DEAR DR. DONOHUE: It is my wish to run at least one marathon before I die. I am training now and plan to run the race in the late spring. Lately while running I feel sick to my stomach, and I have to be near a bathroom because I get diarrhea. How do I stop this? – W.W.

Yours is a common story among runners. Prolonged and intense exercise can lead to symptoms in the upper gastrointestinal tract or the lower tract. Upper tract symptoms include bloating, heartburn, nausea and sometimes vomiting. Diarrhea is a lower tract symptom. You are most unfortunate. Most runners have either the upper symptoms or the lower symptoms but not both.

One explanation for these symptoms invokes shunting of blood away from the digestive tract. Leg muscles demand more blood when a person runs, and the best place to take it from happens to be the gastrointestinal tract. Robbing the tract of blood leaves it filled with only partially digested food. That can cause both upper and lower tract troubles.

Cut down on your distance until all symptoms have gone. When you reach that distance, stay at it for two weeks. Then gradually increase the distance. The digestive tract adapts to new challenges if you give it a chance.

Stop eating four hours before you run. You might try taking only liquid or soft meals at that time. Once the digestive tract has learned how to cope with the stress of running, you can begin to add solids to the pre-run meal.

Before your run, don’t take any medicines that can irritate the stomach – aspirin or anti-inflammatory drugs.

About half an hour before you run, drink 7 ounces (200 ml) of a sports drink that contains no more than 8 percent carbohydrates.

DEAR DR. DONOHUE: I take medicine for angina. I have had no chest pain for more than six months. My doctor has permitted me to begin a jogging program, and it causes me no trouble. I would also like to build muscle. Is it safe for someone like me to lift weights? – C.I.

If you had asked this question 10 years ago, you would have gotten a resounding no. Weightlifting causes a rise in blood pressure, and the rise can push the pressure to well over 200. That’s a level that puts a good deal of stress on the heart.

Now the attitude on weightlifting for heart patients is more liberal. People who have angina or who have had a heart attack have been studied in carefully monitored weightlifting programs. The exercise has been found to be safe, but you have to abide by some rules.

Determine the most weight you can lift one time by experimenting with different weights. When you find that amount, take 40 percent of it and then lift the weight eight times. Take a break and do another series of eight lifts. When you can lift the weight 15 times without straining, you can increase the amount you lift by 5 percent or 10 percent.

Many heart doctors encourage their heart patients to engage in weightlifting. It builds stronger bones, a definite plus for women who are at risk for osteoporosis. It builds muscle strength and size. It raises the basal metabolic rate so more calories are burned even when resting. That keeps body weight at a desirable level.

The last and most important rule is not to even think about doing this without clearance from your doctor.

DEAR DR. DONOHUE: How many steps are in a mile? I jog through the woods, and I cannot get an accurate measurement of the distance I am running. – P.P.

There are about 2,000 to 2,500 steps in a mile. The number depends on the length of your stride. If you have to count every step you take, that must drive you crazy. You can get a pedometer from most sporting-goods stores that keeps track of the number of steps you take.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475.

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