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10 Causes of Stomach Pains When Running & Prevention Options

This is a fairly common phenomenon among athletes. In fact, research indicates that about 30–90% of distance runners develop gastrointestinal (GI) disturbances due to exercise.

Stomach pains when running can be devastating, especially when you don’t know how to prevent them. The experts at HIGH5 have put together this detailed guide to explain the mystery behind runner’s tummy, potential triggers, and management options.

What Is a Runner's Tummy?

You’ve probably been there: out for a long run, then your stomach starts churning and gurgling, triggering the dreaded “runner’s trots” strike that sends you scrambling for the nearest restroom.

Runner’s tummy, also known as runner’s diarrhoea or runner’s trots, refers to the uncomfortable gastrointestinal symptoms some individuals experience during or after an exercise. It is characterised by nausea, bloating, cramping, diarrhoea, pain, and vomiting.

Runners with sensitive stomachs are particularly prone to these occasional GI flare-ups. The good news is that runner’s gut problems are often preventable. But what are the triggers of this digestive tract disorder in runners? Let’s find out!

Group of people are running for marathon HIGH5 section image

What Causes Stomach Pains When Running?

Lower abdominal pain while running, or exercise-induced gastrointestinal syndrome, can be caused by a combination of factors, including the following:

1. Physical Jostling

Physical jostling from the repetitive running motion can contribute to the runner’s stomach symptoms. The constant bouncing can trigger peristalsis—involuntary contraction and relaxation of the digestive tract muscles—leading to an urgent need for a bowel movement or diarrhoea. This effect is particularly noticeable during long runs or intense training sessions.

2. Blood Flow Redistribution

During strenuous exercise, there’s a redirection of blood flow away from your digestive tract and towards your muscles, heart, and lungs. This reduced blood flow to the GI tract can cause stomach pain when running.

3. Pre-Exercise Meals

Not leaving enough time between eating and running can be one of the causes of runner’s stomach pain. Also, consuming certain foods before a run, notably those high in fibre, fat, or sugar, can cause you to experience stomach pain. Check out our guide on what to eat before a run for proper dietary recommendations.

4. Hyperactivity

Pushing yourself too hard during a race can increase the risk of experiencing runner’s tummy. That’s because intense physical exertion diverts blood flow away from the digestive system, impairing digestion and leading to discomfort. Additionally, pushing the body to its limits can result in dehydration symptoms, further exacerbating gastrointestinal issues.

5. Dehydration

Insufficient fluid intake before or during a run can affect digestion and lead to gastrointestinal distress. In moments where you experience dehydration, it’s important to know how to rehydrate fast with water and hydration/electrolyte drinks.

6. Stress and Anxiety

Emotional stress and anxiety can exacerbate the symptoms of runner’s tummy. The body’s response to psychological stress can disrupt the normal functioning of the digestive system, leading to runner’s stomach symptoms.

7. Running When Hungry

Not fueling up and running when hungry can contribute to runner’s tummy. When you don’t provide your body with enough fuel before a run, it can lead to low blood sugar levels and inadequate energy for proper metabolism.

8. Menstrual Cycle

The menstrual cycle is one of the causes of runner’s tummy in females. Hormonal fluctuations during that time of the month can lead to stomach upset, cramps, and other gastrointestinal discomfort. These symptoms can be exacerbated during running, causing discomfort and distress.

9. Increased Intestinal Transit

Exercise can increase the speed at which food moves through your intestines, i.e., peristalsis. This rapid transit can lead to loose stools or irritable bowel syndrome, a common symptom of runner’s stomach pain. The body doesn’t have enough time to absorb water from the waste, resulting in more frequent, watery bowel movements.

10. GI Issues

GI tract distress, like acid reflux, is a prime contributor to runner’s stomach pain. Digestive distress results from the body directing blood flow away from the digestive system during strenuous exercise, such as running.

Now that you know the several triggers of stomach pain when running, it’s equally important to understand actions to take to prevent it from happening, as well as management options.

How to Prevent Running Stomach Pains and Diarrhoea

Lower abdominal pain while running is no joke and can ruin your workout. However, there are some activities you can incorporate into your lifestyle to prevent or manage stomach pain or GI symptoms, including:

  • Healthy nutrition
  • Staying hydrated
  • Probiotics for a healthy digestive tract
  • Starting your run slowly

Here is a detailed breakdown of each option:

1. Healthy Nutrition

First, watch what you eat before a run. Avoid high-fibre, greasy, or very sugary foods, which can be harder to digest. Stick to sports nutrition or easily digested carbs like rice, bananas, and toast.

We also recommend avoiding supplements, gels and chews with artificial colours or sweeteners, as they can irritate your stomach. Healthier options like HIGH5 Energy Gels with natural and enriching ingredients are the way to go.

Tip: If you’re running longer distances, check out our marathon nutrition plan for additional dietary recommendations.

HIGH5 Energy Gels

2. Staying Hydrated

Hydrate appropriately in the days leading up to your run. Dehydration is a common cause of diarrhoea and stomach cramps after running. Drink plenty of water and electrolyte drinks to ensure you’re well-hydrated before hitting the road or trail.

