An article published in FP Essentials discussed that oral electrolyte solutions are used widely for rehydration in diarrheal illness and to maintain hydration during vigorous exercise.

The authors reported that in diarrheal illness, an oral rehydration solution (ORS) is typically preferred over intravenous fluids, except for patients with severe dehydration. The preferred ORS is one similar to the glucose-containing reduced osmolarity World Health Organization (WHO) ORS. In addition, polymer-based solutions that use rice or wheat as the source of carbohydrates are also available, but these are not widely recommended. Use of other liquids, such as – sport drinks, juice, soft drinks and chicken broth, is not recommended, yet these can be considered for patients with no or mild dehydration.

This article stated that for maintaining hydration during exercise, particularly vigorous high-intensity exercises, recommendations advocate the consumption of fluids – i.e., 5 to 7 mL/kg, and a sodium-containing snack, at least four hours prior. During exercise, individuals require 200-800 mL/hour of liquid that should contain 20 to 30 mEq/L of sodium. Carbohydrate intake is advised during high-intensity exercise. While the intake of excessive sodium-free fluids should be avoided to prevent exercise-induced hyponatremia. Additional fluids – 1.5 L/kg of weight lost, can be taken after exercise to restore hydration. Meanwhile, vitamin and mineral supplements are not recommended routinely for athletes unless known deficiencies exist.

Source: FP Essentials. 2017 Aug;459:35-38.