Strenuous exercise causes systemic endotoxemia

Abstract

Eighteen triathletes were studied before and immediately after competing in an ultradistance triathlon. Their mean plasma lipopolysaccharide (LPS) concentrations increased from 0.081 to 0.294 ng/ml (P less than 0.001), and their mean plasma anti-LPS immunoglobulin G (IgG) concentrations decreased from 67.63 to 38.99 micrograms/ml (P less than 0.001). Both pretriathlon plasma LPS and anti-LPS IgG levels were directly related to the intensity of training (P less than 0.02 and P less than 0.01, respectively). It is possible that training-induced stress led to some leakage of LPS into the circulation, which, in turn, resulted in self-immunization against LPS. The effects on athletic performance in relation to exercise-induced changes in plasma LPS and anti-LPS IgG levels require further investigation.