Carbohydrates

Carbohydrates are the body’s most readily available energy source, powering both your muscles and your brain. For athletes, they’re essential for endurance, high-intensity training, and supporting muscle growth and recovery. Skimping on carbs can lead to fatigue, slower recovery, or “bonking” during long sessions.

Carbs show up in all kinds of foods, including grains like bread, rice, pasta, and oats, starchy vegetables like potatoes, and naturally in fruit and dairy. Around exercise, quick-digesting options such as bananas, pretzels, or sports drinks can deliver fast energy right when you need it most. Carbohydrates also support the body when consumed during activities lasting an hour or more. They help to optimize performance by delaying fatigue and maintaining blood glucose levels.¹

The amount of carbohydrates required per hour will increase as the duration increases. Athletes can use a myriad of products to meet needs during exercise suchas energy gels, chews, sports drinks or granola bars.It is all about figuring out what works best for the individual athlete as the options are near limitless.

It is important to note that carbohydrate needs vary by sport, season, intensity of training, and even various stages of life. Learning how to meet your needs during these various times is key for overall energy, performance, and health.

Bottom line: Carbs are not the enemy, and ingesting the right amount at the right times can have a significant impact on your athletic performance.

Carbohydrates are one of the three macronutrients, alongside protein and fats.

They are the primary energy source for the body and brain.

Carbohydrates play a major role in supporting daily energy demands, endurance activity, and high-intensity training, as well as indirectly supporting muscle growth and development.

Carbohydrates are in a wide variety of foods, such as bread, oatmeal, pasta, rice, crackers, grains, cereal, and potatoes. They are also in dairy, fruits, and vegetables. Easily-digested carbohydrates containing minimal to no fiber are recommended before, during, and immediately following exercise.

After ingestion, the digestive process breaks down all carbs into simple sugars for absorption.

Glucose can be used immediately for energy or stored as glycogen in muscles and the liver for later use.Once those stores are depleted, taking in external (exogenous) carbohydrates becomes crucial to sustain performance and to spare muscle protein from being broken down for fuel.

It is often said that adequate carbohydrate intake not only supports endurance performance but also prevents muscle breakdown. If an athlete’s glycogen stores are depleted, it can result in fatigue and a decline in endurance and high-intensity performance.¹

Increased activity levels = need for increased carbohydrate intake.

The amount of carbohydrate required for an athlete will depend on type of activity, duration, intensity, size, altitude and individual responses. A sports dietitian can help determine these based on individual needs.

The Athlete's Plate

These plates are meant to provide general guidance. Nutrition needs may differ by age, training load, and life stage. Consult your dietitian for individualized support.

Adapted from The Athlete’s Plates, a collaboration between the United States Olympic & Paralympic Committee (USOPC) Sport Dietitians and the University of Colorado Colorado Springs (UCCS) Sport Nutrition Graduate Program.

Grain Examples

Bread, Pasta, Rice, Potatoes, Oats, Cereals

Protein Examples

Milk , Cheese, Yogurt, Chicken, Tofu, Tempeh, Fish, Meat, Legumes, Nuts, Seeds

Color Examples

Vegetables, Fruits

Fat Examples

Avocado, Oils, Nuts, Seeds, Cheese, Butter, Dressings

Fluids

Drink fluids with meals to help maintain hydration

Acute Carbohydrate Fueling Needs Before, During, And After Exercise/Competition

Carbohydrate timing is key for optimizing performance and recovery.

Before

Simple carbs are the easiest to tolerate before and during exercise. Examples include pretzels, crackers, energy gels, chews, sport drinks or carbohydrate-focused granola bars.

If an athlete is short on time pre-workout, 30g of an easily digested carbohydrate five minutes before exercise can help to support energy levels during training.

During

The general recommendation for grams of carbohydrates per hour of activity is 30-60g for activities lasting 60-90 minutes and 90g per hour for activities over 2.5 hours.² Research conducted in male athletes suggests that some individuals can tolerate and may benefit from as many as 120 g/hour.⁴ Higher carbohydrate intake often requires gut training, meaning a gradual practice of consuming higher carbohydrates during training to help the digestive system adapt. It is also important to mention that ingesting higher ranges of carbs per hour can be achieved through the use of multiple transportable carbohydrates, or different carbohydrate types. The research has looked at athletes using a blend of glucose and fructose or maltodextrin and fructose as opposed to just glucose, and found that in activities lasting >2.5 hours, the body was able to oxidize higher levels of carbs per hour leading to decreased rate of exertion and improved performance. However, the research has been only done in male athletes. If training <2.5 hours, there is no difference between these and other carbohydrate sources.^2,3

There are various ways to meet carbohydrate needs; therefore, it is important to trial different combinations to see what feels best for each athlete.

After

Combining carbohydrates with protein restores muscle glycogen and promotes muscle recovery.⁵

If an athlete is completing multiple training sessions or competitions in one day, it is recommended to consume 1-1.2g/kg per hour for the first 4 hours following exercise to more rapidly replenish glycogen stores.⁶

Why are carbohydrates so important for athletes?

Adequate carbohydrate availability in athletes has been linked to improved performance, decreased markers of inflammation, and improved bone and iron biomarkers in the setting of adequate caloric intake. However, research has shown that athletes often struggle to consume enough overall energy, most notably carbohydrates.²

If an athlete does not consume adequate carbs before or during exercise, they may experience a phenomenon known as “bonking,” which can have serious impacts on performance. A few recent studies done exclusively on males have demonstrated negative impacts on bone health, immune function, and iron biomarkers in the setting of inadequate carbohydrate intake, potentially independent of balance or energy availability.^5-8

An audit of the literature identified a significant underrepresentation of female athletes in studies of acute carbohydrate intake, highlighting a critical gap in evidence. Given potential sex-based differences in body composition, hormonal regulation, and substrate utilization, more research should be conducted to examine how inadequate carbohydrate intake uniquely impacts female athletes.⁹