Electrolytes are crucial for our body to transmit nerve impulses and contract muscles and help with water balance as well. The electrolytes that are needed for these functions include sodium, chloride, potassium, magnesium and calcium.
Electrolytes are lost through from the body through sweat, so it is important to replace them. The more you sweat the more electrolytes you lose. If you are caked in salt after runs or sweat a lot during runs, you are probably losing a fair amount of electrolytes during your workouts and should take care to replace them.
Symptoms? Watch out for muscle cramping, abdominal cramping, light-headedness, nausea, confusion, and muscle spasms. When you are working out hard enough to sweat a lot, try to drink 1 cup of water every 15 minutes. If the longs are run, consider drinking a sports drink.
Ultimately, the best electrolyte replacement is one that you prefer and follow. Remember that both water and electrolytes are lost during workouts and should be replenished.