Nutrition Diet: Do running gels give you a stitch?

October 3, 2025 •

5 min read

Up to 70% of runners experience exercise-related abdominal pain, but do running gels give you a stitch? While not the sole cause, concentrated sugars and improper hydration practices surrounding their use are often significant contributing factors. Successfully fueling for your race or long run depends on understanding your body's specific needs and developing a strategy that avoids gastrointestinal distress.

Quick Summary

Running gels are not a direct cause of side stitches, but their high sugar concentration can trigger gastrointestinal discomfort without proper hydration. Factors like gut sensitivity, insufficient water intake, gel type, and lack of gut training increase the risk of cramps and bloating during a run.

Key Points

Not a Direct Cause: Running gels are not the sole cause of side stitches, but poor consumption habits or a sensitive stomach can trigger them.
Concentrated Carbs: Traditional gels are high in concentrated carbohydrates, which require adequate water to be digested properly and prevent cramping.
Hydration is Key: Always take gels with water to aid absorption. Inconsistent hydration or consuming gels with sugary drinks increases GI distress risk.
Gut Training: Practice your fueling strategy during training runs to acclimate your digestive system to processing carbohydrates under stress.
Choose Your Gel Wisely: Isotonic or hydrogel options can be gentler on sensitive stomachs, as they are formulated for easier absorption.
Mind Your Breathing: Shallow breathing can cause diaphragmatic cramps. Focus on deep, controlled breathing to prevent stitches.
Strengthen Your Core: A stronger core can help stabilize your torso and ligaments, reducing the strain that can contribute to side stitches.

The Surprising Science Behind the Side Stitch

That sharp, nagging pain in your side, known as an exercise-related transient abdominal pain (ETAP), has puzzled athletes and scientists for years. While the exact cause remains elusive, a leading theory suggests it's related to irritation of the parietal peritoneum—the membrane lining your abdominal cavity. Running's repetitive jostling and increased demand on the diaphragm muscle can cause this irritation, and this is where nutrition comes into play. The concentrated carbohydrates in running gels, when not properly consumed, can exacerbate this issue, leading many to mistakenly blame the gel itself for the problem.

Why Running Gels Can Trigger GI Issues

During intense exercise, your body prioritizes sending blood to your working muscles and respiratory system, diverting it away from your digestive organs. This makes digesting anything during a run a challenging task. When you consume a traditional running gel—which is essentially a highly concentrated dose of carbohydrates—your body needs water to help dilute and absorb the sugars. If you don't drink enough water with the gel, your digestive system will pull water from other parts of your body to aid digestion, which can cause bloating, cramping, and, in some cases, diarrhea. This digestive distress adds to the overall abdominal strain, potentially triggering or worsening a side stitch.

The Role of Carbohydrate Concentration and Type

Concentration: The osmotic pressure created by a highly concentrated sugar solution in your stomach is a primary culprit for gastrointestinal (GI) issues. Your body works to balance the concentration, which involves drawing fluids and can slow down gastric emptying, leading to discomfort.
Carbohydrate Type: Many traditional gels use simple sugars like maltodextrin and fructose. Some individuals, particularly those with sensitive guts, may have trouble absorbing high amounts of fructose, which can cause gas, bloating, and cramping as it ferments in the large intestine. Opting for gels with a dual-carbohydrate blend (e.g., glucose and fructose) can use different intestinal transporters and improve absorption.

Other Causes of Side Stitches

Beyond nutrition, several other factors contribute to the risk of experiencing a side stitch during a run. Addressing these can significantly improve your comfort:

Breathing Technique: Shallow, rapid breathing can restrict blood flow to the diaphragm, causing it to cramp. Focusing on deep, diaphragmatic breathing helps ensure the muscle receives adequate oxygen.
Weak Core Muscles: A strong core provides better stability for your torso and abdominal organs while running. Weakness in this area can lead to extra strain on the ligaments connecting your internal organs to the diaphragm, potentially triggering a stitch.
Poor Hydration: While over-hydrating right before a run can be a problem, so can dehydration. Proper hydration throughout the day is key to preventing muscle cramps.
Running Intensity: Pushing too hard, too fast can strain your respiratory and core muscles, increasing the likelihood of a stitch. A proper warm-up and gradual increase in intensity are crucial.
Eating Too Close to a Run: Eating a large, heavy meal (especially one high in fat and fiber) within 1-2 hours of a run diverts blood flow to the stomach for digestion, away from the diaphragm, increasing stitch risk.

