Exercise-associated hyponatremia Exercise-associated hyponatremia Exercise-associated hyponatremia, or EAH, is a fluid-electrolyte disorder caused by a decrease in sodium levels (hyponatremia) during or up to 24 hours after prolonged physical activity. This disorder can develop when marathon runners or endurance event athletes drink more fluid, usually water or sports drinks, than their kidneys can excrete. This excess water can severely dilute the level of sodium in the blood needed for organs, especially the brain, to function properly. The incidence of EAH in athletes has increased in recent years, especially in the United States, as marathon races and endurance events have become more popular.
Blood sugar level given in terms of whole blood, but most laboratories now measure and report plasma or serum glucose levels. Because red blood cells (erythrocytes) have a higher concentration of protein (e.g., hemoglobin) than serum, serum has a higher water content and consequently more dissolved glucose than does whole blood. To convert from whole-blood glucose, multiplication by 1.14 has been shown to generally give the serum/plasma level To prevent contamination of the sample with intravenous fluids, particular care should be given to drawing blood samples from the arm opposite the one in which an intravenous line is inserted. Alternatively, blood can be