The wheels usually come off a long run slowly. Your legs still turn over, but the pace starts drifting, your form gets scrappy, and even a flat route feels harder than it should. That is often the point where energy gels for long runs earn their place. Used well, they help you keep effort steady, protect your pace late on, and finish stronger instead of just surviving the last few kilometres.
Why energy gels matter on long runs
For shorter runs, most runners can get by on normal meals and a bit of water. Once your run stretches beyond roughly 75 to 90 minutes, fuelling starts to matter a lot more. Your body stores carbohydrate as glycogen, but those stores are limited. If you run long enough without topping them up, you start to feel the drop in energy that runners know all too well.
That is where gels come in. They give you a quick, portable source of carbohydrate that is easy to carry and simple to take on the move. For runners training for a half marathon, marathon, or long weekend mileage block, they are often the most practical option. You do not need to stop and chew, and you can plan your intake with far more consistency than hoping a sports drink station appears at the right time.
The key point is that gels are not a magic fix. They work best when the rest of your setup is sound - decent pre-run meals, proper hydration, and a pace you can actually sustain. If your training is undercooked or you set off far too fast, no gel is going to rescue the day.
When to use energy gels for long runs
Not every long run needs the same fuelling approach. It depends on duration, intensity, weather, and your own tolerance. A relaxed 80-minute run after a good breakfast is different from a two-hour marathon session with pace work built in.
As a general rule, many runners start using gels when runs go beyond 90 minutes. If the session is harder, or if you are running first thing with limited breakfast, you may benefit from fuelling earlier. Marathon training is where gel use becomes less optional and more part of the job. If you plan to race with gels, you should practise with gels.
That point gets missed surprisingly often. Some runners save race fuelling for race day, then wonder why their stomach turns or why opening the packet feels awkward at pace. Long runs are your rehearsal. Use them to test flavour, timing, texture, and how much water you need alongside each gel.
How often should you take a gel?
Most runners do well taking a gel around every 30 to 45 minutes during a longer session, but there is no one-size-fits-all answer. The real target is carbohydrate intake per hour. Many runners sit comfortably around 30 to 60 grams per hour, while some experienced athletes can tolerate more, especially with mixed carbohydrate formulas.
If that sounds technical, keep it simple at first. Check the label. One gel may contain 20 grams of carbohydrate, another 25 grams, another more. Once you know that number, you can work out whether one gel every half hour or every 40 minutes makes sense for your session.
It is usually better to start before you feel empty. Waiting until you are already fading tends to mean you are chasing the run rather than supporting it. A practical plan for a two-hour run might be one gel at 35 to 40 minutes, another at around 75 to 80 minutes, and a third later if needed. For race-specific sessions, match the fuelling plan you intend to use on the day.
What to look for in an energy gel
The best gel is not always the sweetest, strongest, or most expensive. It is the one you can take consistently without upsetting your stomach.
Carbohydrate content is the first thing to check. You want enough fuel to make a difference, but not so much in one go that it sits heavily. Texture matters too. Some gels are thick and syrupy, while others are lighter or more liquid. If you struggle to swallow thick gels during harder efforts, a more fluid option can be easier.
Then there is the question of caffeine. Caffeinated gels can help with alertness and perceived effort, especially later in a long run or race, but they are not ideal for everyone. If you are sensitive to caffeine, taking one on an empty stomach or late in the day can backfire. It is useful, but it needs testing.
You should also check whether a gel is designed to be taken with water. Some products are more concentrated and feel much better when washed down properly. Others are built to go down more easily without as much fluid. Ignore that detail and you can end up with stomach cramps or a sticky mouth that puts you off taking the next one.
How to avoid stomach issues
The biggest mistake with gels is not the brand. It is poor timing and poor practice.
If you have ever taken a gel at high effort, with no water, in warm conditions, after skipping breakfast, and then blamed the gel, you are not alone. Stomach issues often come from the whole fuelling picture rather than one sachet.
Start by testing gels in training, not in races. Use them on easier long runs first, then on sessions that include marathon pace or progression work. Take small sips of water where recommended. Do not suddenly double your intake because a training mate says they take far more carbs per hour. Gut training is real, and it takes time.
Temperature can make a difference as well. In warmer weather, dehydration can make gels harder to tolerate. In colder weather, they can become thick and awkward to swallow if you have tucked them into a pocket for too long. Small details matter when you are trying to fuel on the move.
Gels, chews, or sports drinks?
Gels are popular because they are compact, fast, and easy to carry, but they are not the only option. Some runners prefer chews because they can take fuel in smaller bites. Others rely partly on sports drinks, especially in races where drink stations are frequent.
There is a trade-off with each option. Chews can be easier on the stomach for some, but they take more chewing and can be fiddly when breathing hard. Sports drinks help with hydration and carbohydrate together, but you have less control over exact intake. Gels are efficient and predictable, which is why so many distance runners build their plan around them.
For many runners, the best answer is a mix. You might use a sports drink before the run, water during the run, and gels as your main carbohydrate source. It depends on what the route allows and what your stomach accepts.
Race day starts in training
If you are building towards a half marathon or marathon, your long runs should help you sharpen more than fitness. They should also make your fuelling automatic. Know where you will carry your gels. Know how you will open them. Know whether you prefer one just before a climb, after settling into pace, or at regular watch alerts.
That confidence matters. The less thinking you need to do late in a race, the better. Good fuelling is part of good pacing. It keeps decision-making simple when fatigue is creeping in.
For runners browsing nutrition options, it is worth choosing a gel from a trusted performance brand and then giving it a fair test over a few sessions. One bad experience does not always mean the product is wrong for you. Sometimes the dosage, timing, or hydration just needs adjusting. McDermott's Sports Centre stocks sports nutrition for runners who want to train smarter and fuel like a pro.
A simple gel strategy for most runners
If you are new to fuelling, keep the plan straightforward. Eat a normal pre-run meal you know suits you. For runs over 90 minutes, take your first gel before the energy dip starts, usually around 30 to 40 minutes in. Continue at regular intervals based on the carbohydrate content and run duration. Drink water with the gel if the product recommends it, and make notes afterwards.
Those notes are useful. Did the gel go down easily? Did it sit well at marathon pace? Did the flavour become sickly by the second hour? Small reactions tell you a lot, and they help you fine-tune before race day.
Long runs are where confidence is built. When your fuelling plan works, the session feels steadier, the final miles feel more controlled, and you finish knowing you have trained both your legs and your race routine. That is the real value of getting gels right - not just more energy, but a better chance of running the second half as well as the first.
