The Optimum Composition for Endurance Sports Drinks.
Sportscience 2006, Annual, 10
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Sports drinks aimed at enhancing endurance performance lasting several hours need to contain ~20 mM salt (sodium chloride) and ~10% carbohydrate in the form of glucose polymers and fructose. The salt and carbohydrate offset the losses of these substances caused by exercise. They also accelerate the uptake of water. Glucose polymers are used instead of glucose to keep the total osmotically active solute concentration (tonicity or osmolarity) of the drink below that of body fluids, because higher concentrations reduce the rate of emptying of the stomach and reduce the rate of uptake of water in the small intestine. KEYWORDS: carbohydrate, energy, hydration, nutrition, salt, water This article is an edited version of a literature review commissioned by a drink manufacturer on "the mechanisms ... of water uptake in sports drinks of varying carbohydrate content and tonicity ... Please explain how carbohydrates, electrolytes and tonicity affect water uptake and hydration in plain English." In our report we placed as much emphasis on the uptake of carbohydrate as of water, for the following reasons. First, in all but the hottest and most humid environments, exercise of duration and intensity sufficient to make dehydration an issue will also make supply of carbohydrate an issue. Secondly, getting the carbohydrate in is more of a challenge than getting the water in. Finally, we assumed that the drink is aimed at optimizing performance of elite endurance athletes and recreational multisport or ultra-endurance athletes in competitions. For the mass market of less serious fitness enthusiasts, there is little need to worry about depletion of water, salt and carbohydrate during exercise. Indeed, fitness exercises can be performed without any concern for fluid and carbohydrate uptake.
- 2,99 €
- Category: Health & Fitness
- Published: 01 January 2006
- Publisher: Internet Society for Sport Science
- Print Length: 8 Pages
- Language: English