| What they are | Charged minerals (sodium, potassium, etc.) |
| Lost via | Sweat (especially sodium) |
| Replace with | Drinks, tablets, salty food |
| Help prevent | Cramping & hyponatremia |
Electrolytes are minerals — chiefly sodium, plus potassium, magnesium, and chloride — that are essential for fluid balance, nerve signaling, and muscle function. Runners lose them (especially sodium) through sweat, so replacing electrolytes during long or hot efforts via drinks, tablets, or food helps maintain performance and helps prevent both cramping and the overhydration condition hyponatremia.
Balance your fluids
Replacing them — not just drinking water — guards against hyponatremia and dehydration; often taken with a gel.
Frequently asked questions
What are electrolytes?
Electrolytes are minerals that carry an electrical charge and are vital for body functions like fluid balance, nerve impulses, and muscle contractions. The main ones relevant to runners are sodium, potassium, magnesium, and chloride. You lose them through sweat, with sodium being the most significant loss during exercise.
Why do runners need electrolytes?
During long or hot efforts, sweating depletes electrolytes (especially sodium), which can impair performance and contribute to muscle cramping. Replacing them — alongside fluids and carbohydrates — helps maintain energy and muscle function. Crucially, replacing sodium also helps prevent hyponatremia, a dangerous dilution of blood sodium from drinking too much plain water.
How do you replace electrolytes while running?
Through electrolyte drink mixes, salt or electrolyte tablets/capsules, electrolyte-containing gels and chews, or salty foods, matched to how much and how salty you sweat and how long and hot the effort is. Practice your strategy in training, and balance electrolytes with fluids and carbs rather than relying on plain water alone for long events.
Sources
- Electrolytes & hydration — American Council on Exercise
- Hydration safety — Wilderness Medical Society