Choosing the Right Gel: A Comparison Table

Not all gels are created equal. The market offers various formulations designed to address different needs and sensitivities. Here is a comparison to help you choose what might be best for your gut:


Feature	Classic Energy Gels	Isotonic Energy Gels	Hydrogel Gels
Carbohydrate Concentration	High	Lower (pre-diluted)	High (encapsulated)
Water Requirement	MUST be taken with water for proper digestion	Can be taken without additional water	Typically taken without additional water, but hydration is still critical
Absorption Mechanism	Relies on water from the body; can be slower and cause GI upset if not enough fluid is consumed	Pre-mixed for faster gastric emptying; lower risk of GI issues from concentration	Encapsulates carbs in a hydrogel, which is designed to bypass the stomach and improve GI tolerance
Typical Ingredients	Maltodextrin, fructose, water	Maltodextrin, water, electrolytes	Alginate and pectin from natural sources to form a hydrogel matrix
Texture	Thicker, syrupy	Thinner, more fluid	Thicker, more like a firm gel/Jell-O
Best For	Experienced runners who know their fueling strategy and stomach tolerance	Sensitive stomachs or when carrying extra water is not an option	High-carb fueling for endurance athletes with sensitive stomachs

Strategies for Avoiding Gel-Induced Stitches

If you find that gels are an important part of your fueling strategy, there are several ways to minimize the risk of stomach issues:

Practice 'Gut Training': Just like your muscles, your digestive system can be trained. Practice your race-day fueling strategy during long training runs to teach your gut to process a higher load of carbohydrates and fluid under stress. Starting with smaller amounts and gradually increasing intake over weeks can improve your tolerance.
Stay Hydrated Consistently: Don't rely on just the water you take with your gel. Hydrate well in the 12 hours leading up to a run and sip regularly throughout the effort, especially in warm weather.
Time Your Intake: Don't wait until you're exhausted to start fueling. Begin taking gels early in your run (e.g., around the 45-minute mark) and continue at regular intervals (every 30-45 minutes). This prevents sudden carb intake and keeps energy levels steady.
Sip, Don't Gulp: When taking a gel, consume it slowly over a few minutes rather than all at once. This prevents a sudden flood of sugar and fluid into the stomach.
Test Different Products: Trial and error is key. Experiment with different gel brands and types (like those mentioned in the table) during training to find what works best for your body.

Conclusion: Finding the Right Fuel for Your Body

So, do running gels give you a stitch? The definitive answer is that they can, but only if they are not used correctly or if they are not the right product for your body's unique digestive system. It is a confluence of factors, including the gel's concentration, your hydration levels, breathing technique, and gut sensitivity, that truly determines your risk. The good news is that with a little pre-run planning and practice, you can easily avoid the dreaded side stitch. By training your gut, staying consistently hydrated, and finding a product that works for you, you can focus on your performance without worrying about stomach cramps or digestive distress.

For more information on nutrition for endurance athletes, you can consult resources like Runner's World.

Frequently Asked Questions

Side stitches can occur after taking a running gel primarily due to the high concentration of carbohydrates. If not consumed with enough water, the digestive system pulls water from the body to aid absorption, causing cramping, bloating, and irritation of the abdominal lining.

The best way to take a gel is to consume it with water, not another sports drink, to prevent an excessive sugar load. Sip it slowly over a few minutes rather than taking it all at once, and practice your fueling strategy during training to condition your stomach.

Gut training involves gradually introducing carbohydrates and fluids during training runs to help your digestive system adapt. This practice improves gastric emptying, enhances nutrient absorption, and reduces GI distress on race day.

Yes, isotonic and hydrogel formulas are designed to be gentler on the stomach. Isotonic gels contain added water for faster absorption, while hydrogels encapsulate carbohydrates to minimize GI irritation.

Besides gels, common causes of side stitches include improper breathing, weak core muscles, inadequate warm-up, and exercising too soon after eating heavy meals. Fatigue and hydration levels also play a significant role.

Keep a food diary during your training and note when you experience GI symptoms. Some ingredients, like high fructose concentrations or artificial sweeteners, can be common culprits for sensitive individuals. Switching to a lower-fructose or natural-ingredient gel might help.

You don't necessarily have to stop using gels. Try alternative fueling strategies first, such as switching to an isotonic or hydrogel, practicing gut training, and ensuring proper hydration. If problems persist, explore other fuel sources like chews, bars, or real food.