Although sugar is often found in sports drinks and other electrolyte replacement products, it is not an electrolyte. Electrolytes include sodium, potassium, chloride and bicarbonate.
Vigorous exercise, dehydration and some medical conditions can cause the body to lose both sodium and potassium, throwing the electrolyte balance out of balance. Since electrolytes need to be in balance for the body to conduct electrical impulses, this can result in various medical problems including fatigue, weakness, confusion and muscle spasms.
Sugary drinks or snacks provide carbohydrates, but do nothing to bring electrolyte levels back into balance. Drinks containing electrolytes can help replenish the body.