Fluid replacement is essential when working or training hard, especially in the heat. The body's balance of water and other minerals (electrolytes) must be maintained in order to function properly. The question is, what drink is best to replace those lost fluids?

Water

The obvious, natural choice. However, during hard work or exercise, sodium, as well as other minerals are lost through sweat and water will not replace those. In addition, drinking water will trigger urination, which will further dehydrate the body. Drink too much water and there is a risk hyponatremia, an abnormally low level of sodium in the blood. Although a small risk, it can cause seizures, coma and even death.

To help the body hold on to the water and avoid the risk of sodium loss, adding a pinch of salt is recommended (about a teaspoon per gallon). At that level, it will be tasteless.

Fluid-replacement drinks
 

Sports drinks like Gatorade and POWERade have been shown to be more effective than plain water because they contain many of the elements lost through sweat, as well as sodium which helps the body hold on to the water. The downside of sports drinks is that they are more expensive.
 

Coconut water

Though not in the mainstream as much as sports drinks, coconut water as a fluid replacement has been making headway.
The United Nations Food and Agriculture Organization (FAO) has attested to its benefits and has been granted a patent for it.

Apart from the nutritional benefits of coconut water, here is an additional, and very interesting fact from the FAO.

"It's a natural isotonic beverage, with the same level of electrolytic balance as we have in our blood. It's the fluid of life, so to speak." In fact, during the Pacific War of 1941-45, both sides in the conflict regularly used coconut water - siphoned directly from the nut - to give emergency plasma transfusions to wounded soldiers."
 

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