There’s No Space For “Guilt” In Endurance Fueling

There’s an implicit message floating around endurance sports that equates processed food with “guilt.” Here’s why we think that's bogus. 

Photo: Getty Images

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Sports nutrition has come a long way. 

At early iterations of the Boston Marathon, in lieu of aid stations, runners might sip whiskey, brandy, or other alcoholic beverages handed to them by crew on bikes. The 1924 Paris Marathon featured a fluid station that provided sips of wine to willing runners. 

Race fueling and hydration weren’t well understood in the early 20th century, and eating and drinking during events (even long ones like the marathon) was seen as a sign of weakness. The 1904 Olympic Marathon in St. Louis included only two water stations, both after the half-marathon mark. 

In 1983, Canadian Olympic marathoner Brian Maxwell created the PowerBar after an epic bonk in a high-stakes race. He wanted to create a reliable, scientifically formulated endurance fuel that could be mass produced. Gu was founded in 1994 with the goal of delivering a concentrated fuel in gel that athletes could ingest without stopping to unpeel a banana or unwrap a bar. 

General guidelines recommend you take in 30-90g of carbs per hour of activity, but trying to get that fuel from whole foods can take a toll on the body, since not many fruits, nuts, or cookies address the specific mid-race nutritional needs of athletes. When you exercise, blood is diverted away from the gut, and the harder you are exercising, the more this occurs.  This is why many whole food options can be harder to digest during specific effort. The human body isn’t naturally suited to absorb nutrition while exercising, which is why many “natural” food options don’t work well for in-competition fueling. The goal for eating while exercising is optimal performance, not necessarily health. That’s what daily diet and nutrition are for.  It’s helpful to think about separating daily nutrition from inter-workout and sports specific nutrition. 

Our understanding of the science behind endurance fueling has evolved, but the advertising and cultural conversations around it feel stuck in an early-20th-century idea of machismo and whole food “purity.” 

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Guilt-Free Fueling

A recent ad from a sports nutrition manufacturer boasted that their gels were “guilt-free” and featured only clean ingredients. The brand positioned its products as an alternative to “sugary” sports nutrition like standard gels and chews, implying that athletes should feel guilty for consuming processed and high-sugar foods as racing fuel.

Our bodies actually run quite well on sugars. The funny thing is that these “guilt-free” food blends still contain sugars (i.e. carbohydrates), including fructose, which can land some folks running for the nearest portable toilet.

While an ideal diet overall would consist of primarily minimally-processed foods without a ton of added sugar, your body’s needs are substantially different when you are exercising. Specialized sports-nutrition foods are formulated to be digestible and to provide an optimized ratio of nutrients (electrolytes, carbohydrates, fats, and protein)  necessary for your body during exercise. For athletes interested in performance, choosing a nutrition product that is tailor-made to be consumed during activity can alleviate the anxiety that they are missing out on something that their body needs. 

Vague terms like “guilt-free” aren’t helpful and can sidetrack athletes who should be focused on getting enough fuel in, not how “guilty” they should feel after eating it. Evidence shows that fasted or under-fueled training is detrimental to athletes’ health and performance. As an athlete, the greater need is to take in sufficient calories during prolonged exercise, often through whatever sources your body can tolerate. 

Carbs, which all eventually break down into glucose, are the body’s preferred (and most efficient) source of energy. However you get them is up to you, but judging where those nutrients come from is a tactic that isn’t based in science, and it needs to stop. For some athletes, less-processed products may actually cause an increased risk of gastrointestinal issues due to their fructose and fat content, both of which can be common GI irritants during exercise. 

Athletes should consider their own personal needs when choosing their fuel sources.  Questions like how long the race will be, what climate the race will be in, what the terrain will be like, and what kind of stomach tolerance they have are all more important factors to consider than the “guilt” of whatever products they will be using.

RELATED: What Runners Need To Know About Eating Enough Food

endurance running and fueling
(Photo: Getty Images)

Don’t Feed Fear

You don’t have to look far to find sports nutrition companies whose marketing language focuses on how “clean” or “natural” their products are, and how easy it is to pronounce all the ingredients. The message is that any product that you can’t pronounce, or that is “unnatural,” is something to be feared and avoided. But in endurance fueling, that’s just not the case.

There is no place for fear-mongering around food in a culture that is already rife with negative messages around body image and restrictive eating. When you’re running an ultra, or even running more than 90 minutes around town, the only thing you should be afraid of is not eating ENOUGH (and bears, who may see you as an all-natural, free-range snack up for grabs).

There’s a tendency to create a mental hierarchy of energy, one that depends more on our perception of a fuel source’s “cleanliness” as opposed to how it helps us perform. When you’re exercising, the focus should be on fueling your body to feel strong, run well and prevent injury. I’d eat a dirty sock if it would help me run well. 

RELATED: What Runners Should Know About Intuitive Eating

Feed the Fire

We’re not suggesting you fuel your whole life like an ultra. Consuming only gels and flat coke would lead to vitamin and mineral deficiencies, and likely pretty poor overall health. A diet rich in nutrient-dense foods like fruits, veggies, whole grains, nuts, seeds, legumes, and lean proteins can improve your health. But is your long run or A-race the time to try to cover all of your nutritional bases? Definitely not. We’re talking about the very specific nutritional needs of a moving body over many hours on the trail. 

Reductive thinking that puts foods in “good” or “bad”, “guilty” or “guilt-free” categories can keep you from getting the nutrition you need to send it at your next race or feel good on a long run. Brands, influencers, and media outlets can all do their part to make sure that their messaging is based in science, not over-simplified marketing language that spreads misunderstanding. 

When it comes to endurance fueling, your body is not a temple. It is a high-powered furnace capable of turning things like pizza, Coke, and gels into miles, and that’s pretty incredible. Instead of policing where people are getting their energy from, we should be encouraging athletes to fuel more effectively.


Zoë Rom is Editor-In-Chief at Trail Runner, and fuels with Oreos and flat Coke while running. Kylee Van Horn, RDN is the owner of Flynutrition and enjoys sour patch kids and rice crispy treats out on the trail.

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