What are electrolytes and why are they important?

Question

What are electrolytes and why are they important? What are they for?

You always hear about needing electrolytes when exercising, but what are they for?

Answer 1

An electrolyte is any substance containing free ions that make the substance electrically conductive.

In physiology, the primary ions of electrolytes are sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), chloride (Cl−), hydrogen phosphate (HPO42−), and hydrogen carbonate (HCO3−). All known higher lifeforms require a subtle and complex electrolyte balance between the intracellular and extracellular milieu.

In oral rehydration therapy, electrolyte drinks containing sodium and potassium salts replenish the body's water and electrolyte levels after dehydration caused by exercise, excessive alcohol consumption, diaphoresis, diarrhea, vomiting, intoxication or starvation. Athletes exercising in extreme conditions (for three or more hours continuously e.g. marathon or triathlon) who do not consume electrolytes risk dehydration (or hyponatremia).

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