Why Dual Fuel Carbohydrates Outperform Single Carbohydrates in Sports Performance

Driven by Dr. Asker Jeukendrup one of the founders of Neversecond, was one of the pioneers of the groundbreaking discovery in 2003 that revolutionized endurance sports fueling.

Before this breakthrough, it was believed that the maximum amount of carbohydrate that could be delivered to muscles was around 60 grams per hour (240 kcal/h). However, with energy expenditures exceeding 1000 kcal/h in some endurance sports, it was evident that delivering more carbohydrates could significantly support performance. This blog delves into why dual fuel carbohydrates, combining glucose and fructose, outperform single carbohydrate sources.

The Limitations of Single Carbohydrate Sources

Traditional sports nutrition relied on single carbohydrate sources, typically glucose. Despite various protocols, researchers struggled to deliver more than 60g/h to the muscles. The bottleneck wasn't gastric emptying, muscle glucose uptake, or muscle metabolism but absorption. Carbohydrate absorption is facilitated by transport proteins, primarily the sodium-dependent glucose transporter 1 (SGLT1) for glucose. At high glucose intakes, SGLT1 may become saturated, limiting further absorption.

The Advantage of Dual Fuel Carbohydrates

Introducing dual fuel carbohydrates – specifically glucose and fructose – offers a solution. Fructose is absorbed via a different transporter, GLUT5. By utilizing both SGLT1 and GLUT5, the body can absorb more carbohydrates efficiently. The first study to combine glucose and fructose found a remarkable 50% increase in oxidation rates compared to glucose alone, highlighting the superior performance potential of dual fuel carbohydrates.

Optimal Ratios and Performance Benefits

Research indicates that the best results come from a glucose-to-fructose ratio of 2:1, with an intake of 108g/h. This combination not only enhances oxidation efficiency but also minimizes residual volume in the intestines, reducing the risk of gastrointestinal issues. Athletes benefit from sustained energy delivery, improved performance, and fewer digestive problems.

Conclusion

Dual fuel carbohydrates offer a clear advantage over single carbohydrate sources. By leveraging the complementary absorption pathways of glucose and fructose, athletes can maximize carbohydrate delivery to their muscles, enhance their energy levels, and boost their overall performance. For endurance athletes looking to push their limits, dual fuel carbohydrates are the superior choice.