Sport drinks are electrolyte replacement beverages popular among athletes to replace water lost during exercise. It is important to drink plenty of fluids during strenuous exercise, especially during hot weather, because the body requires water for efficient cooling and for efficient operation of the kidneys in moving wastes from the blood. glucose sodium sport drinks provide extra sugar and sodium, which also promote rapid fluid uptake by the small intestine. Some beverages contain glucose polymers (maltodextrins), small fragment of srach. Glucose polymer beverages may be more effective than glucose drinks in replacing carbohydrates and in increasing blood sugar during endurance events (more than two hours in duration).
They do not slow the passage of liquid through the stomach as a high-glucose concentration does. Simple carbohydrates seem to provide their greatest benefit when exercise exceeds 60 minutes. A potential benefit of consuming glucose replacements during exercise is that fluid intake may increase if the taste is more appealing than plain water. The carbohydrate-electrolyte sport drink should be mixed so that the carbohydrate concentration is less than 10 percent to minimize retention by the stomach. On the other hand, the carbohydrate concentration should be at least 6 percent to improve endurance. When fluid loss is reduced by a cold environment such as in crosscountry skiing, fluids with a carbohydrate concentration greater than 10 percent are appropriate.
Sport drinks often contain more sugar and salt than are needed for optimal absorption of fluids, and they often contain less potassium than a glass of orange juice. Plain water, which is both easily absorbed and palatable, effectively replaces water lost with strenuous exercise. In general, there does not seem to be any need to replace electrolytes lost through sweating by consuming expensive beverages. Sport drinks appear likely to improve performance only in endurance exercise or day-long events. Diluted fruit juices are usually adequate electrolyte replacements. Fruit juices should be diluted at least twofold from standard preparations to prevent delayed gastric emptying. Electrolytes and carbohydrates are readily replenished by eating a banana, fruit, or crackers with water. Many commercial soft drinks contain caffeine, which acts as a diuretic. Therefore, athletes are advised to limit their intake of such beverages.
