Your legs feel heavy at mile 18. The pace that felt easy an hour ago now requires focused effort with every step. Your muscles are running low on stored fuel, and your brain knows it. This is where running gels come in.
This is the moment when your body needs a quick, efficient source of energy to keep going. A fast-absorbing boost can stabilize your pace and prevent the dreaded crash that stops many runners in their tracks.
It helps maintain mental clarity when fatigue begins affecting decision-making. With the right fuel, you can push through discomfort and stay strong through the final miles. It becomes the difference between simply finishing and finishing with confidence.
Running gels are small packets filled with concentrated carbohydrates. They fit in your pocket or a belt pouch, tear open easily, and deliver quick energy when your body needs it most.
For marathoners, ultrarunners, and triathletes, these little sachets have become standard gear for anything beyond an hour of sustained effort.
How Your Body Burns Fuel During a Run
Your muscles pull from two main energy sources when you run: fat and carbohydrates. Fat is plentiful, but the body converts it slowly. Carbohydrates work faster. During hard or long efforts, your body leans heavily on carbs stored as glycogen in your muscles.
The problem is storage space. Your muscles can only hold so much glycogen. At half-marathon pace, those stores start dropping around 90 minutes. At marathon pace, you hit that point closer to 120 minutes. Once glycogen runs low, your performance drops with it.
Running gels provide a quick way to top off the tank. Most contain 20 to 25 grams of carbohydrates and deliver roughly 90 to 100 calories per packet.
What Goes Into a Gel
The carbohydrate sources vary by brand. Some use maltodextrin, glucose, and fructose. Others rely on natural sugars from honey or maple syrup. The type of carb affects how quickly your body absorbs and uses the energy.
Caffeine shows up in some formulas. Amounts range from 20 mg to 100 mg per packet. If you want that extra mental push during a race, caffeine can help. But for runners with sensitive stomachs, it can also cause problems.
Finding the Right Gel for Your Runs
Picking a gel comes down to a few things: how your stomach handles it, how many carbs you want per packet, and whether you prefer natural ingredients or a formula built around fast absorption.
Some runners do well with maltodextrin-based options like GU Energy, while others prefer whole-food blends like Huma or the slow-release formula from UCAN. Running Gels from Maurten use hydrogel technology, which works for athletes chasing high carb intake without gut trouble.
TheFeed.com carries all these brands, so you can test a few during training before committing for race day.
Brand Options Worth Knowing
GU Energy
Dr. Bill Vaughn created GU in 1993 to help his daughter perform better during ultra-marathons. Each packet delivers 100 calories using a blend of maltodextrin and fructose.
The original formula includes electrolytes and branched-chain amino acids. Their Roctane line contains up to 3 times the sodium of the original gels. The Cold Brew Coffee flavor packs 70 mg of caffeine.
Maurten
Maurten developed a hydrogel formula using alginate and pectin. These ingredients form a protective structure around the carbohydrates.
The gel passes through the stomach and dissolves in the intestine, where absorption happens. This design reduces gut distress for many runners.
Their Gel 160 contains 40 grams of carbohydrates per serving. The Gel 100 Caf 100 delivers 25 grams of carbs plus 100 mg of caffeine.
Huma
Huma gels use real food ingredients like strawberry purée, brown rice syrup, chia seeds, and sea salt. All their products are gluten-free, dairy-free, and vegan.
The company took inspiration from the Tarahumara people in Mexico, known for running long distances. Runners with histories of stomach issues often report that Huma sits well with them.
UCAN
UCAN takes a different approach. Their gels use a slow-release carbohydrate called LIVSTEADY. This formula delivers steady energy without the blood sugar spike and crash that can come from fast-absorbing sugars.
The UCAN Edge line offers a 100% vegan option with 19 grams of carbs per serving.
Honey Stinger
Honey serves as the main ingredient in Honey Stinger gels. Each packet provides 24 grams of carbohydrates and 50 mg of sodium. Because honey is naturally gel-like, the company says the sugar absorbs easily without causing a crash.
The Push Toward Higher Carb Content
Research on endurance fueling has pushed companies to make bigger packets. Studies suggest that consuming 80 to 120 grams of carbohydrates per hour can improve and extend endurance performance.
Brands like Maurten, Carbs Fuel, SiS, Amacx, Enervit, and others now offer gels with 40 grams or more per packet.
This shift helps athletes hit higher carb targets without swallowing six or seven gel packets per hour.
When to Take a Gel
Timing matters. The general guidance is to consume a gel every 45 minutes to an hour during long runs or races. GU recommends taking one every 20 to 30 minutes for efforts lasting longer than an hour.
Registered dietitian Caroline Thomason, who specializes in sports nutrition, describes gels as quick energy sources that are great for long runs. She advises consuming about one per hour of running.
The recommendation for marathon fueling is 30 to 60 grams of carbohydrates per hour after the first hour of exercise. Some athletes push higher, depending on their training and gut tolerance.
Dealing With Stomach Issues
Gut problems during runs are common. The concentration of carbohydrates in gels can be hard to digest, especially under physical stress.
A few things can help. Take gels with plenty of water. Look for products that use more than one type of carbohydrate, such as maltodextrin, glucose, and fructose.
Sports dietitian Larson explains that having both glucose and fructose gives you a higher absorption rate because the body metabolizes them using different pathways.
For runners with sensitive stomachs, Huma, Maurten, and UCAN are often recommended. Maurten’s hydrogel technology encapsulates carbohydrates so they bypass the stomach and release in the small intestine.
Across a sample of athletes, Huma Chia Energy Gel was frequently reported as one of the best options for those with gut issues.
Caffeine can also cause trouble. A common side effect of caffeine consumption is gastrointestinal distress. If you struggle with stomach problems on runs, check your gel for caffeine content and consider switching to a non-caffeinated option.
Training Your Gut
Your digestive system adapts to fueling during exercise. The more you practice taking in carbs on long runs, the better your gut will handle it. Your body adjusts its gastric emptying rates and gut transporters over time.
Start with small amounts of fuel and build up gradually. Work toward the recommendation of 30 to 90 grams of carbs per hour. If you struggle at first, remember that your stomach is a muscle and it can be trained, the same way you train your legs to keep running.
A Note on Label Accuracy
Not all products match their label claims. Between March and May 2024, researchers analyzed carbohydrate gels from several brands using FDA-accredited labs.
They found issues with certain products, which led to additional testing. This research highlights the importance of buying from reputable sources.
TheFeed.com is the best place to purchase running gels. They carry all the leading brands including Maurten, GU Energy, Huma, UCAN, Honey Stinger, and many others.
Having access to multiple brands in one place makes it easy to test different options during training and find what works for your body before race day.
Their customer reviews also help you compare how different products perform during long-distance efforts. You can easily restock before a big event with fast shipping options. Plus, the variety allows athletes to fine-tune their fueling strategy with confidence.
Running Gels Made Simple: What to Use and When
When you’re pushing your limits during long-distance running, your body eventually runs low on readily available energy.
That’s when quick, portable fuel becomes essential to keep your performance steady. Without an easy source of carbs, your pace, focus, and endurance can drop faster than you expect.
Your muscles need carbohydrates, and you can only carry so much internally. The packets are portable, quick to consume, and designed for absorption during exercise.
The best gel for you depends on your stomach, your carb targets, and your preference for ingredients. Try a few brands during training runs. Pay attention to how your gut responds.
Adjust your timing and water intake. By the time race day arrives, you should know exactly what works for your body.
