Liver overload in Brazilian triathletes after half-ironman competition is related muscle fatigue

Ann Hepatol. 2008 Jul-Sep;7(3):245-8.


Triathlon competition is dependent on the athletes' ability to perform each discipline at optimal time, without excessive fatigue influencing the next one.

Objectives: Determine the effects of a long distance triathlon on biochemistry parameters related to liver function.

Design and methods: Blood samples from six athletes were collected before (T = 0) and immediately after the triathlon competition (T = 1). AST, ALT and alkaline phosphatase (ALP) values were assessed.

Results: Significant changes after triathlon competition were found for AST and ALP and no significant changes were found for ALT over time.

Conclusions: A series of metabolically alterations, mainly related to energy production and also to muscle and skeletal adaptations occurs during and after strenuous exercise. The altered status of those metabolical changes cannot directly reflect the intensity of any possible muscular or hepatic damage or overload and elevated AST/ALT ratio is better associated to skeletal muscle lesion during competition.

MeSH terms

  • Adaptation, Physiological
  • Adult
  • Alanine Transaminase / blood
  • Alkaline Phosphatase / blood
  • Aspartate Aminotransferases / blood
  • Bicycling*
  • Brazil
  • Energy Metabolism
  • Humans
  • Liver / enzymology*
  • Male
  • Muscle Fatigue*
  • Muscle, Skeletal / metabolism*
  • Physical Endurance*
  • Running
  • Swimming
  • Time Factors
  • Young Adult


  • Aspartate Aminotransferases
  • Alanine Transaminase
  • Alkaline Phosphatase