Walk through a grocery store—or scroll through social media—and the message is nearly impossible to miss: more protein.

Protein cereal. Protein cookies. Protein coffee. Protein ice cream. Even foods that were never meant to be major protein sources are being reformulated and marketed by the number of grams splashed across the front of the package.

Protein matters. Athletes need it to repair muscle, support adaptation and recover from training. But our fixation on protein has created a nutritional blind spot: many athletes are prioritizing the nutrient that helps them rebuild while under-consuming the nutrient that helps them perform.

That nutrient is carbohydrate.

Carbohydrates are not empty by definition, and they are not something athletes need to earn. They are the body's most efficient fuel for high-intensity work. The question is not whether athletes should eat carbs. It is how much they need, when they need them and which carbohydrate-containing foods can also contribute fiber, fats, protein and micronutrients.

What happens when we eat carbohydrates?

Carbohydrates are broken down primarily into glucose. Some glucose circulates in the blood, where it is available to the brain and working tissues. The body stores additional glucose as glycogen in the liver and skeletal muscles.

Muscle glycogen is local fuel: working muscle can draw on its own stores as exercise intensity rises. Liver glycogen helps maintain blood glucose, including the supply needed by the brain. Fat is also a valuable energy source, especially at rest and during lower-intensity movement, but carbohydrate can produce energy more rapidly and with a lower oxygen cost. As intensity increases—during a sprint, a hard interval, a breakaway, a shift on the ice or the closing miles of a race—the body relies increasingly on carbohydrate.

This is why sports-nutrition guidance does not prescribe one static carbohydrate number for every athlete. Consensus guidance from the Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine recommends matching carbohydrate availability to training and competition demands—roughly 3 to 10 grams per kilogram of body weight daily, with 30 to 90 grams per hour during prolonged exercise depending on duration and tolerance.

Those are not fringe “carb-loading” ideas. They are mainstream performance-nutrition principles.

The performance cost of avoiding carbs

The most useful evidence does not come from a laboratory theory. It comes from what happens when trained athletes attempt to perform with different fuel availability.

In a controlled study of world-class race walkers, athletes followed one of three energy-matched diets during three weeks of intensified training: high-carbohydrate availability, periodized carbohydrate availability or a ketogenic low-carbohydrate, high-fat diet. The athletes eating the ketogenic diet became much better at burning fat. Their aerobic capacity improved, too.

But their performance did not.

The high-carbohydrate and periodized-carbohydrate groups improved their 10-kilometer race-walk times by 6.6% and 5.3%, respectively. The low-carbohydrate group showed no improvement. Researchers found that the ketogenic approach increased the oxygen required to maintain race-relevant speeds—making the athletes less economical even as they became more efficient fat burners. A later replication reached the same conclusion.

The lesson is not that fat is bad. The lesson is that becoming good at using one fuel does not change the demands of high-intensity performance.

The pattern also appears outside endurance racing. A 2024 systematic review covering 61 studies in soccer found that carbohydrate intake before and during matches improved speed and sprint frequency, delayed fatigue and helped preserve shooting performance and cognitive function. The review also noted that muscle glycogen remained low as long as 48 hours after a match—an important reminder for tournament weekends and athletes training on consecutive days.

Marathon data tell a similarly practical story. In an observational study of 257 runners at the London Marathon, athletes who consumed more than 7 grams of carbohydrate per kilogram of body weight the day before the race ran faster and maintained their pace better than those consuming less, even after researchers adjusted for sex, body size and training.

Carbohydrate does not replace training. It allows athletes to access the training they have already done.

Two athletes, two very different fuel plans

Imagine two soccer players arriving at a Saturday tournament.

The first athlete has been taught that a “healthy” breakfast should be as low in carbohydrates as possible. She eats eggs and a protein shake, then begins a morning match with little carbohydrate coming in and partially replenished glycogen from Friday's practice. By the second half, she is still fit and motivated—but her readily available fuel is dwindling. Her legs feel heavy, repeated sprints become harder and decision-making requires more effort. She may interpret the fade as a conditioning problem.

The second athlete also eats protein, but it does not crowd everything else off the plate. Her breakfast includes oats or granola, fruit and yogurt. She has an easy-to-digest carbohydrate snack before the match and refuels between games. Her plan is not “sugar for sugar's sake.” It is a deliberate attempt to begin competition with adequate glycogen and maintain carbohydrate availability as the workload accumulates.

