Bizarre things exercise does to your body

You feel like someone is stabbing a knife into your ribs. Experts don’t know exactly what causes those sharp, fleeting pains called side stitches, but many believe they’re due to diaphragm spasms triggered by rapid breathing, says Tom Holland, exercise physiologist and author of Beat the Gym. Eating too close to your workout may play a role. And side stitches occur more frequently in novice exercisers.

What to Try: To stop a stitch, slow your pace and take deep breaths while contracting your abdominal muscles. Stretch your arms overhead or to the side. To prevent a stitch: Eat light pre- exercise meals, and wait at least 30 minutes after eating before you work out. Always warm up for five to ten minutes; gradually increase workout intensity.

Your nose is suddenly a leaky faucet. Exercise, especially in cold, dry air, can trigger a runny, congested nose, a condition known as exercise-induced rhinitis. “Increased nasal breathing during exercise dries out the nose’s mucous membranes, which makes the nose secrete more mucus to protect the nasal airway,” says William Silvers, MD, of Allergy Asthma Colorado in Englewood.

What to Try: If your nose is really interfering with your workout, ask your doctor to prescribe a nasal spray, and use it at least 30 minutes before you exercise. Pack plenty of tissues in your pockets.

You have to go the bathroom. Badly. It’s called runner’s trots, but don’t be fooled by the name: Even walkers can experience loose bowels, especially when logging long distances. During exercise, your body directs blood flow away from your gut to working muscles, which can trigger diarrhea, Holland says. Dehydration and pre-race anxiety may exacerbate the problem.

What to Try: Don’t eat anything for two hours before exercising. Skip high-fiber and high-fat foods, caffeine, and artificial sweeteners, all of which can make things worse. Drink plenty of fluids before, during, and after exercise. Begin your workouts after bowel movements, and make sure you have access to a restroom.

Your face turns as red as a stop sign. Blame your capillaries, small blood vessels near the skin’s surface that dilate during exercise to help you stay cool. People with sensitive skin may flush more and stay red longer.

What to Try: Spritz cold water on your skin frequently or switch to activities in air-conditioned locations. The flush usually dis­appears about 30 minutes after you stop exercising, but if you have persistent redness, you may have rosacea, a skin disease that causes flushing, redness, bumps, and pimples. It can be treated with oral and topical medications.