Potassium enters the cell more readily than does sodium and instigates the brief sodium-potassium exchange across the cell membranes. In the nerve cells, this sodium-potassium flux generates the electrical potential that aids the conduction of nerve impulses. When potassium leaves the cell, it changes the membrane potential and allows the nerve impulse to progress. Another of the pump's most important functions is preventing the swelling of cells. If sodium is not pumped out, water accumulates within the cell causing it to swell and ultimately burst.
Potassium is important for normal growth and for building muscle.
Though sodium is readily conserved by the body, there is no effective method for potassium conservation. Even when a potassium shortage exists, the kidneys continue to excrete it. Because the human body relies on potassium balance for a regularly contracting heart and a healthy nervous system, it is essential to strive for this electrolyte's balance. In medicine, potassium is one of the most commonly prescribed minerals. It is also commonly measured in biochemical testing and is supplemented if it is low.