Question: I sometimes get some blood in my stool after a long run. Is this something I should be concerned about? I know runners who get other stomach problems when they train hard. Could you say something about this, too?
Answer: Exercise is good for the gut. This has been known for a long time. For instance, John Puch, in his 1794 Treatise of the Science of Muscular Action, said, "Exercise helps to throw down wind from the bowels and attenuates the contents of the stomach."
Nevertheless, many distance runners complain of diarrhea, stomach pain, bloating, belching, nausea, vomiting, heartburn and rectal bleeding, as well as irritable bowel syndrome. Irritable bowel syndrome is a combination of stomach pain with constipation or diarrhea, or sometimes both, alternating.
Any one of these gastrointestinal disturbances, particularly blood in the stool, can be an indicator of something serious and should be brought to a doctor's attention. Fortunately, however, they are usually not life-threatening signs, and they often respond well to the following simple treatments.
The occasional use of antacids for heartburn and diarrhea drugs often helps. But emphasis here is on occasional _ read the warnings on the labels. The timing, amount and content of food and fluids taken before a workout or a race are also important. What's recommended is a light carbohydrate meal two to four hours before the exercise, followed by 16 ounces of cool water 20 to 30 minutes prior to the activity, and another four to eight ounces every 10 to 15 minutes into the run. Many runners prefer glucose drinks, to supply extra carbohydrate calories, or electrolyte-supplemented sports drinks. A glucose concentration of up to 10 percent does not usually cause stomach disturbances, nor do sport drinks such as Gatorade.
Some runners find that high-fiber diets, milk, fruit, and perhaps other foods contribute to their problem. The obvious solution here is, before workouts or competition, to avoid those items that may aggravate your gut. In addition, gut discomfort is often associated with increases in training and with very hard runs _ another good reason always to gradually increase running loads.
Hearts and iron
Question: I am a female triathlete and have been taking iron supplements to avoid anemia. But I read recently that high amounts of iron in the body may cause heart disease. Can you explain this?
Answer: A recent study of almost 2,000 Finnish men found that the men with high concentrations of iron in their blood were twice as likely to have a heart attack as those with lower values. This is the first time this relationship has been found. The scientists speculate that too much iron may promote the formation of free radicals. These are rogue molecules that can injure the cells lining the artery walls, damage the heart muscle and increase artery-clogging LDL-cholesterol.
The results of this study must be confirmed and duplicated using women before nutritionists will make recommendations about dietary iron or supplements. But regardless of the outcome, you may want to stop iron supplements.
Iron supplements are usually a waste of money. Most people get plenty of iron from a balanced diet that includes liver, eggs, fish, green leafy vegetables, nuts and beans. Supplements are not needed unless prescribed by a doctor for iron deficiency anemia, which usually results from abnormal bleeding (heavy periods or a peptic ulcer), fetal demands during pregnancy or severe dieting.
Write with questions to Dr. Patrick J. Bird, Dean of the College of Health and Human Performance, University of Florida, Gainesville, FL 32611.
The Health & Fitness pages are coordinated by Jim Melvin. Comments may be addressed to: Jim Melvin, in care of the Times, Floridian, P.O. Box 1121, St. Petersburg, FL 33731.