What is recommended that endurance athletes consume? A complete nutritional guide

October 7, 2025 •

4 min read

Over 80% of endurance athletes fail to meet their carbohydrate recommendations, leading to suboptimal performance and recovery. This guide explains what is recommended that endurance athletes consume to ensure adequate fueling, promote muscle repair, and maintain optimal hydration for peak athletic performance.

Quick Summary

Endurance athletes need a high intake of carbohydrates for sustained energy, sufficient protein for muscle repair, and healthy fats for long-duration fueling. Strategic nutrient timing and adequate hydration before, during, and after exercise are crucial for maximizing performance and recovery.

Key Points

Carbohydrate-Focused Diet: Endurance athletes require high daily carbohydrate intake (5–12 g/kg) to fuel training and replenish muscle glycogen stores, primarily from whole grains, fruits, and starchy vegetables.
Strategic Timing: Optimize performance by timing nutrient intake correctly: eat complex carbs and moderate protein 1–4 hours before exercise, take simple carbs and electrolytes during long sessions, and combine carbs and protein within an hour post-workout for recovery.
Prioritized Protein Intake: A daily protein intake of 1.2–2.0 g/kg is recommended for muscle repair and recovery, with consumption spread evenly across meals.
Proactive Hydration: Don't rely on thirst; hydrate proactively with water and electrolytes before, during, and after exercise to prevent performance-hindering dehydration.
Test During Training: Never introduce new foods, drinks, or supplements on race day. Use training sessions to find what works best for your digestive system and energy levels.
Individualized Approach: While general guidelines exist, an endurance athlete's nutritional needs are highly individual. Tailoring your diet based on your specific training volume, intensity, and personal tolerance is key.

Endurance sports, such as marathon running, long-distance cycling, and triathlons, place immense energy demands on the body, requiring a specific nutritional strategy to support performance and recovery. While the general public's nutritional needs are met by a balanced diet, endurance athletes need to focus on specific macronutrient ratios, hydration protocols, and precise timing to maintain energy, prevent fatigue, and repair muscle tissue effectively. A well-planned diet is the foundation, complemented by strategic fueling before, during, and after training and events.

The Three Main Pillars of Endurance Nutrition

Carbohydrates: The Primary Fuel

Carbohydrates are the most critical energy source for endurance athletes, as they provide the glucose needed to fuel high-intensity and long-duration activities. The body stores carbohydrates as glycogen in the liver and muscles, but these stores are limited and must be replenished regularly.

Daily Intake: Recommendations for daily carbohydrate intake vary based on training load, from 5–7 grams per kilogram (g/kg) of body weight for moderate training to 8–12 g/kg for high-volume, high-intensity periods.
Glycogen Replenishment: Consuming high-glycemic index carbohydrates immediately after a workout helps to rapidly restore glycogen stores.
Carbohydrate Sources: Focus on nutrient-dense sources like whole grains, fruits, starchy vegetables, and legumes during regular training. Before and during exercise, simple, easily digestible carbohydrates like sports drinks, gels, chews, or bananas are preferable to avoid gastrointestinal issues.

Protein: For Repair and Recovery

While less of a primary fuel source during exercise, protein is non-negotiable for repairing muscle damage and promoting recovery. Adequate protein intake is also crucial for overall health, immune function, and enzyme production.

Daily Intake: The International Society of Sports Nutrition (ISSN) suggests a daily protein intake of 1.2–2.0 g/kg of body weight for endurance athletes, significantly higher than for sedentary individuals.
Even Distribution: Spreading protein intake throughout the day (e.g., 20–30 grams per meal) is more beneficial than consuming a large amount at once.
Recovery Timing: Consuming a combination of protein and carbohydrates within the first 30–60 minutes after a workout optimizes muscle repair and glycogen resynthesis.
Protein Sources: Lean meats, poultry, fish, eggs, dairy, legumes, and tofu are all excellent protein sources.

Fats: A Long-Lasting Energy Source

Healthy fats are a crucial, long-lasting energy source, especially during low-to-moderate intensity and prolonged exercise. Fats provide more than double the energy per gram compared to carbohydrates and are vital for hormone balance, nerve function, and nutrient transport.

Recommended Intake: Healthy fats should make up 20–35% of an endurance athlete's total daily caloric intake.
Healthy Sources: Include sources like fatty fish (salmon, tuna), avocados, nuts, seeds, and olive oil in your diet.

