CLINICAL RESEARCH REPORT : Fueling During Performance

Infinit Custom-Blended Nutrition Solutions

This article provided courtesy of Ashley Meuser at Infinit Custom-Blended Nutrition Solutions.

INFINIT Nutrition |


Popularity of endurance events is on the rise, and without the proper nutrition, performance can suffer. However, nutrition can be the most confusing aspect of endurance performance and overwhelming for the beginner athlete. The most important nutrition aspects to focus on for these events are proper calories, fluid intake, carbohydrates, electrolytes, and osmolality. Osmolality and carbohydrate source are important aspects effecting performance and proper absorption.


Osmolality is used to describe the concentration of particles dissolved in a solute. The osmolality of a solution is affected by the nutritional components that go into your sports drink. The osmolality of our own body’s fluids is approximately 280mOsm/kg.
Solutions with an osmolality around 280mOsm/kg are considered isotonic. Those with a lower or higher osmolality are referred to as hypotonic and hypertonic, respectively. The osmolality of a sport drink can affect and athlete’s performance. Optimal
absorption of fluids happens when your sports drink solution is isotonic. In addition, isotonic beverages result in rapid gastric emptying, decreasing gastrointestinal distress.1 Research has shown that as the osmolality of your sports drink increases above 280mOsm/kg, efficient uptake from the GI tract decreases. GI complaints and issues during an endurance event can hinder performance. Rehrer et al. found that individuals consuming hypertonic solutions were likely to experience GI distress during a half Ironman event.2 In addition, hypertonic solutions can actually draw fluid out of the body. This delays rehydration, can cause dehydration and can therefore reduce performance.1

Infinit Nutrition’s patented Osmo-fit™ system automatically calculates the osmolality of a customized formula, guaranteeing that the solution is isotonic and easily digested.


Most of the sports drinks on the market currently use one type of carbohydrate source. A single carbohydrate source limits the absorption of these necessary calories. Carbohydrate oxidation of glucose is limited by intestinal absorption of carbohydrates
and dependent on a transporter that becomes saturated at a carbohydrate intake rate of 60g/hr. When another carbohydrate source is ingested with glucose, oxidation rates went well above 60g/hr.3 In fact, multiple carbohydrate sources resulted in up to 75% higher oxidation rates than glucose alone.4 Other benefits of including multiple carbohydrate sources in your sports drink include increased fluid delivery and oxidation efficiency, decreasing the likelihood of experiencing GI distress, reduced fatigue, and improved exercise performance.5

Infinit Nutrition’s products are formulated with three different sources of carbohydrates – maltodextrin, dextrose, and sucrose. This allows increased absorption and increased performance. *

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose,
treat, cure, or prevent any disease.

1. Gisolfi, C.V., et al. Effect of beverage osmolality on intestinal fluid absorption during exercise. J. Appl. Physiol. 85(5): 1941-1948, 1998.

2. Rehrer, N.J. et al. Physiological changes and gastrointestinal symptoms as a result of ultra-endurance running. Eur. J. Appl. Physiol.

3. Jentigens, R.L., et al. Oxidation of combined ingestion of glucose and fructose during exercise. J. Appl. Physiol. 96: 1277- 1284, 2004.

4. Jeukendrup, A.E. Nutrition for endurance sports: Marathon, triathlon, and road cycling. J. Sports Sci. 29(S1): S91-S99, 2011.

5. Jeukendrup, A.E. Carbohydrate and exercise performance: the role of multiple transportable carbohydrates. Curr Opin Clin Nutr. 13:452-457, 2010.