Excess fluid intake harms during exercise

Athletes and coaches need to reduce the excessive intake of fluids to guard themselves against the exercise-associated hyponatremia (EAH). Researchers from the University of Cape Town in South Africa found that the incidence of EAH is increasing at an alarming rate. It is the most prevalent serious medical condition encountered by endurance athletes over the past decade. The morbid medical complications associated with drinking too much fluid are dire and have even caused death. Researchers reviewed available research in an effort to provide reliable information on the topic to health professionals and the general public. Exercise-associated hyponatremia occurs when sodium levels in the blood drop below normal levels, or about 135 mmol/litre, in most cases. The condition is most commonly associated with physical activity lasting more than four hours. Many early signs and symptoms of the condition are similar to those for dehydration, and include nausea, vomiting, headache and bloating. As hyponatremia progresses, signs can include altered mental status, such as confusion and disorientation, seizures, respiratory distress, coma and even death. The best way to avoid the condition is to refrain from drinking excessive amounts of fluid, water or sports drinks while exercising. In fact, limiting the availability of fluids during races, with aid stations placed at every five kilometers, rather than smaller distances during a standard marathon, for example, has been shown effective in reducing the incidence of the condition. Medical facilities at endurance events should be equipped to analyze athletes' sodium levels and to provide appropriate treatment if they fall below normal limits. Exercise-associated hyponatremia is more dangerous than dehydration, which is more of a detriment to performance than it is to health. However, the EAH Consensus panel does not recommend athletes to refrain from drinking during exercise. The panel aims to encourage athletes to choose a middle ground with regard to drinking habits and rely on their body's internal cues rather than heed fixed fluid guidelines that cannot account for the variety of sports and athletes that are competing in endurance activities in a variety of climates. Exercise-associated hyponatremia is serious, but an extremely rare phenomenon. It is far less common than serious dehydration. To avoid experiencing either condition, the idea is still to consume fluids to try to match sweating loss. Athletes should avoid either extreme - not to overdrink or underdrink during exercise.