Some runners look forward to slurping down a caffeinated mocha gel at mile 15 of a long run. Others simply dread it.
Depending on the day, I have been both of those runners.
But regardless of how I’m feeling about it in the moment, that gel’s going down the hatch. Because the research is clear: Runners perform better when they’re fueling their workouts, especially long runs during marathon training.
Fueling on the run requires practice, and usually more trial and error than some runners expect. But once you nail it down, it pays off big on race day in the form of avoiding the wall and maintaining your pace through the end of the race.
“It’s so important to practice your fueling strategy during training so that once you get to race day, all you have to think about is racing,” Jordan Hill, RD, CSSD, a Colorado-based registered dietitian and certified specialist in sports dietetics with Top Nutrition Coaching, previously told Runner’s World.
Truthfully, swallowing a lukewarm, sweaty gel during a humid summer run never gets easier—you just get better at it. And as you fine-tune the number and timing of the gels you take in on your runs, you’ll get more confident doing it on race day.
To help you fearlessly knock down those gels throughout training, we’ve pulled together four top tips from our own experience and from talking to the experts.
Find Your Go-To Brand, Flavor, and Caffeine Content
Arguably the running gel pioneer of the 1990s, GU remains a household name among runners. But a near limitless selection of gels, chews, bites, and beans have followed in its wake. The key is to determine which brand’s formula and consistency feel best for your stomach, and then fine-tune the caffeine content you need, and the flavor you actually enjoy.
Many brands only offer certain flavors in caffeinated versions, so it’s important to confirm whether you’re signing up for standard strawberry or its mega-jolt cousin in the same flavor. Caffeine levels vary from brand to brand as well, so if you like a little extra energy kick, make sure you know how much you’re getting in each gel. Even small amounts of caffeine can cause GI distress for some runners.
Kristy Baumann, RD, LD, a Minnesota-based registered dietitian who works with runners, recommends visiting your local running store and seeing what samples they have available so you can try different options. I typically shop at The Feed, where you can pick and choose single-serve gels and chews from various brands, and build your own personalized variety box.
Test Your Gels at Your Own Pace
Hill says she always suggests testing one specific brand of gel at a time. This makes it much easier to determine which ones sit best in your stomach, compared to trying several brands during a single run.
Hill also recommends testing your gels on an easy run first, so you can focus on fueling logistics: How easily can you tear open the packet? Can you get it down in one gulp or do you need several small sips? Will you need to slow your pace or stop to walk to consume the gel? Doing this during an easy effort eliminates the stress of perfectly nailing splits or chasing pace targets.
If you’re completely new to fueling on the run, you don’t even need to commit to a whole gel at once. Start with just half a gel and see how you feel. Then, you can determine how frequently you want to take those gels (or half-gels). Baumann previously told Runner’s World that every 45 minutes is a good place to start for many runners.
The final step in nailing your fueling plan is gradually increasing the number of gels you take and how frequently you take them until you meet your fueling needs. This varies from runner to runner, but most recommendations fall in the range of 30 to 90 grams of carbs per hour. If that sounds like a lot, just remember that there was a time when your daily easy run once felt like a long run. “Our stomach is a muscle and it can be trained, just like we train our legs to keep running,” Baumann says.
Wash It Down With Water
As a runner who doesn’t always carry water on runs, I wanted to make sure my fueling strategy wasn’t tied to my access to water stops. For that reason, I like isotonic gels, because you don’t need to take them with water.
Isotonic means these gels are slightly diluted to match the concentration of fluids in your bloodstream and digestive tract, which helps alleviate GI distress. Some top brands that offer isotonic gels include Maurten, SiS, Amacx, and UCan.
If you’re using other brands, like Honey Stinger or Huma, make sure you have fluids on hand. You don’t need to gulp down a lot—two to four sips of water is usually enough for one gel, says Hill.
Log Your Miles … Then Log Your Fuel
After every fueling session, keep track of what worked and what didn’t. You can jot these notes down wherever you log your daily miles. Hill recommends tracking details like brand and flavor, the amount you consumed, how frequently you fueled, and how you felt overall. This way, you’ll have all the data you need to make adjustments.
For example, if you look back at your notes and read, “Woof. Bonked at mile 10,” you may need to increase the amount of carbs you’re taking in each hour, or you may need to start fueling earlier in your run. Notes like, “felt nauseous and sloshy” can mean you need to consume less gel at one time, but increase the frequency at which you take them.
And last but not least, reminders in your log like, “Couldn’t get this down no matter how hard I tried” might mean you need to switch to a different brand, consistency, or flavor.
Figuring all of this out in training means, come race day, you’ll know exactly what gels to carry, how many, and the checkpoints at which to take them. And that just might be the difference between breaking down at mile 20—or speeding up!
Morgan is a gear editor who has been with Runner’s World since 2017. She started as an intern ghostwriting The Warmup, a bygone version of the daily RW newsletter. Now, she tests and reviews anything you might find on runners’ feet-from crew socks and compression boots to carbon-plated super shoes.
A lifelong runner and shoe geek, Morgan has been chasing the perfect pair of kicks since she joined her grade school cross-country team. Since then, she ran as a Division I walk-on for the cross-country and track & field teams at the University of Delaware, where she studied English and Biology. She has one full marathon under her belt, and has raced more halfs and 5Ks than she can count.