This example is simplified; fatigue can have many causes. But it illustrates a common mistake: an athlete can consume plenty of protein and still be underfueled.

Not all carbohydrate-containing foods are nutritionally identical

Defending carbohydrates does not require pretending that every carbohydrate-containing food offers the same nutritional value.

A carbohydrate gram is a unit of macronutrient, not a complete description of a food. Whole and minimally processed foods can bring fiber, vitamins, minerals, unsaturated fats, protein and plant compounds along with their carbohydrates. Highly refined sports products can also serve a legitimate purpose when rapid digestion is the priority—for example, during a race or between closely spaced games.

Context changes the “best” choice.

Immediately before or during hard exercise, lower-fiber, lower-fat carbohydrates are often easier to digest. At breakfast, several hours before activity, after training or as part of an everyday snack, a mixed food can provide more sustained energy and a broader nutrient profile.

That is the difference between advocating for carbohydrate availability and promoting “carbs for carbs' sake.” Athletes need fast fuel sometimes. They also need real meals and snacks that contribute to the total diet.

What the macros in 3 Bears Granola actually mean

When I created 3 Bears Granola, I wasn't chasing the highest possible protein number. I built it from ingredients I recognized and wanted to feed my own family: organic gluten-free rolled oats, nuts, seeds, pure maple syrup, extra-virgin olive oil, coconut and dried fruit.

Our Original Granola provides 290 calories per half-cup serving, with 29 grams of carbohydrate, 5 grams of fiber, 8 grams of protein and 17 grams of fat, along with measurable iron, magnesium, phosphorus, copper and manganese. Those numbers tell a fuller story than a single protein claim: the oats and maple syrup supply the carbohydrate, the seeds and fruit contribute fiber and micronutrients, and the nuts, seeds and olive oil bring predominantly unsaturated fat. It's a mixed food, not a sports gel or a protein bar in disguise—and that's exactly the point.

Protein and carbohydrates are teammates, not competitors

The answer to protein culture is not a new fear of protein.

Athletes need adequate protein distributed across the day. But once protein needs are met, adding more protein does not compensate for inadequate carbohydrate or total energy. In young athletes, this matters even more: food must support growth, development, school and daily life in addition to sport. Recent clinical guidance notes that youth athletes can deplete glycogen more quickly than adults and that very high protein intakes offer no additional adaptive benefit.

A useful way to think about the division of labor is simple:

Carbohydrates help supply the work. Protein helps rebuild from the work. Fat supports energy needs and health.

Most meals should contain a combination. The proportions and timing change with the athlete and the day.

Fuel the athlete in front of you

Carbohydrates have spent years being framed as something to restrict, offset or fear. For athletes, that message can become more than confusing. It can undermine the quality of training, delay recovery and make normal fatigue feel like personal failure.

The goal is not to chase the largest carbohydrate number any more than it is to chase the largest protein number. The goal is to eat enough total energy, match carbohydrate availability to the work being asked of the body and choose foods that serve the moment.

Sometimes that means fruit, oats and granola at breakfast. Sometimes it means rice or potatoes at dinner. Sometimes it means a sports drink or gel because the game or race is already underway. And sometimes it means pairing carbohydrate with protein after the work is done.

Athletes do not need another reason to fear food. They need to understand what food does.

Carbohydrates are not a nutritional failure. They are fuel—and when chosen and timed well, they help athletes show up ready for what matters.

References

1. Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal of the Academy of Nutrition and Dietetics. 2016.

2. Burke LM, et al. Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. The Journal of Physiology. 2017.

3. Burke LM, et al. Impairment of exercise economy and performance in elite race walkers by a ketogenic low-carbohydrate, high-fat diet is reproducible. PLOS ONE. 2020.

4. Pueyo M, Llodio I, Cámara J, Castillo D, Granados C. Influence of Carbohydrate Intake on Different Parameters of Soccer Players' Performance: Systematic Review. Nutrients. 2024;16(21):3731.

5. Atkinson G, et al. Pre-race dietary carbohydrate intake can independently influence sub-elite marathon running performance. International Journal of Sports Medicine. 2011.

6. Jeukendrup AE. A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports Medicine. 2014.

7. Hecht C, Bank N, Cook B, Mistovich RJ. Nutritional Recommendations for the Young Athlete. Journal of the Pediatric Orthopaedic Society of North America. 2023;5(1):599.

Nutrition needs vary by age, health status, training load and sport. Athletes seeking individualized guidance should consult a registered dietitian nutritionist, ideally one specializing in sports nutrition.