You might have diarrhea after working out due things like fluctuating digestive hormones, reduced digestive blood flow, and abrupt movements to your digestive organs.

Certain types of exercise cause food to pass through your digestive tract faster than normal. This can cause reduced intestinal absorption of nutrients, less water being reabsorbed by the colon, and looser stools.

Diarrhea commonly occurs in people who run long distances, especially marathons. People who work out for long periods are also apt to experience diarrhea. It often occurs during or after intense forms of exercise such as running, weightlifting, and cycling.

Though it’s not convenient, diarrhea connected to working out is relatively normal and usually isn’t a cause for concern. Luckily there are things you can do to manage your symptoms and lessen their severity.

Usually, diarrhea related to working out is caused by intestinal blood flood that slows down and is directed away from the intestines. Instead, the blood flows goes toward your legs or other parts of your body.

You may also experience abdominal pain, nausea, and vomiting. Here are some of the ways that certain activities affect digestion during workouts.

After ab workouts

Stimulating and putting pressure on your digestive organs during ab workouts can cause intestinal issues, such as diarrhea and stomachaches. This is especially common if you’re targeting your lower abdominals. Allow for periods of muscle relaxation during these types of workouts.

After running

Many runners experience diarrhea during or immediately following a long-distance run. Moving your body up and down can stir up your digestive system, causing you to have to go to the bathroom more often.

You may also experience cramping, gas, and acid reflux. This happens partly because your blood flow is redirected to your legs instead of your digestive system.

After strenuous exercise

Diarrhea and digestive conditions such as leaky gut are prevalent in people who do strenuous exercise for long periods. This includes swimmers, cyclists, and triathletes. Vigorous activities such as aerobics, dancing, and skiing can also cause digestive upset.


Losing water and fluids through exercise can cause dehydration and diarrhea. Get plenty of healthy fluids before, during, and after your workouts. Replenish lost fluids with water and healthy drinks such as coconut water, broth, and fruit juices.

When pregnant

Diarrhea and other digestive concerns often occur during pregnancy, especially as your due date nears. If you’re already experiencing digestive issues during pregnancy, working out may exacerbate your symptoms.

Keep in mind that it could be unrelated to exercise. Fluctuating hormones, increased stress levels, prenatal vitamins, or developing new food sensitivities can also cause diarrhea during pregnancy.

Use caution with your exercise routine during pregnancy and notice any digestive changes, including diarrhea. Treat diarrhea as soon as possible since it’s especially important to maintain proper fluid levels.

Usually, diarrhea clears up on its own within a few days and isn’t a cause for concern, but you can still try various treatments to speed up your recovery.

Eat certain foods

Eat easily digestible foods that don’t stimulate or irritate digestion. Follow the BRAT (bananas, rice, applesauce, and toast) diet when you’re working out a lot or have symptoms arise.

Other suitable foods include vegetable soup, lean meats, and potatoes. To replenish healthy gut bacteria, take a probiotic supplement or eat probiotic-rich foods such as plain yogurt, sauerkraut, or tempeh. Include drinks such as kombucha, kefir, and kvass.

Schedule your workouts

If you have regular bowel movements, schedule your workouts after you’ve had one. If you’re unsure of your habits, keep track for a few days to see if you notice a pattern. Design your running route so that you have access to a restroom at a set time into your run.

Reduce intensity

If you’re having a bout of diarrhea, you can try reducing the intensity or duration of your workout to better manage your symptoms. Experiment to see which methods or changes work best to get your digestion under control before returning to full-power workouts.

Try OTC medications

Over-the-counter medicines such as loperamide (Imodium) or bismuth subsalicylate (Pepto Bismol) are also options. It’s not advised to take these often, but you may consider using them on occasions such as race or competition days.

Avoid any problematic foods for 3 to 6 hours before you run. Don’t eat anything for at least 2 hours before you run.

Things to avoid:

  • gas-producing foods and beverages, such as high-fiber foods like beans, bran, and fresh fruits and vegetables
  • fried, high-fat, and spicy foods and protein powders that upset your stomach
  • dairy products, as the effects of lactose intolerance can be intensified during workouts
  • caffeinated, carbonated, or warm beverages, and sports drinks sweetened with fructose and artificial sweeteners, such as isomalt, mannitol, or sorbitol
  • medications such as ibuprofen (Advil), naproxen (Aleve), aspirin, or antibiotics
  • wearing bike shorts, leggings, or other tight clothing, as it can limit blood flow to your digestive system; instead wear loose-fitting clothes and avoid anything that’s too tight around your waist.
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Severe or long-lasting diarrhea can affect your workouts and quality of life, plus it can be a sign of a serious illness.

Talk to your doctor if you have diarrhea that happens frequently or lasts for more than two days. It could be a sign of something more serious, such as an infection or irritable bowel syndrome (IBS).

Dehydration is a concern for people who are very old, very young, or very sick, since it’s more difficult for them to replenish lost fluids. Those people should seek medical attention if they have long-lasting diarrhea.

See your doctor if you have persistent diarrhea that is accompanied by these signs and symptoms of dehydration:

  • dark yellow or orange urine
  • unusual urine odor
  • infrequent urination
  • rapid heart rate
  • feeling lightheaded or dizzy
  • headache
  • dry mouth
  • flushed, dry skin
  • irritability or confusion
  • fever
  • bleeding

Diarrhea related to working out is normal, especially among runners, elite or endurance athletes, and people who engage in intense exercise.

Monitor the effect that working out has on your digestion and adjust accordingly, whether that involves making changes to your diet, schedule, or fitness routine.