A mysterious Colorado jogger has taken the internet by storm recently. Security cameras have recorded the woman repeatedly pooping on the same residential lawn. Theories about The Mad Pooper’s motives abound. Maybe someone made her angry. Maybe she’s confused.

Maybe she just couldn’t hold it.

We all know it’s wrong to heed the call of nature in plain sight, but many athletes can relate to belly woes during long, hard workouts. In fact, 50 percent of all athletes say they have experienced gastrointestinal (GI) symptoms at some point while training.

Unfortunately, nausea, vomiting, reflux and diarrhea aren’t always avoidable, but a few simple strategies can help. Here are five tips for minimizing digestive distress during exercise.

Hydrate Right
It’s easy blame food when your belly is angry, but many gastrointestinal issues stem from fluid imbalances.

“Improper fluids, not foods, are often the culprit of GI distress during exercise, especially if exercise is intense,” said Jennifer McDaniel, certified specialist in sports dietetics and founder of McDaniel Nutrition Therapy in St. Louis.

During exercise, the body undergoes changes that favor the muscles over the GI tract. One such change is a reduction in blood flow to the gut, which can alter the rate of digestion.

Dehydration further impairs digestive function and may even damage the intestinal tissues. Therefore, it’s important to hydrate before, during and after athletic events to ward off distress.

The American College of Sports Medicine (ACSM) suggests:

  • 16 to 20 ounces of water or sports drink at least four hours before exercise;
  • 8 to 12 ounces of water 10 to 15 minutes before the start of an event;
  • 3 to 8 ounces every 15 to 20 minutes during exercise, with no more than 1 liter of fluids per hour.

Water is fine for shorter workouts. Sports drinks can replace carbohydrates and electrolytes during workouts longer than one hour.

Finally, it’s important to replace fluid losses within two hours of finishing an event. Most people can gauge hydration by looking at urine color. Urine that’s darker than lemonade indicates dehydration.

Put Down a Good Base
It may be tempting to work out on an empty stomach if you’re prone to digestive discomfort, but this approach may backfire. Exercising on an empty stomach increases risk for hypoglycemia, which can result in nausea and vomiting.

Still, certain foods may also cause nausea, vomiting, diarrhea and acid reflux.

So, what should you eat before a workout? It depends on your activity, your GI concerns and how much time you have to digest beforehand.

Meals eaten an hour or less before activity should be light and easy to digest. A banana and a sports drink provide energy for training without overloading the gut. A larger meal, like a bagel with peanut butter and banana, is appropriate when you have a couple of hours to digest.

Those with frequent GI distress should be extra careful when planning pre-workout meals. High-fat and high-fiber foods can worsen diarrhea in athletes who are prone to it. Try limiting fiber for a day or two and reducing high-fat foods for a few hours before intense exercise.

Several foods are also linked to acid reflux. These include high-fat foods, spicy foods, caffeine and protein-rich foods. Athletes with reflux should eat smaller meals and limit problem foods before workouts.

Be Choosy with Your Fuel
Many athletes use energy gels and chews for a boost during long workouts, but the same ingredients that improve performance may wreak intestinal havoc.

Fructose is a frequent offender. Those with fructose malabsorption don’t completely digest fructose in the small intestine. When this happens, fructose molecules undergo fermentation in the colon. Diarrhea and cramping are common symptoms. Sugar alcohols — including sorbitol and xylitol — can cause a similar effect.

To some extent, proper usage of these products can prevent GI distress. Always take gels and chews with a few swigs of water to speed up digestion and absorption. And never chase them with sports drink. The combination of gels and sports drink is too much simple sugar for the gut to handle at once.

Interestingly, a 2014 study found that athletes can train the gut to tolerate simple sugars during exercise. That’s not to say you should stick with a supplement that often causes severe GI symptoms. (It may be helpful to try products with maltodextrin or other sugars during training workouts.) But athletes with mild symptoms can increase supplement dose gradually over several workouts. Doing so may improve tolerance over time.

Calm Down
Does the sound of a race starting gun send you into a mad dash…to the Porta Potty? Blame your nerves.

Your gut has millions of neurons that communicate with the central nervous system. These neurons can alter digestive function when you’re stressed or anxious.

Slowing down and breathing can help to calm your belly and your brain before a sporting event.

“Try mindful breathing in the morning or before the athletic event for just a few minutes each day,” said Julie Lazaroff, a yoga instructor in St. Louis. “Come to a comfortable seat, close your eyes, relax your face and your jaw, and bring length into your spine. Take a moment and become aware of the feeling inside your body. Notice any emotions that are present. Turn your attention towards your breath. Watch your breath as it comes in and out of your nostrils. With relaxed effort, gradually begin to deepen the breath. Keep focusing on your breath entering and exiting the body smoothly.”

Additionally, reflect on how well-prepared you are for the event. Doing so can help calm the nerves.

Get Help
GI distress during exercise is uncomfortable at best. Simple diet and lifestyle changes can prevent most mild symptoms, but severe symptoms warrant professional help.

Speak with your doctor if you often vomit or have reflux during exercise, or if you have bloody stool. He or she can rule out or treat any underlying medical causes. Once you’re medically cleared, a sports dietitian can troubleshoot mild to moderate symptoms and help you avoid your own Mad Pooper moments.

Kimberly Yawitz is a registered dietitian and freelance writer who enjoys trail and obstacle course races, paddling and Crossfit. You can read more of her work at dietvsdisease.com and in the St. Louis Track Club newsletter.