Hydration: The Cornerstone of Performance

Proper hydration is a cornerstone of endurance performance, as dehydration can significantly impair physical and mental function. It is not just about drinking water but also replacing lost electrolytes.

Pre-Exercise: Drink 17–20 ounces of fluid 2–3 hours before exercise and 8 ounces 20–30 minutes prior.
During Exercise: For activities over 60 minutes, consume 4–8 ounces of fluid every 15–20 minutes. In longer events or hot conditions, electrolyte-containing drinks are essential to replace sodium and other minerals lost through sweat.
Post-Exercise: Drink 16–24 ounces of fluid for every pound of body weight lost during exercise to rehydrate properly. Flavored milk can be an excellent recovery drink, providing carbohydrates, protein, and electrolytes.

Nutrient Timing Strategies for Peak Performance


Phase	Goal	Recommended Consumption	Example Foods/Drinks
Pre-Event Meal	Top up glycogen stores; ensure hydration.	1–4 g of carbs/kg body weight, low fat, low fiber, 1–4 hours before.	Oatmeal with banana and honey, rice with chicken breast, or a bagel with peanut butter.
During Event (>90 min)	Replenish glucose; maintain blood sugar and electrolyte balance.	30–60 g of carbs per hour, increasing up to 90 g/hr for longer events. Use a combination of glucose and fructose for higher absorption rates.	Sports gels, chews, electrolyte drinks, or bananas.
Post-Event Recovery	Replenish glycogen, repair muscle tissue, rehydrate.	Carbs (1.0–1.2 g/kg/hr) and protein (20–40 g) within 30–60 minutes.	Chocolate milk, protein shake with fruit, turkey sandwich, or yogurt with berries.

Common Pitfalls to Avoid

Trying new foods on race day: Always test new nutrition strategies during training to avoid gastrointestinal issues.
Ignoring hydration: Waiting for thirst to signal dehydration is too late. Proper hydration is a proactive, ongoing process.
Under-fueling: Many athletes underestimate their caloric and carbohydrate needs, leading to performance drops and increased fatigue.
Over-relying on supplements: Focus on a nutrient-rich whole-food diet as the foundation. Supplements should complement, not replace, a healthy diet.

Conclusion

For an endurance athlete, nutrition is far from a one-size-fits-all approach. By strategically focusing on a high-carbohydrate intake for fuel, sufficient protein for repair, and adequate hydration with electrolytes, athletes can support their rigorous training demands. The timing of nutrient consumption is as critical as the type of nutrients consumed, playing a pivotal role in performance and recovery. Individual needs and tolerances vary, so experimentation during training is vital to discover the optimal approach. Ultimately, a personalized and well-practiced nutritional plan is the key to unlocking peak performance and sustained health in endurance sports. For more in-depth information, consider consulting resources like the Gatorade Sports Science Institute for detailed sports nutrition research.

Frequently Asked Questions

For races longer than 90 minutes, easily digestible simple carbohydrates are best. These include sports gels, chews, and electrolyte drinks containing glucose and fructose. Some athletes also use whole-food sources like bananas or dried fruit.

Hydration needs are individual and depend on factors like sweat rate and climate. A general rule is to consume 4–8 ounces of fluid every 15–20 minutes during exercise. For heavy sweaters or long events, incorporating electrolytes is also critical.

Carbohydrates are the body's most efficient source of fuel for high-intensity exercise. They are stored as glycogen in muscles and the liver. Replenishing these stores is essential to prevent fatigue, also known as 'hitting the wall'.

Within 30–60 minutes post-exercise, consume a snack or meal with a 3:1 ratio of carbohydrates to protein. This helps to replenish glycogen stores and repair muscle tissue. Good options include chocolate milk, a protein shake with fruit, or a turkey sandwich on whole-grain bread.

Carbohydrate loading is a strategy used in the 24–48 hours before a competition lasting longer than 90 minutes. It involves increasing carbohydrate intake (often up to 10–12 g/kg body weight) to maximize the body's glycogen stores, providing a larger energy reserve for the event.

Before a race, avoid foods that are high in fat, fiber, or lactose, as these can cause gastrointestinal distress. Stick to familiar, easily digestible carbohydrates and a moderate amount of lean protein.

Electrolytes like sodium, potassium, and magnesium are vital for muscle function and fluid balance. Endurance athletes lose electrolytes through sweat and must replace them to prevent cramping, heat stress, and hyponatremia. This can be done with sports drinks or salty foods.