You may be asking, why do I feel nauseous after running? You’re not alone. Many runners like you also experience it during or following exercise. While uncomfortable, nausea and vomiting after running is rarely a cause for serious concern.

In most cases, nausea is simply your body’s signaling that something is off. So, understanding the common causes can help you identify triggers and take steps to prevent this post-run queasiness.

In this article, we’ll explore the (physiological and psychological) factors that can lead to nausea and provide practical strategies to address them.

Common Causes of Nausea After Running

Several potential culprits are behind runners’ nausea. Some are physiological, while others are psychological factors. Whichever the case, they can ruin your day after running. 

Here’s a comprehensive list of the most common ones:

1. Dehydration

Dehydration, especially on hot days, can quickly lead to nausea during a race. Running causes significant fluid and electrolyte loss through sweating. If not replenished with adequate water and sports drinks, this loss can result in dehydration.

Dehydration reduces blood volume, leading to decreased blood flow to the stomach and intestines. This heightened sensitivity of the nerves in these areas can trigger nausea and vomiting. 

Additionally, the drop in electrolytes, such as sodium and potassium, can disrupt signals between the brain, stomach, and intestines, further contributing to feelings of nausea.

2. Heat exhaustion/heat stroke

When you run in hot and humid weather, your body has to work much harder to regulate your temperature through sweating. The high heat and humidity combo makes it difficult for sweat to evaporate off your skin and properly cool you down.

As your core body temperature rises, your heart rate increases to pump more blood to your skin to dissipate heat. However, this increased demand on your cardiovascular system can only compensate for so much.

If your body temperature keeps climbing to dangerous levels, you may develop heat exhaustion or potentially heat stroke. Both of these conditions cause nausea, dizziness, headache, and vomiting.

3. Hypoglycemia

An extended running period makes your muscles rapidly use glucose from your bloodstream for energy. If you don’t adequately replenish glucose via snacks or carb-loading, your blood sugar levels can drop too low.

This is called hypoglycemia. It leads to symptoms like nausea, dizziness, fatigue, shakiness, and abdominal pain after running. This is because your brain relies on steady glucose from the blood to function properly. As a result, low blood sugar impairs brain function and triggers nausea signals.

4. GI Distress

During exercise, blood flow is redirected from the digestive system to the working muscles. This can decrease intestinal blood flow, resulting in decreased oxygen and nutrient availability for normal gastrointestinal functions. Ultimately, you may exhibit nausea symptoms, which hurts your stomach after running. 

5. Heartburn

The up-and-down impact of running combined with a full stomach can worsen heartburn and GERD symptoms. Stomach acid splashes into the esophagus, creating a burning sensation in the chest and throat.

This irritation and inflammation also trigger nausea signals to your brain.  Moreover, pre-run foods like high fat, fiber, protein, beverages, and dairy may trigger nausea or indigestion before high-intensity exercise.

6. Psychological  Factors

Psychological factors play a significant role in influencing how our bodies respond to physical activities like running. In the context of post-running nausea, several psychological elements can contribute to or exacerbate this discomfort. 

Here are some:

How to Address Nausea After Running

interval running

Now that you know what typically triggers a runner’s nausea, let’s explore some simple strategies to prevent and manage it.

Here’s how to prevent throwing up while running:

1. Hydration and Nutrition Strategies

2. Good Breathing Techniques

Breathing properly can help you regulate your oxygen and carbon dioxide levels, which can affect your blood pH and nausea. It can also help you relax your mind and body to reduce anxiety and running sickness.

Here are some good breathing techniques to help manage stomach hurts after running:

Depending on your needs and preferences, you can practice these breathing exercises before, during, or after your run. 

3. Gradually Cooling Down

Abruptly stopping after sustained exertion causes blood to pool in your lower limbs rather than return to your GI tract. This triggers nausea. 

Here are some tips on gradually cooling down after a run to prevent nausea:

4. Identify Personal Triggers

Everyone is different, and what causes nausea for one person may not affect another. By identifying your specific triggers, you can avoid or modify them to reduce your risk of nausea.

Here are some ways you can identify your triggers:

5. Seek Professional Advice

Finally, if your nausea is persistent, severe, or accompanied by other symptoms, such as chest pain, shortness of breath, or fainting, you should seek professional advice. 

Nausea after running can sometimes indicate an underlying medical condition, such as:

For most runners, implementing the tips above will help tame an unruly tummy. But don’t hesitate to get medical guidance for persistent nausea that interferes with your running.

Final Thoughts

Feeling nauseous after a run can be frustrating, but it’s usually not a big concern. Even experienced runners deal with upset stomachs from time to time. Things like not drinking enough water, not eating well, breathing weirdly, pushing yourself too hard, or feeling stressed can make it more likely to happen.

But don’t worry! Following the tips mentioned earlier and making a little effort, you can avoid that yucky feeling after your run. Pay attention to when you start feeling bad and change your routine if needed. 

Stay positive; with a few simple tricks, you’ll be running comfortably in no time!