Question: Should isotonic drinks be taken only when exercising? Ana (Philadelphia).
Answer: Commercial isotonic drinks are designed to quickly replenish the losses of energy, water and mineral salts that are lost through sweat after intense physical exercise, performed over a long period of time or in a hot environment. These drinks contain varying amounts of simple carbohydrates (fructose, glucose, sucrose) and complex (starch and maltose) and minerals such as sodium, potassium, magnesium, calcium, chlorides and phosphates. In case of exercise of mild-moderate intensity or of short duration, the losses can be replaced with water. People suffering from hypertension should refrain from consuming this drink.