Exercise and gastrointestinal function and disease: an evidence-based review of risks and benefits.
OBJECTIVE
Exercise is beneficial to health because it reduces the risk of cardiovascular and endocrine diseases, improves bone and muscle conditioning, and lessens anxiety and depression. However, the impact of exercise on the gastrointestinal system has been conflicting. This systematic literature review evaluates the effect of the different modes and intensity levels of exercise on gastrointestinal function and disease using an evidence-based approach. Although more applicable to trained athletes and individuals who are highly active and, as such, at risk to experience the side-effects of exercise, an effort was made to state the level or degree of exercise or the lack of such evidence.


RESULTS
Light and moderate exercise is well tolerated and can benefit patients with inflammatory bowel disease and liver disease. Physical activity can also improve gastric emptying and lower the relative risk of colon cancer in most populations. Severe, exhaustive exercise, however, inhibits gastric emptying, interferes with gastrointestinal absorption, and causes many gastrointestinal symptoms, most notably gastrointestinal bleeding.


CONCLUSIONS
This knowledge will enable physicians to prescribe physical exercise in health and disease and to better manage patients with exercise-related gastrointestinal disorders. Our understanding of exercise and its gastrointestinal manifestations as well as risks and benefits warrants further investigation.
Bi
Luke
L
Division of Gastroenterology, Department of Medicine, College of Medicine, University of California at Irvine, Orange, CA, USA.
Triadafilopoulos
George
G
D004064:Digestive System / Q000503:physiopathology; D004068:Digestive System Physiological Phenomena; D019317:Evidence-Based Medicine; D015444:Exercise; D005744:Gastric Acid / Q000378:metabolism; D005746:Gastric Emptying; D005767:Gastrointestinal Diseases / Q000503:physiopathology* / Q000628:therapy; D006801:Humans; D018570:Risk Assessment