Personalized Nutrition for the Enhancement of Elite Athletic Performance

Carbohydrate and Hydration Recommendations Are Evolving, but Still Controversial

• Early studies identified carbohydrate (CHO) as a key performance fuel and hydration as a factor in endurance.
• Despite popular guidelines (e.g., to avoid >2% dehydration), recent ecologically valid studies challenge this assumption, especially in elite athletes.
• The field still grapples with low reproducibility, lab-based testing limitations, and industry bias in supplement research.
• Individual characteristics like sweat rate, metabolic preference, and gastric emptying vary widely, complicating standard recommendations.

One-Size-Fits-All Interventions Underserve Diverse Athlete Needs

• Even among elite athletes (e.g., Ethiopian Olympic runners), sweat rates can range from 0.8 to 3.6 L/hour, showing large interindividual variability.
• Female athletes remain underrepresented in sports nutrition research, despite having distinct physiological needs.
• Real-world performance demands differ from lab conditions, highlighting the need for more ecologically valid testing environments.
• Wearable tech (e.g., CGMs, sweat patches) can support individualized recommendations by monitoring hydration, glucose, and thermoregulation in real time.

The Promise and Pitfalls of Genetic and Multi-Omics Personalization

• Advances in genomics, metabolomics, proteomics, and transcriptomics enable individualized insights into fueling and recovery.
• However, genetic testing for sports performance currently lacks clinical utility, and commercial offerings often outpace scientific validation.
• A poly-omics approach, combined with AI, could identify individualized nutrition strategies, but data interpretation, standardization, and application remain major hurdles.

Artificial Intelligence Will Be Key to Scaling Personalized Nutrition

• AI and machine learning offer the ability to process complex, real-time data and generate dynamic, evidence-based recommendations.
• With the emergence of 6G networks, data from multiple devices can be integrated seamlessly, even in competition settings.
• Future applications include real-time fuel and hydration adjustments based on individual metabolism, activity demands, and environmental conditions.
• Still, these tools must be used ethically and be grounded in valid, interpretable data, not simply adopted for their novelty.

Conclusion and Forward-Looking Perspective

• Personalized nutrition is not just about identifying the “best” supplement or macronutrient dose, but about capturing and responding to variability in athlete biology, context, and competition demands.
• The field must move from generalized guidelines to real-time, context-sensitive, and individualized approaches, aided by bioinformatics and next-generation technologies.
• Though focused largely on endurance sports, the implications extend to all disciplines, including team and strength-based sports.