Why is Sodium Important?
Sodium is important in sports drinks because it:
1. Rounds out the flavor.
2. Stimulates the drive to drink leading to better hydration.
3. Is necessary for the body to function properly.
There is not a consensus on the amount of sodium that should be included in sports drinks. It depends on differences in physical activity, environment, and variability among individuals. Generally sodium should optimize flavor- it should be subtle and not inhibit drinking.
Adequate sodium intake is necessary for muscle function and even a slight depletion can cause problems. People who exercise in hot or humid environments and/or participate in high intensity exercise are at a higher risk of developing hyponatremia (low concentration of sodium in the blood). During high intensity exercise or exercise in hot environments sodium is lost in sweat. If fluid is only replaced with water it will dilute the blood causing sodium levels in the blood to drop. Symptoms of this are nausea, muscle cramps, disorientation, slurred speech, confusion, etc. Extreme cases can cause seizures, coma or death.
The best ways to prevent hyponatremia are to ensure adequate sodium intake by:
1. Using sports drinks containing sodium during high intensity exercise, or exercise in hot environments.
2. Eating salty foods before and/or during exercise.
3. Understanding your own fluid needs. Weigh yourself before and after exercise (the weight lost during exercise is almost all fluid) to figure out how much fluid needs to be replaced for adequate hydration.
4. Avoiding the use of aspirin, ibuprofen and other anti-inflammatory drugs because they increase the risk of hyponatremia.
5. During the days before exercise increasing sodium intake.
Out of the electrolytes included in sports drinks sodium is the only one that research has shown to play any significant role in rehydration.
