RUNNER'S DIGEST——From the May 2010 issue of Runner's World

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RUNNER'S DIGEST
Changing what—and when—you eat can halt all kinds of midstride GI trouble.By Liz Applegate Ph.D.

At some point, everyone suffers midrun stomach problems, whether it's a sharp pain that forces you to walk or the sudden need to find a porta-potty stat. Luckily, there's a cure for whatever ails you. Here's how to identify any digestive issue that might slow you down—and prevent it from wreaking havoc on your next run.

Sharp stomach pain and burping while running
CULPRIT Runners who get pre-race nerves, drink carbonated beverages, or chew gum often swallow air, causing belching and pains that mimic heartburn or a heart attack.
FOOD FIX Pass on fizzy drinks and gum pre- and midrun. Eat slowly to avoid swallowing air. If you get prerace nerves, take slow, relaxed breaths to avoid trapping air in your stomach.

A burning feeling in your chest that can occur while running
CULPRIT Called heartburn, acid reflux, and "GERD," gastroesophageal reflux disease occurs when stomach acid hits the esophagus.
FOOD FIX Eat a few small meals, not one large one; wait three hours after eating to run. Don't lie down after a meal (it can prompt reflux). Avoid trigger foods such as mint, coffee, and spicy dishes.

Excessive gas and bloating
CULPRIT When intestinal bacteria try to break down fiber and other indigestible carbohydrates, they produce gas. Eating lots of fiber creates excessive gas and bloating.
FOOD FIX A full day prior to a race, back off high-fiber foods, such as whole grains, beans, and bran cereals, as well as the problematic foods listed in "Unusual Suspects" (below).

Excessive gas, bloating, and occasional diarrhea
CULPRIT Symptoms may be caused by lactose intolerance, an inability to digest lactose in dairy.
FOOD FIX Cut out dairy, or buy lactose-free versions (some people with lactose intolerance can handle yogurt and kefir). Take Lactaid or other enzyme pills to help your body digest dairy.

A sudden midrun need to hit a bathroom
CULPRIT The gut receives less blood midrun, causing poor GI function—earning this malady its nickname, the "runner's trots." The longer your run, the more likely you'll experience it.
FOOD FIX Avoid high-fiber foods 24 hours before running. Pass on coffee (it stimulates intestinal motion). Dehydration and too many midrun carbs worsen the problem; don't exceed 30 to 60 grams of carbs per hour.

An urgent need for a bathroom when not running
CULPRIT Gluten is a wheat protein some people can't digest, causing gas, bloating, and diarrhea.
FOOD FIX If you suspect gluten intolerance, see a doctor for a diagnosis, and only eat gluten-free foods. However, if you have severe abdominal cramps or blood in your stool, see a physician immediately. You may have a more serious digestive disease or colon polyps, which require treatment.



Unusual Suspects

Having GI problems? Cut back on these runner faves

BROCCOLI, MELON, AND BELL PEPPERS
These fruits and vegetables contain gas-forming, indigestible carbohydrates that cause painful bloating midrun.

FIBER-FORTIFIED FOODS
The added fiber in breads, tortillas, yogurt, crackers, and other foods can create bulkiness in the colon, gas, and loose stools.

ICE CREAM
Compared to other dairy, this sweet dessert is particularly high in lactose and can cause trouble for lactose intolerant people.

NSAIDS
Aspirin, ibuprofen, and other nonsteroidal anti-inflammatory drugs can irritate the stomach, and in extreme cases even cause intestinal bleeding.

JUICE AND ENERGY DRINKS
They contain a high concentration of carbs and when drunk before or midrun can cause stomach cramps.

CAFFEINE
It can stimulate the intestinal tract. Cut back on caffeine sources like coffee and tea. Check other drinks, foods, and medications for caffeine content.