How to Eat During Long Runs

I’ve run two half-marathons, and now I’m training for my first full marathon. I log a long run—anywhere from 15 to 30 kilometres—every Sunday. But I run out of steam almost every time, even though I drink water and Gatorade while I run. Should I eat during the run too? —Jenny

Dear Jenny,

First of all, congratulations on making the jump to the full marathon! On the day you finish, you will be a member of a courageous and distinct club!

I remember my first marathon all too well, and when I think about my fueling plan (I didn’t have one) and how hard I hit the wall (early and often), I realize that I ran on empty, which led to a slow finish time and painful memories. But don’t worry—you have time to learn how to fuel on the run, even for one that’s 42 kilometres long.

During your half-marathons, you may not have used any fuel. Some runners don’t—they may not know they need to, or they may rely on the sports drink at the aid stations to hydrate and fuel them along. The latter method can help a runner crank out a decent finish, but even a half-marathoner might be surprised at the improved finish time and overall experience if they were to add in a little bit of what I call “high-octane fuel.”

High-octane fuel is essentially more concentrated; it’s the energy gels, blocks, beans, and chews you may have seen some long-distance runners carrying as they set out for a long run. These sports nutrition products are engineered to supply badly needed carbohydrate, which fuels your muscles and keeps blood sugar levels steady, and electrolytes, which help retain fluids to maintain hydration, prevent cramping, and perform a host of other functions in the body.

You can find high-octane fuel at your local supermarket, sporting goods store, running store, or online. There are many different options and in a future post, I’ll review them. But for now, I would recommend you ask training buddies what they use or simply go shopping, pick up a few different brands and types (gels, chews, etc.), and try one during your next run. Or, check with the race to see what brand and flavor they will provide on race day. If you train with the same brand and flavour that will be handed out on the course, you’ll eliminate the need to carry a lot of fuel with you. But we’ll get to that in a future post!

For now, I’d like you to start simply adding in at least some high-octane fuel as you run long. Start slow; you need to train your gut (and your palate) to handle fuel on the run.

In general, runners need to add in 30 to 60 grams of carbohydrate each hour that they are running longer than 75 minutes. But you’ll need to start fuelling earlier than 75 minutes into a run; by that time, your tank will be empty, and once you hit empty it is very hard to recover. Start taking in fuel within 30 minutes of hitting the pavement.

I personally take a little bit of fuel every 15 minutes. I’ve found that this method keeps my energy levels steady, and I don’t get any GI distress. Some runners find that when they add in too much fuel—like an entire gel at one time—their digestive system is upset. Since you are new to fueling on the run, eat maybe half a gel or a few blocks or a few beans every 15 minutes.

Be sure to follow your high-octane fuel with water. Your stomach can only tolerate a certain percentage of carbohydrate so you need to dilute your fuel in order for it to go into circulation (rather than sit like a stone in your gut!).

As you try out fuel during your training runs, keep track of how much you took in and how your body responded. Keep track of answers to questions like: Did you feel totally energised? Were you able to keep your pace constant but then hit the wall towards the end of a run? Did your stomach not agree with the fuel?

The answers to these questions will help you form your race-day fuelling plan. The answers will help you learn whether you have the perfect fuelling plan in place, need to add in more fuel towards the end of a run, or try a different brand/type of fuel, respectively.

Jenny, I hope this introduction to fueling on the run helps your runs go a little smoother. Stay tuned to learn more about what brands to try, exactly how much fuel to consume, alternate fueling options, and to learn about how much fluid to drink while you are running long.

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