Daily Carbohydrate Intake: Recommendations for Athletes, Tables

Carbohydrates are considered the most significant energy source for all excitable tissues (muscular and nervous) in sports nutrition. Carbohydrates come from the diet, as part of food supplements with proteins and/or fats, and in sports drinks. Besides providing energy, carbohydrates regulate satiety, blood glucose and insulin levels, fat metabolism, and the function of the small and large intestine (microbiome, mucosal digestion, endothelial state, etc.) among other things (Cummings J.H., Stephen A.M., 2007). Carbohydrates play a proven role in maintaining immunity (Bermon S. et al., 2017).

Daily Carbohydrate Intake in Sports

Realities and Recommendations In sports nutrition, the total daily carbohydrate need (basic indicators) and carbohydrate supply during training and competitions (Energy Metabolic Rate – EMR) are distinguished. The daily carbohydrate intake is usually calculated by summing the carbohydrate expenditure during training, competitions, and the rest of the day.

Actual Daily Carbohydrate Consumption in Different Sports and Recommendations

Various studies reflect the actual carbohydrate consumption in regular diets across different sports. The summarized data is presented in Table 1.

Table 1. Actual Daily Carbohydrate Intake in Different Sports

Official recommendations for daily carbohydrate intake are based on the athlete’s level of physical activity (Potgieter S., 2013) and are expressed in g/kg/day rather than as a percentage of total EMR.

Comparing Recommendations and Actual Carbohydrate Consumption in Different Sports F. Wardenaar and colleagues (2017) compared the actual carbohydrate consumption of athletes in various sports with recommended values.

Recommendations for Daily Carbohydrate Intake During Training and Competitions

Ensuring athletes’ energy during training and competition is crucial for maintaining physical fitness. The body’s energy reserves are supplied by blood glucose, liver glycogen, and muscle glycogen. Intense training of two to three hours depletes normal glycogen stores, necessitating the use of muscle fatty acids and proteins for energy. After depleting glycogen stores in a training session, at least 24 hours are required to replenish glycogen stores using drinks, food, and functional athlete nutrition with a high Glycemic Index (GI).

L.M. Burke and colleagues (2011) outlined the principles of energy replenishment after training through the athlete’s daily diet and special sports products:

• High-intensity, high-volume training requires a significant daily intake of carbohydrates for energy and glycogen replenishment.
• Target carbohydrate intake should be based on body mass (or muscle mass) and training load, with feedback between daily carbohydrate intake and performance for quick nutrition management.
• If there’s less than 8 hours between training sessions or competitions, athletes should consume carbohydrates soon after to speed up glycogen replenishment; insufficient carbohydrate intake leads to inefficient energy store recovery.
• For maintaining energy stores, additional protein intake in daily meals or snacks is beneficial, especially when carbohydrate intake is suboptimal.
• Pre-training carbohydrate consumption aims to maximize intramuscular glycogen stores for endurance over 90 minutes. Pre-competition ‘carbohydrate loading’ is a strategy for maximizing glycogen storage.
• Post-training, glycogen stores should be replenished quickly, along with rehydration. The closer the training sessions, the higher and more frequent the carbohydrate intake should be. However, there’s a physiological limit to carbohydrate absorption, depending on individual athlete characteristics and the types of consumed sugars.
• Carbohydrate oxidation rate is a limiting factor in carbohydrate loading. Optimal carbohydrate content in energy drinks is 6-8%, but practical usage suggests 4% is sufficient. The oxidation rate is 60-70 g/hour, and there’s no reason to exceed this. Sports drinks with combined carbohydrates (e.g., glucose + fructose) increase oxidation rates by 40-50%.
• During intense physical activity, carbohydrate expenditure always exceeds endogenous carbohydrate stores, necessitating additional intake.

This article provides a comprehensive overview of carbohydrate intake for athletes, emphasizing the importance of balancing nutrition with training and competition needs.