3. Probiotics for a Healthy Digestive Tract

Your gut health has a significant impact on how well you can tolerate exercise. Probiotic supplements help maintain the healthy bacteria in your digestive tract that aid digestion and boost immunity.

Take a probiotic capsule a few times a week, especially in the days leading up to a long run. This helps ensure your stomach can handle the additional nutrition and hydration needs. It’ll also keep digestive symptoms at bay.

4. Starting Your Run Slowly

Easing into your run allows your digestive system to gradually adjust to the movement and blood flow changes. On the contrary, sudden bursts of intense running can rapidly divert blood from your gut and stress your stomach.

By fueling smart, staying hydrated, and taking it slow, you can “prevent the runs from ruining your runs.” No one wants their workout cut short, so take steps now to keep your stomach happy and your runs diarrhoea-free.

The above tips only help you prevent runner’s tummy from occuring. So, how do you manage this GI issue when it occurs in the middle of a run? Continue reading to find out!

Get Rid of a Sharp Pain HIGH5 section image

How Do You Get Rid of a Sharp Pain in Your Stomach When Running?

If you have stomach pains while running, you can manage the situation by trying the following runner’s stomach cure options:

  • Stop the race.
  • Choose your energy gels carefully.

Let’s explore each option to better understand how to stop stomach pain while running.

1. Stop the race.

In a case where you experience tummy issues mid-run, slow down and breathe steadily through your nose to relax. After that, do the following:

  • Drink water or an oral rehydration solution made by dissolving HIGH5 Hydration Tablets in water to replace fluids and electrolytes lost from diarrhoea.
  • Rest for a few minutes before slowly starting up your run again.
  • Don’t try to power through — that will only make things worse.
  • Gently massage your abdomen to relieve gas and cramps.
  • Walking for a few minutes can also help.

2. Take energy gels.

High5 Energy Gels

While taking too much of the wrong gels and supplements can trigger a stomach upset, they can be beneficial when taken in the right amounts. Most importantly, it’s important to opt for brands that use simple and healthy ingredients that are easy to digest. This means avoiding products with artificial sweeteners and excess sugar alcohols that can irritate the stomach.

For example, HIGH5 Energy Gels come in flavours like orange, mango, apple, etc, and have a mild, natural sweetness without the sugary aftertaste of artificial gels. These gels are easily digestible and scientifically formulated multi-carbohydrate energy gels with no nasty additives.

Start with just half a gel to see how your system tolerates it before gradually increasing it. It also helps to take gels with water to aid absorption and avoid concentration in the gut. For distance runners who are unsure about the right gel amount, check out our guide, which discusses how many gels a marathon runner needs.

Tip: Remember to sip some fluid as you go to maintain hydration. Also, watch what you eat in the hours leading up to your run.

HIGH5 ZERO electrolyte tablet

Frequently Asked Questions

When should I be worried about stomach pain?

You should be worried if you’re consistently experiencing stomach pains when running despite taking preventive measures. If you experience any severe runner’s stomach symptoms alongside your stomach pain, it’s essential to seek immediate medical treatment. You’re likely dealing with a more serious digestive issue beyond the typical discomfort of runner’s belly.

These symptoms may include:

  • Long periods of diarrhoea
  • Severe heart palpitations
  • Loss of consciousness
  • Sudden acute headaches
  • The presence of bloody or black stool

How long does runner’s stomach last?

Runner’s stomach usually kicks in around 15 minutes into your exercise session and could last for some hours after, but never more than 24 hours. However, if the loose bowel movements and gastrointestinal complaints continue beyond this timeframe, it may indicate an underlying medical condition that requires further evaluation.

Why does my stomach hurt when I run?

Your stomach may hurt when you run because exercise results in a redirection of blood away from the gut and towards the flexed muscles. Having a meal right before a workout session doesn’t allow for proper digestion, triggering gastrointestinal discomfort.

Another factor that can contribute to stomach cramps after running is dehydration and low electrolyte levels. To alleviate this discomfort, it’s important to stay adequately hydrated by drinking enough water and hydration formulas before and after your workout.

What are 4 signs and symptoms of gastroenteritis?

Gastroenteritis is a common condition marked by inflammation, irritation, and infection of the stomach lining and intestines.

Four common signs and symptoms of gastroenteritis include:

  1. Diarrhoea: This is a hallmark symptom of gastroenteritis and can be pretty severe.
  2. Vomiting: Along with diarrhoea, vomiting is another common symptom, as your body attempts to eliminate the agent causing the inflammation.
  3. Nausea and stomach pain: Before vomiting, you may experience a general feeling of being unwell with an upset stomach.
  4. Abdominal pain and cramps: The inflammation of the stomach and intestines can lead to discomfort and runner’s stomach pain in the abdominal area.

There are other symptoms of gastroenteritis aside from the 4 listed above, including low-grade fever, headache, and muscle aches. If you experience persistent symptoms despite adopting management options, you should seek medical attention immediately.


Experiencing stomach pains when running shouldn’t steal the joy of your run. Knowing the causes and effective management and prevention options empowers you to confront this hurdle head-on. No more emergency stops or cutting your weekend long runs short — incorporate the right electrolyte drinks and energy gels into your workout sessions to reduce the occurrence of devastating stomach pains during your runs!

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