Introduction
intestinal barrier dysfunction, GI distress
PHYSIOLOGICAL STRESS, INTESTINAL BARRIER DYSFUNCTION, INFLAMMATION
The gastrointestinal (GI) barrier is comprised of simple columnar epithelial cells densely held together by tight junction proteins [Intestinal barrier dysfunction can result from psychological or physiological stress [In this regard, several dietary supplements have been tested for their effects on exercise-induced GI distress. While most studies focus on which supplements could minimise intestinal barrier dysfunction and therefore reduce the prevalence and severity of GI distress, several studies have also established which foods or supplements may aggravate GI distress and should therefore be avoided prior to exercise [A novel strategy is the use of collagen peptides (CP), which contain high amounts of the amino acids glycine, hydroxyproline and proline. Intact collagen is the major component of the extracellular matrix in the body. In a recent in vitro study [To date, however, no study has evaluated the effects of CP on GI integrity, permeability, or symptoms in exercising humans. Consequently, the aim of the present study was to examine whether supplementation with CP before high intensity running exercise can affect markers of inflammation, intestinal barrier dysfunction and subjective GI symptoms. As CP are increasingly being used by athletes [