post race, with 43% of participants exhibiting cTnI levels greater than 0.04 microg/L and 65% of the participants measuring NT-pro-BNP levels greater than 125 ng/L. The cTnI increase was significantly associated with mean exercise intensity HR (r = 0.36, P < 0.01) but was not associated with age, training status, or race time. The increase in NT-pro-BNP correlated with race time (r = 0.40, P < 0.001) and training status (r = -0.36, P < 0.001) but was not associated with age or exercise intensity HR measures.
  
  
  CONCLUSIONS
  These results suggest that, in part, exercise intensity (HR) is responsible for the cTnI increase and that race time is responsible for the increase in NT-pro-BNP. Future standardized endurance exercise trials are recommended to further elucidate the potentially differential effects of training status, exercise time, and intensity on post-exercise increases in cTnI and NT-pro-BNP.
authors.affiliation: Section of Physical Education and Sports, University of Zaragoza, Zaragoza, Spain. enrise@unizar.es
authors.forename: Enrique
authors.initials: E
authors.lastname: Serrano-Ostáriz
authors.forename: Alejandro
authors.initials: A
authors.lastname: Legaz-Arrese
authors.forename: José Luis
authors.initials: JL
authors.lastname: Terreros-Blanco
authors.forename: Marta
authors.initials: M
authors.lastname: López-Ramón
authors.forename: Daniel
authors.initials: D
authors.lastname: Cremades-Arroyos
authors.forename: Luis Enrique
authors.initials: LE
authors.lastname: Carranza-García
authors.forename: Silvia
authors.initials: S
authors.lastname: Izquierdo-Alvarez
authors.forename: Silvia
authors.initials: S
authors.lastname: Alvarez-Izquierdo
authors.forename: Pilar
authors.initials: P
authors.lastname: Bocos-Terraz
authors.forename: Pilar
authors.initials: P
authors.lastname: Boscos-Terraz
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D015415:Biomarkers / Q000097:blood; D006335:Heart Injuries / Q000175:diagnosis / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D013030:Spain; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D019210:Troponin I; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain