The gastrointestinal system is made up of the oesophagus, stomach, liver, gall bladder, pancreas, small intestine and large intestine. It functions to digest the food, absorb nutrients and help remove waste from the body. Exercise brings many beneficial effects, such as tighter glucose control in diabetic patients, better sleep habits, stronger bones, and in relation to the gastrointestinal system, improved gut movement that helps prevent constipation. However, too much exercise, especially strenuous activity, may place excessive stress on the gastrointestinal tract, and may aggravate symptoms of gastrointestinal disorders such as Crohn’s disease, ulcerative colitis, and irritable bowel syndrome (IBS). This may lead to nausea, diarrhoea, acid reflux, constipation and even cramps. It is important to understand why these symptoms may happen during exercise, and plan how you exercise in order to reduce discomfort.