Electrolytes are minerals in your body that carry electrical charges. They play a vital role in maintaining proper fluid balance, nerve function, and muscle contraction, making them essential for active individuals. Electrolytes help make muscles contract by promoting the transmission of messages across nerve cell membranes. Electrolyte balance is critical to optimal performance and overall health. The two chief electrolytes are sodium and potassium. Sodium regulates performance outside cells, whereas potassium regulates performance inside cells.