Fueling Long Runs, the 7 Secrets of Eating While Running

Both new and experienced runners find fueling for long runs challenging. Yes, while the learning curve for a beginner runner is steeper, even runners with many miles on their feet can still struggle with properly fueling their long runs.

Runners often tend to put the most emphasis on training; training the lungs, heart, and muscles (and hopefully mind). But, it’s not uncommon to skimp on “training the gut,” or adequately fueling for those long runs (and races!). Unfortunately, it sometimes requires a runner to bonk, or really struggle during a run/race to realize they need to take the nutrition topic more seriously.

Plus, some runners hesitate to fuel during a long run out of concern their GI system may not tolerate it well. Whether it’s a side stitch, unwanted pit stops, cramping, or feeling bloated, none of these are what a runner wants on a run. Meaning, it’s a valid concern, but the proper pre-run fuel, and fueling during your long runs, can normally help you avoid just that.

Related topic: What to Eat Before a Run

Seven Secrets for Fueling Your Long Runs

1. MiX uP your carbs and sugars.

Do your best to avoid eating the same fuel for the duration of your long run. Using the same fuel is not an optimal plan; choosing from a variety of carbs (with a variety of sugars) is a better plan.

Why? Different fuel types (i.e. sports drinks, jelly beans, a banana) are broken down into one of three simple sugars: glucose, fructose or galactose. Each of these sugars has a different ‘transporter’ to get into the bloodstream. A variety of sugars then helps prevent these transporters from overload, and you are less likely to have GI problems.

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2. PRACTICE Your Fuel Strategy During Long Runs

Running a race without previously training your gut during your long run fuel is a bad idea. While not all those completing long runs are training for a race, many are. It’s important that your body learns to cope with the gels, gu’s, bananas, etc. (and how to transport them) to avoid diarrhea/distress on race day. Training with your ‘race-day’ carbs or fuel will increase those “transporters” so you feel better, perform better during your runs, and ultimately, your race.

3. Fiber is great, but NOT before or during a run.

While fiber is normally a welcome add to our diet, that is not the case for pre-run fuel, nor fuel during a run. Fiber essentially helps keep food in our stomach longer, and that is an unwelcome benefit while running. A stomach full of food can cause GI distress, and unwanted bathroom (or forest/shrub) pit-stops.

PLUS, once fiber-rich food makes its way into the small intestines, it is more likely to produce gas, and cramping. That definitely is NOT what anyone needs during a long run or race.

Remember that fiber rich foods are typically green, leafy vegetables, fruit (with the peel), whole grains, beans, lentils, nuts and seeds.

Bottom line, avoid fiber before and during your long runs. Just be sure to get your intake of fiber at other times

Related topic: Side Stitch, How to Eliminate It!

4. Ensure that you drink enough FLUIDS.

To succeed with fueling during long runs, and enhance running performance, runners must hydrate before the point of dehydration. If dehydration occurs, it becomes very difficult for the body to cope, and “catch up”.

Why does insufficient hydration lead to GI distress during a long run? When we run, blood flow to the GI/stomach is already reduced as more of it is diverted to hard-working heart, muscles and lungs. If a runner experiences dehydration, the situation worsens. Says Krista Austin, Ph.D.: “If you get dehydrated, you can’t eat because you need blood flow into the stomach to digest.”

Keep in mind also that the fluids you ingest also help “transport” those sugars into the bloodstream more quickly. Quicker transport equals more fuel for hard working muscles, and less GI upset.

More Secrets for Fueling Long Runs

5. Electrolytes – Don’t IGNORE Them!

You are likely familiar with the term electrolytes. There are electrolyte beverages (i.e. Gatorade, Tailwind) that contain electrolytes, and of course, sugar to fuel your runs. Electrolytes (most common are sodium and potassium) are minerals that help regulate the body’s water/fluid balance during the run. It’s important for these minerals to stay within a certain range to allow your muscles to retain sufficient water that’s critical for proper muscle function.

When we sweat, especially with longer bouts of exercise and warm weather, we lose those electrolytes. According to Nancy Clark, RD, runners can lose as much as 1-2K mg of sodium. As such your goal is to replace ~500 mg of sodium per hour.

Essentially, longer runs, and those in warm weather will require electrolyte focus! But, for those shorter workouts in cooler weather, it may be okay to skip (or lessen the amount).

It’s important to check the gels, sports drinks, chews, etc. that you’re fueling with to assess the electrolyte content. It may be insufficient, and is wise to supplement with something like SaltStick, salt packets, or other products that have a higher electrolyte/sodium content.

6. Your Fuel for the Long Run: EARLY and OFTEN

If you wait until you feel like you need some fuel, it’s too late. This is a common mistake with fueling on long runs/in races; one which I have personally done as well. When your body is sending hunger or fatigue signals, it is often too late to make up for the lost energy.

A recommendation is to start fueling during the run within the first 30-45 minutes, and continue every 15-45 minutes thereafter. Smaller time increments are wise as the portion can be smaller, and your body will more easily absorb/use the sugars if you have a small amount in your stomach from the beginning.

Many sources, such as Runner’s World, recommend anywhere from 30-60 grams of carbohydrates per hour during a long run or race (75 minutes plus). The range is wide, and partially is driven by your weight, the duration of your run, the weather, etc. Plus, how much the gut has been trained leading up to the race.

Additionally, start on the lower end of the scale, and then gradually increase to train your gut to avoid unnecessary gastric upset.

P.S. Keep in mind that sports drinks like Tailwind and Gatorade contain carbs, so include that amount in your rate per hour.

7. Fuel OPTIONS: Gels/GU’S/Blocks/Etc., and Even Real Food

A huge assortment of products made for endurance events exist in the market: gels, GU’s, blocks, and beans, as examples. Many of them provide about 20 grams of carbohydrates (thus, sugar) as a gauge.

If your body can tolerate these types of fuel, go for it! (But remember to vary the types of fuel over the duration of the long run.) However, another option is “real food” such as raisins, bananas, pretzels, and cereal. These foods can be as effective as the commercially developed “sport” products, and your body actually processes “real food” every day, and knows how to transport it.

Personally, I like to use maple syrup packets, SiS Energy Gels, various candy (ie Sour Patch Kids, jelly beans) and pretzels on my long runs/races.

Regardless of what you choose, you need to experiment, start early in your training cycle. Learn what works best for you so that you avoid any anxiety about your performance. And avoid unwanted pit stops!

Fueling your long runs isn’t rocket science, but it is important, and each runner is different! Take the time and focus to determine what’s right for you. You won’t regret it – your runs will be stronger, and definitely more enjoyable!