The Case For Junk Food As A Runner

Why "clean eating" can backfire when you're training hard

One of my favorite traditions this past year has been showing up on Saturday morning with a pink box of Voodoo Donuts and surprising the team with a sweet treat after our weekly long run. It’s always a hit.

And without fail, when I mention this tradition to non-runners, someone will raise an eyebrow and say something like “Wait… Olympic-level athletes are allowed to eat donuts? Aren’t they supposed to treat their bodies like temples?”

I usually pause before answering. Not because it’s an unfair question, but because it reveals how quickly we turn food into a morality statement.

The bigger issue is this: most people don’t understand the difference between eating for health and eating for performance. Even though there is significant overlap, these strategies diverge in meaningful ways. High training volumes change what the body needs and how it processes and stores calories.

So yes, sometimes the right nutrition strategy after a big long run can be a donut. Here’s why.

Endurance athletes are not sedentary people who run

We live in a world where the main nutritional problem is no longer scarcity. It’s abundance. And more specifically: abundance that requires almost no effort.

For most of human history, movement and eating were coupled behaviors. If you wanted calories, you had to hunt them or gather them. Our physiology was built in that environment.

Now we live in the opposite reality. Food is engineered to be hyper-palatable, cheap, and available with the tap of a button. For the average person who moves very little and relies heavily on ultra-processed foods, a mismatch emerges: energy intake remains high while energy demand remains low.

That’s a recipe for metabolic problems over time. And yes, in sedentary populations, higher exposure to processed foods is associated with worse health outcomes.

But it’s an error to apply these findings directly to endurance runners in heavy training or competition.

In this context, energy expenditure is high, carbohydrate delivery is performance-critical, and high-fiber options can become a liability. Low-bulk, rapidly digestible foods aren’t “bad choices.” They’re often the only practical way to hit fueling targets without wrecking your gut or drifting into chronic under-fueling.

For most serious distance runners, mainstream nutrition discourse misses the mark. In some cases, following that advice becomes actively harmful.

Calorie delivery beats food purity

A lot of elite athletes don’t have a food “quality” problem. They have a delivery problem.

When you train 10+ hours per week, you burn an absurd amount of energy. If you couple that with the documented risks of under-fueling, this changes the calculation from “What’s the cleanest food I can eat?” to “How do I get enough fuel in, consistently, without my gut revolting?”

If you tried to eat 2,000 calories in chicken breast, brown rice, and asparagus, you’d fill up really fast. Those foods are high in fiber and bulky. They take up space and digest really slowly. Large amounts of fiber close to training can increase GI risk for many athletes.

Alternatively, if you grab food from Chipotle or a bakery, it’s not that hard to eat 2,000 calories in two normal-sized meals. The caloric density in those meals is totally different.

Image borrowed from Michael Easter’s Substack article.

Look at the graph above. To get roughly 140 calories from apples, you’d need to eat 8-10 ounces. A candy bar delivers that same amount of energy in an ounce. That gap is why so many endurance athletes (myself included) rely on refined carbs, sports nutrition products, and yes, sometimes fast food.

These foods are essentially pre-processed. They expedite the delivery of calories because the stomach has to do less work, allowing nutrients to enter the bloodstream faster.

None of this makes junk food “healthy.” But it's useful in the right window. For someone sedentary, a 1,000-calorie fast-food order might be a step towards metabolic disease. For a distance runner training hard, it can be rocket fuel.

Endurance athletes handle carbs differently

As I wrote about in this popular newsletter, high-carb fueling is making a resurgence in endurance sports right now. But despite the positive benefits that come from this approach, it’s still hard to disentangle the sports-specific advice from the “carbs are evil” messaging you’ll see by scrolling through many health influencers' profiles. This can be traced back to a crucial difference in how sedentary people process carbohydrates compared with athletes.

Carbohydrates are not inherently problematic. The “problem” is what happens after you eat them. If your muscles are inactive, glucose has nowhere urgent to go. It lingers in your bloodstream, and your body needs to secrete a lot of insulin to manage it. Eventually, unused glucose gets stored as fat.

If you train a lot, your body relies on a different system. It creates a bigger, faster “drain” for glucose.

