What Are Energy Gels? | Fuel For Endurance Athletes

When your muscles run low on glycogen around the 60-minute mark of a run, ride, or hike, an energy gel delivers a rapid hit of easily digestible carbohydrate to keep you moving. The Australian Sports Commission describes them as a highly concentrated carbohydrate source with a “honey consistency,” and most contain maltodextrin, fructose, or a blend of both. They come in small 1-ounce or 1.5-ounce sachets, according to the Cleveland Clinic, and are meant for adults, not children.

The Basics Of What They Provide

A typical sports gel supplies about 20–30 grams of carbohydrate and roughly 80–120 kcal per packet. Most have little to no fat, fiber, or protein, which is precisely why they digest so quickly. Your body can shuttle that carbohydrate into your bloodstream within minutes, giving you a fast fuel boost when your legs start to fade.

That speed makes them different from whole-food options like bananas or dates, which also work but can sit heavier in your stomach while you’re bouncing along a trail. Gels are engineered for one job: fast fuel with minimal digestive work.

How To Use Energy Gels During Exercise

Take one gel roughly every 30–45 minutes during exercise that lasts longer than 60 minutes, aiming for 30–60 grams of carbohydrate per hour total. That works out to one to two gels per hour for most athletes, depending on your size and effort level.

Here’s the practical sequence that works in real-world conditions:

• Tear the sachet open with the notch on the side, not the top.
• Take it with a few gulps of water if you can — some gels are easier to swallow with liquid.
• Consume the whole packet in one go; resealing a partially eaten gel is messy and unnecessary.
• Stay on your schedule. Waiting until you feel empty forces you to play catch-up.
• Keep a small trash pocket in your vest or jersey for the don’t litter on the course.

Some gels are formulated specifically to be taken without water. Those tend to be thinner in consistency. Others are thicker and go down noticeably easier with a sip of water. The Australian Sports Commission notes that consumption during the session is what matters most for endurance efforts of significant length.

Caffeine, Stomach Issues, And Other Caveats

Many gels include caffeine for an extra alertness boost. The German Federal Institute for Risk Assessment (BfR) states that healthy adults are not expected to experience health risks from up to 200 mg of caffeine in a single dose or 400 mg spread across the day. That guidance is about caffeine generally, not gels specifically, but it gives you a safe ceiling when you add a caffeinated gel to your pre-workout coffee.

The BfR also notes that energy drinks are not recommended for children or pregnant or breastfeeding women. Energy gels are intended for adults, and the Cleveland Clinic is explicit that they are not for kids. If you’re pregnant or nursing, it’s wise to treat gels with the same caution the BfR applies to energy drinks, and check with your healthcare provider about caffeine and carbohydrate supplements.

Stomach trouble is the most common complaint among gel users. Gel formulations vary widely, and the one your training partner swears by might not agree with you. The Cleveland Clinic notes that gels are meant for quick digestion, but your gut still has to adapt. Test your gel of choice in training — ideally during a long run or ride — well before race day. If you feel queasy, try a different brand or flavor, or experiment with taking water immediately after the gel.

For cyclists looking for products that have been vetted for training use, our roundup of energy gels for cycling that perform well on long rides breaks down the top options by caffeine content and carbohydrate ratio.

FAQs

Do energy gels go bad?

Yes. Most gels have a shelf life of 12 to 18 months, printed as an expiration date on the packet.

Are energy gels just sugar?

Sort of, but the type of sugar matters. Most gels use maltodextrin, a complex carbohydrate made of glucose chains, often blended with fructose. This combination absorbs through different intestinal pathways, which is why many modern gels advertise a 2:1 or similar maltodextrin-to-fructose ratio.

Can you drink water right after taking a gel?

Yes, and for most people it helps. Water dilutes the gel’s thickness and helps move it into your stomach and intestines faster. For gels that are not specifically formulated for water-free use, a few gulps of water right after can reduce the sticky-mouth feeling and lower the chance of stomach cramps.