A controlled human study published in the journal Food Science and Technology Research shows conclusively that oral intake of Glico Nutrition’s Cluster Dextrin®, a formulation of Highly Branched Cyclic Dextrin (HBCD), dramatically increases endurance and benefits performance in athletic trials. The study, conducted with seven accomplished adult male swimmers, has significance for the use of Cluster Dextrin® by those engaged in vigorous physical activity at every level, both structured and unstructured.

The three discrete test trials, spaced a week apart, were tightly controlled and procedurally randomized. In each, the swimmers were administered either glucose, water as a control, or HBCD, a type of maltodextrin with a high molecular weight and narrow molecular weight distribution that is the functional component of Glico’s Cluster Dextrin®. They then carried out 10 intermittent swimming trials, beginning with 5 minutes of swimming at 75% VO₂max, followed by a 3 minute rest, and subsequently an all-out effort at 90% VO₂max to the point of exhaustion. Trials were conducted in a countercurrent water machine, and so exhaustion was indicated by the swimmer’s forward movement being reversed one full meter by the current.

The resounding result: Swimmers who’d been administered HBCD were able to perform at optimum output for 70% longer than those administered conventional glucose or water. In addition, the HBCD group exhibited higher plasma glucose when blood was tested at multiple intervals prior to swimming, suggesting that HBCD helps to sustain energy-yielding glucose levels more consistently and effectively than typical endurance supplementation using carbohydrate delivered by maltose, sucrose, or glucose.

The unique properties of HBCD, including its orderly molecular structure, in opposition to the random structure of other carbohydrate sources, are key to its ability to raise endurance and mediate balanced energy conversion over time, and proportionate to the demands of vigorous exercise. The osmotic pressure of Cluster Dextrin® solution is nearly nil, which moves it swiftly to the small intestine. The fast gastric emptying time, in addition to enabling it to take effect faster, has the additional benefit of reducing gastrointestinal disorders such as nausea and flatulence, which negatively affect performance. Of greater impact is the effect Cluster Dextrin’s very low osmolality and consequent swift gastric emptying time has on water absorption in the small intestine, and hydration during athletic activity. It’s known that when exercise activity reaches 75% VO₂max gastric emptying is significantly reduced, allowing a large volume of conventional glucose solutions to remain in the stomach, where it not only offers no energy conversion benefit, but suppresses water absorption from the small intestine.

Cluster Dextrin® HBCD goes to the small intestine rapidly, and there distinguishes itself from glucose supplementation in its maintenance of blood glucose levels, which have been shown to be  especially important during the final stages of an exercise routine.

Add to these advantages rapid, thorough solubility and the sometimes neglected benefit of superior palatability, and it is easy to see why Glico Nutrition’s Cluster Dextrin® is holding the spotlight in the world of sports drinks. The current study proves that it boosts endurance during vigorous exercise. But just as important is the manner in which it achieves this. That it allows the body to sustain proper glucose levels without the negative effects of high-molecular weight carbohydrate supplements makes it the optimal choice in sports food supplementation right now.