Electrolytes play many roles in the body, but runners associate them most with fluid balance, hydration, and muscle function. Without adequate electrolyte balance, a runner’s workout will indeed suffer. With the right mix of these electrically charged minerals, our running systems are good to go!
The four major electrolytes runners have likely heard about, and know to focus on, are sodium, potassium, calcium, and magnesium. Chloride is another electrolyte that is often overlooked, but replaced easily if adequate salt (sodium chloride) is consumed throughout the day. Electrolytes are not only lost through sweat, but also blood, urine, and feces. The latter is important for runners to consider, as most of us have experienced race-day, well, unpleasantries in the port-a-potties.
During my first marathon, I learned first-hand just how much power electrolytes had over my body and running performance — and just how much I still had to learn about both fueling and re-hydrating. On a hot March day, after a snow-packed winter training cycle, I spent approximately four hours trying to take in enough fluid and food to make up for all the electrolytes I was losing as I sweat through the streets of Washington DC. My nutrition and hydration needs felt so different that day compared to on my cold winter training runs, and my body and performance suffered as a result.
These are a few signs of electrolyte depletion (or imbalance):
- – Muscle spasms
- – Weakness
- – Dizziness
- – Blood pressure changes
- – Dark urine (a sign of dehydration)
- – Nausea
- – Constipation
Electrolytes are more often associated with hydration than food, since one of their primary roles is in maintaining fluid balance. Yet plenty of natural foods offer a balance of electrolytes that can help runners replace losses. Adding electrolyte-rich foods to a daily mix of hydration and fueling efforts reduces the need to rely on high-sugar drinks or supplements to maintain a healthy electrolyte balance.
Food Sources of Electrolytes
Sodium (and Sodium Chloride)
Sodium chloride, otherwise known as table salt, can get a little bit of a bad rep. If you have medical needs to reduce or manage salt intake, consult with a primary care physician and sports dietitian prior to changing your salt intake. Sodium and chloride are essential to maintaining fluid levels, helping your body stay hydrated. That said, sodium needs vary widely among runners, especially considering everyone’s sweat rate and sweat composition are different. Runners with high sweat rates, or salty sweat (that white crystal film that you see on shirts, hats, shorts, and sometimes your skin after a run), likely have higher sodium needs.
Processed food and restaurant foods are probably contributing the majority of your sodium chloride intake. Some examples: soups, deli meats, fast food (including fast casual) and snack foods (pretzels, chips, crackers) are typically high in sodium chloride. Canned vegetables, seasoning mixes and sport-specific foods (e.g. chews, GU, shot bloks, etc.) are additional sources. And of course, salting your foods is an obvious contribution to sodium chloride intake. On the contrary, fruits and vegetables are naturally low in sodium.
Potassium works with sodium (and chloride) to help maintain fluid balance. Plenty of foods contribute to daily potassium intake, including some of these great sources:
- Fruits: apricots, avocados, bananas, cantaloupe, dates, nectarines and oranges
- Vegetables: artichokes, beets, brussels sprouts, parsnips, potatoes, pumpkin, spinach, sweet potatoes, swiss chard and tomatoes
- Nuts: Almonds, walnuts and pecans
Calcium has many roles, but as an electrolyte it helps with muscle contraction and helps heart function. Dairy products are an excellent source of calcium, as well as vitamin D, which helps with calcium absorption. If you can tolerate dairy, consuming yogurt, cheese and other cream-based products is a great way to get your fill. But plenty of other foods provide calcium, too.
Here are some of the best non-dairy food sources that are rich in calcium:
- Vegetables and legumes: cooked collard and turnip greens, cooked kale, black-eyed peas, baked beans, iceberg lettuce and green peas
- Misc: Canned salmon, almonds, soy products (e.g. edamame, tofu, and soy milk) and fortified non-dairy beverages such as nut milks and orange juice
Magnesium helps with muscle function and protein synthesis, and it has a role in the transportation of calcium and potassium across cell membranes. It is found in a variety of foods but can be hard to identify, as it isn’t a required listing on the Nutrition Facts Label.
One serving of each food in this list provides 10 to 20 percent of the recommended daily value of magnesium:
- Yogurt, rice, baked potato, avocado, whole wheat bread, peanut butter, edamame, black beans, soy milk, peanuts, cashews, pecans, walnuts and almonds
Including all of the foods listed above in your daily or weekly eats will help ensure your electrolytes stay balanced. If you want to get creative, these recipes made by registered dietitians should be added to your rotation of pre- and post-run meals and snacks.
Strawberry Patch Smoothie, by Dana McDonald
- High in potassium and calcium
Kelly Green Power Smoothie, by Kelly Jones
- Good source of magnesium and calcium, with 10 percent of daily sodium and potassium
(Vegan) Energy-boosting Smoothie, by Kara Lydon
- High in calcium, magnesium, and potassium
Apricot chicken, by Joy Bauer
- Good source of potassium and sodium
Tofu vegetable stir-fry, by Debbie Murphy
- Good source calcium and sodium
Black-eyed pea and brown rice veggie burger, by Karman Meyer
- High in magnesium and calcium
Orange-glazed brussels sprouts and sweet potatoes, by Amanda Hernandez
- Excellent source of potassium
Chocolate peanut butter smoothie bowl, by Deanna Segrave-Daly
- Good source of potassium, calcium and magnesium
Dark chocolate avocado mousse, by McKel Hill
- HIgh in potassium, magnesium, and calcium
Nutty protein granola bars, by Anne Mauney
- Excellent source of magnesium and a good dose of potassium
For more information on each electrolyte, its functions and best food sources, visit and search the National Institutes of Health Office of Dietary Supplements’ site: ods.od.nih.gov/