Gastrointestinal Symptoms and Altered Intestinal Permeability Induced by Combat Training Are Associated with Distinct Metabotypic Changes.

Physical and psychological stress have been shown to modulate multiple aspects of gastrointestinal (GI) physiology, but its molecular basis remains elusive. We therefore characterized the stress-induced metabolic phenotype (metabotype) in soldiers during high-intensity combat training and correlated the metabotype with changes in GI symptoms and permeability. In a prospective, longitudinal study, urinary metabotyping was conducted on 38 male healthy soldiers during combat training and a rest period using gas chromatography-mass spectrometry.

Combat-training stress in soldiers increases S100B, a marker of increased blood-brain-barrier permeability, and induces immune activation.

Background: Experimental data suggest stress-related cognitive dysfunction may be associated with increased blood-brain-barrier (BBB) permeability secondary to immune activation.

Methods: We investigated the relationship between prolonged and intense physical and psychological combat-training stress, immune activation and blood-brain-barrier permeability in 37 healthy male army medical rapid response troops.

Results: Soldiers during intense combat training showed greater self-reported stress, anxiety and depression levels than at rest, as assessed by specific questionnaires.