b'EXERCISE-INDUCED GASTROINTESTINAL SYNDROMERedistribution of blood flow and increased sympathetic drive during prolonged, strenuous exercise can alter the absorptive capacity of the gut. This can induce upper (belching, reflux, poor tolerance and nausea) and lower (flatulence, lower abdominal bloating and pain, cramping or urge to defecate) GI symptoms, and limit the delivery of exogenous carbohydrate to the working muscles 6 . REDISTRIBUTION OF BLOOD FLOW MECHANICAL FORCE AND SHEAR STRESSDuring exercise, blood flow is redirected to the workingMechanical forces during exercise have also been highlighted muscles to deliver increasing oxygen and nutrient demands.as a possible contributing factor to such problems. The Research has shown that 1 hour exercise at 70% VOwilljarring, jolting and friction that occurs during running and 2maxreduce splanchnic perfusion by up to 80% 30 . Exercising in highsimilar load bearing activities, as well as the kinking of the GI temperatures or when dehydrated will reduced blood volumetract in the cycling position, is thought to induce or contribute and further exacerbate hypoperfusion of the gut. Ischemicto GI symptoms. damage and erosion of epithelial cells as a result of oxygen and nutrient deprivation stimulates a local inflammatory response. Ischemia and the local inflammatory response damages multi-protein complexes and tight-junction regulatory proteins of the epithelium. Bacteria, bacterial endotoxins and other pathogenic agents can enter circulation via physical breaks in the epithelium, further exacerbating local and systemic inflammatory responses.INCREASED SYMPATHETIC DRIVEAt the onset of exercise, there is an increase in circulation of stress hormones (i.e., cortisol and adrenaline). Gastric motility, gastric emptying and translocation of epithelial transporters is reduced, resulting in overall reduced GI functional capacity. This can lead to upper GI symptoms such as poor tolerance to food and drinks, belching and reflux, as well as lower GI symptoms as a result of nutrient malabsorption. 14'