GLUT4 (short for glucose transporter type 4) is essentially a doorway that lets glucose move from your blood into the muscle. Endurance training increases how many of these doorways you have and how easily they open.

One study found that trained muscle had substantially higher GLUT4 content than untrained muscle and that trained athletes pull more glucose into working muscle during hard exercise.

This matters even after you finish a workout. Post-exercise, your muscles are desperately trying to refill glycogen (the stored form of carbohydrate that was just depleted). In that window, ingested carbs and sugar don’t just “hit your bloodstream” and linger. Rather, they get transported into the muscle and converted into fuel reserves. That’s one reason refined carbohydrates can be surprisingly useful: they deliver glucose quickly at the exact moment your body is most ready to absorb it.

Endurance athletes don’t just use more glycogen; they store more of it and cycle through it constantly. Another classic finding is that trained athletes have a larger glycogen reservoir, whereas a sedentary person has smaller storage tanks and slower turnover.

If you put these facts together, it reveals an important biological truth: Endurance training changes the destination of carbohydrates. It turns high-carb intake from a risk factor (for sedentary people) into a tool for athletes, because muscles become a demanding consumer of glucose.

Most runners obsess over how hard they can push. Fewer ask the better question: how much work can your body actually absorb?

That distinction is why I partnered with Nomio. I first came across it last summer when athletes I coach started asking about it ahead of the Tokyo World Championships. Evan Jager, whom I previously coached and now works with Nomio, walked me through the product and the mechanism. I ordered it for my Nike athletes that same week.

The data are clean and compelling: Nomio has been associated with roughly 12% lower blood lactate at submaximal intensities, antioxidant effects, and improved long-term training adaptations. In plain terms, it helps you tolerate and absorb more work, which is where real breakthroughs come from.

I think of it as the metabolic version of super shoes. Super shoes didn't make anyone tougher. They reduced the mechanical cost of running, allowing athletes to handle more volume and intensity. Nomio is solving the same equation from the inside out.

It's also showing up at the highest level of the sport, where selection pressure is highest. Cole Hocker and Andreas Almgren are using it consistently. My read on elite sport is Darwinian: if something survives at the top, it's doing something real. Nomio is offering 15% off at The Feed with code NomioTRE15.

Practical guidance: the two-layer diet

Your base diet (which I’ll call layer 1), should rely on minimally processed foods, fiber and micronutrient-rich carbohydrates, and healthy fats. Even for athletes training hard, this layer makes up most of your meals, especially on easy or moderate training days.

Your performance layer (layer 2) represents a shift in priorities. Here, you have to respect a different constraint: convenience and delivery. On your hard training days with lots of energy depletion, you should worry about gut comfort, sufficient carb intake, and practicality. This can mean refined grains, liquid carbs, gels, or sports drinks.

You don’t have to make this very fancy. This 2015 study proves that point. Researchers had 11 men complete a 90-minute glycogen-depleting ride, then recover for four hours with a meal right after completion and 2 hours later. In one condition, they refueled with sports-nutrition products. In the other, they were fueled with a McDonald's fast-food meal (matched for total calories and macronutrients). After 4 hours, they then did a second 20km time trial.

The analysis showed no meaningful differences in muscle glycogen restoration or time-trial performance between the fast-food and sports-supplement groups. This doesn’t make fast food a health food, but it shows that, acutely, carb delivery supercedes food labels.

When the goal is rapid refueling and the limiting factor is intake, your body cares much more about carbohydrate and calorie delivery than whether the package looks “clean.”

Calories first, optimization second

On hard days, “good enough and executable” beats “perfect on paper and never done.” That’s why I’ll argue that what we casually label as junk food can serve a real purpose in an athlete’s diet. It’s also why I’m still going to show up to Saturday long runs with a box of Voodoo donuts.

If you think about the hierarchy of sports nutrition needs (as I’ve written about for recovery and training theory), this fits neatly: eating enough is the foundation. Hitting total energy intake matters more than micromanaging where every calorie came from. Your muscle doesn’t care where you bought your carbohydrates. It cares whether it has enough glycogen to do the work.

Once you’ve nailed adequacy, you can start optimizing quality. But you don’t get to skip step one.