The 3 Musketeers: Sodium, Potassium and Chloride

Sodium is a vital electrolyte, especially for runners with high sweat losses. Many endurance athletes require more than the Tolerable Upper Level for sodium (2.3 gm/day) and chloride (3.6 gm/day). Beverages containing carbohydrate are recommended in sports lasting >1 hour, and sports drinks are recommended in events lasting > 2 hours. Sports drinks provide .5-.7 gm/liter sodium and .8-2.0 gm/liter of potassium as well as carbohydrate. This combination replace sweat electrolyte losses, sodium encourages thirst and fluid retention and the carbohydrates provide energy. Sweat contains an average concentration of 1 gm sodium/liter, modest amounts of potassium and small amounts of other minerals such as magnesium and chloride. Errors in proper hydration can result in dehydration, hypohydration, or hyponatremia. Nancy Clark MS, RD provides the following recipe for a homemade sports drink: mix 4 Tbsp sugar, ¼ tsp salt, ¼ cup orange juice and 3.5 cups cold water. Some people substitute lemon juice or unsweetened Koolaide mix for the orange juice for a variety in flavor.