The Effects of Sports on the Gastrointestinal Tract

Although moderate-intensity exercise can prevent gastrointestinal problems, too much intensity can cause problems in your gastrointestinal tract. For professional athletes, 25 to 50 percent suffer from gastrointestinal problems so severe their training or performance at events is affected, according to research led by London South Bank University professor Rita de Oliveira, writing in the journal "Current Opinion in Clinical Nutrition & Metabolic Care." To avoid gastrointestinal distress, watch for signs you are overdoing it and adjust your workout accordingly.

Positive Effects

• Mild- to moderate-intensity exercises play a protective role against colon cancer, diverticular disease, cholelithiasis and constipation, according to researcher de Oliveira. There are short-term positive effects as well. When you first begin to move your body your bowel is stimulated, which helps clean your bowels and alleviate constipation. Sports that require an upright posture, such as jogging and running, help the body expel gas, alleviating pressure and bloating. "Eating and exercise go hand in hand," according to MayoClinic.com, so those who are active tend to follow a healthy diet rich in fiber, which promotes a healthy gastrointestinal tract.

Negative Effects

• Being overly active in sports can actually be bad for your gastrointestinal health. Overdoing it can cause symptoms including diarrhea, incontinence, stomachache, reflux, cramps and rectal bleeding. Women are particularly susceptible, according to the Journal "Sports Medicine." Under severe stress, such as an ultra-marathon, as many as 40 to 50 percent of all athletes defecate during the race, as documented by fitness expert and lead author Martin Schwellnus in the 2008 edition of The Encyclopaedia of Sports Medicine. Overdoing it during recumbent exercises, such as cycling and board surfing, can cause esophageal reflux. A decrease in intestinal blood flow associated with vigorous exercising can cause nausea, vomiting and gastric ulcers.
• Warning Signs

• Consult a physician if you are experiencing chronic heartburn, nausea, vomiting, abdominal cramps or diarrhea. Get a medical checkup immediately if you are experiencing sudden or severe weight loss, high fever, coughing up blood or bruising easily, which may be signs of internal bleeding. Be especially vigilant if you have been an athlete for your entire life without experiencing any gastric upset, and all of a sudden develop gastrointestinal symptoms after the age of 40, according to Schwellnus.

Treatment

• If you are experiencing gastrointestinal problems after working out, cut down on the intensity level, according to de Oliveira. Make sure to drink plenty of water before, during and after exercising, to ensure that your gastrointestinal problems are not made worse by dehydration. Cut down on high-fiber foods until your symptoms subside, according to MayoClinic.com. If nothing has changed about your workout regimen, but you have recently starting taking a new medication, talk to you doctor. It may be the new medication, rather than exercise, that is the culprit. If problems persist despite training and lifestyle modifications, you doctor can prescribe medication to help ease the symptoms.