Electrolytes are ionic solutions (salts), existing in nature in the form of minerals. Electrolytes are responsible for keeping the body properly hydrated so the muscles and nerves can function properly.
Since the human body is composed mostly of water, it is important that we take in adequate amounts of these minerals. Drinks containing sodium and potassium salts help replenish the body's water and electrolyte levels after dehydration caused by exercise. Athletes exercising continuously for three or more hours (e.g. marathon or triathlon) that do not consume electrolytes risk dehydration. What is more, when we are well-hydrated, we are able to release toxic internal wastes such as harmful chemicals, urea and ammonia.
An electrolyte drink can be homemade by using the correct proportions of water, sugar, salt, salt substitute for potassium, and baking soda. Electrolytes are commonly found in fruit juices, coconut water, sports drinks, milk, and many fruits and vegetables-- whole or in juice form.
Sources / Links
Health Maven
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Map of the Rivanna Trails