Should You Take Salt Before a Long Run?

Coarse and fine sea salts

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Your body needs sodium to regulate the amount of fluid in your blood and cells. That's not an issue for most people; they consume enough (or more than enough) through their diet. Runners, however, may be an exception. When you run, you lose electrolytes—including salt (sodium)—through sweat. If your sodium levels dip too low, you may retain excess fluid, which can have dangerous consequences.

This is a particular concern if you run long distances. You may already be familiar with a calling card of low electrolytes—muscle cramps. Replacing sodium and other electrolytes is especially important if you are running for more than 90 minutes.

Risks of Low Sodium Levels

Low sodium levels can lead to swollen fingers and toes, which may seem minor but are actually warnings of fluid imbalance. Not replacing the sodium you've lost and just drinking water can lead to hyponatremia, a low concentration of sodium in the blood that can be life-threatening if not treated. In severe cases, hyponatremia can result in seizures, coma, and even death.

Also known as water intoxication, this condition is the result of long periods of sweating, as well as excessive fluid intake. Symptoms of hyponatremia can include:

  • Muscle cramping
  • Confusion
  • Dizziness

Typical Sodium Requirements

The average American adult consumes more than 3,400 milligrams (mg) of sodium per day. However, the daily recommended allowance is 2,300 mg. Since many foods that people commonly eat every day (lunchmeat, cereals, bread, and snacks) all contain high levels of sodium, it can be easy to take in far more than the daily recommended amount.

Despite that, runners may still need to supplement their intake. Whether or not you need extra sodium before or during your run depends on how much salt you take in through diet and how much sodium you lose through sweat.

What Affects Your Sodium Needs

If you follow a low-sodium diet and have a high sodium concentration in your sweat, you will probably need to find a way to add extra salt before your run. Your individual needs come down to how much you sweat and the sodium concentration in that sweat. These can be affected by:

  • Weather: High temperatures lead to more sweat.
  • Activity level: Working harder makes you sweat more.
  • Physiology: Some people are just heavy sweaters or have saltier sweat.

Genetics are thought to have a significant role. Research shows that the sodium content in sweat can vary significantly from person to person. Among male professional athletes, the average sodium concentration in sweat was approximately 950 mg per liter, with a range from 350 mg to over 1,900 mg per liter.

If you are losing a lot of sodium through sweat, you may end up sweating off as much as 3,000 mg per hour.

The result of this sodium loss can create havoc with your body’s hydration levels, which means that restoring salt levels is critical. But if you are a runner who sweats less or isn't running as hard or as long, you may only lose a few hundred milligrams. In this case, you are less likely to need sodium supplementation.

Do You Need More Salt?

Taking a salt test can let you know how much sodium you need to consume to replace what your body has lost. But in most cases, you need to let your skin's appearance guide you. If you can see white lines of salt residue on your skin, you need a sports drink or a salty snack after your workout.

For most people, taking in about 200 mg of sodium after your workout will probably be enough to restore your levels. For distance and endurance runners, you will likely need to replenish your sodium levels mid-run.

If you find yourself sweating a great deal and begin to experience frequent muscle cramps, it is probably a sign you are getting low on sodium.

Ways to Replenish Sodium

There are several options for getting your sodium levels back up during a run or making sure they don't get too low ahead of time. What you choose to use really hinges on what's convenient and what you prefer.

Real Food Options

Some runners prefer to rely on real food options that provide a dose of salt as well as other nutrients. Some good options include:

  • Deli turkey: A one-ounce serving of deli turkey offers 250 mg of sodium and around 4 g of protein.
  • Salted almonds: A one-ounce serving provides around 96 mg of sodium as well as 6 g of protein.
  • Cheese: A single string cheese contains 210 mg of sodium as well as 8 g of protein.
  • Black olives: Eating just six olives can provide 200 mg of sodium.
  • Coconut water: One cup of coconut water contains a little over 250 mg of sodium. It is easily digested and contains other electrolytes lost through sweat including potassium, phosphorus, and magnesium.

You can also add some salt to pre-run meals. Sprinkle a little salt on your pasta, potatoes, or whatever carbohydrates you eat the night before a race. If you're having a smoothie for breakfast before a long run, add a pinch of salt to it.

Sports Drinks, Gels, and Chews

Sports drinks are specifically formulated to help you restore the electrolytes you lose when you sweat. Carbohydrate-rich sports gels and chews contain sodium and other nutrients that may be helpful during your run.

The amount of sodium in specific brands of these products can vary, so you should always check labels for nutritional information. Look for options that offer at least 100 mg of sodium per serving. However, if you have a sensitive stomach, you may prefer other options.

Salt Shots

A salt shot can be a good, handy alternative. If you're doing a run longer than two hours, you may want to take one before you begin, then another one halfway through your run/race. You will need a travel packet of table salt. Individual salt packets may vary, but the average serving size is approximately 0.5 g, which contains around 200 mg sodium. To do a salt shot:

  1. Empty the salt packet onto your hand.
  2. Lick the salt off your hand.
  3. Drink some water immediately after.

If you carry salt packets in a pocket or somewhere they may get wet from sweat, put them in a small zipper bag so they don't get soaked.

Another option is to take a salt tablet halfway through your long run. If you're running in a long distance race such as a half or full marathon, the medical aid stations will have salt packets, so you can always stop at an aid station for some extra salt if needed.

A Word From Verywell

Remember, you shouldn’t be experimenting with new foods or routines on race day. What you choose to use to replenish your sodium levels during a race should be the same items you use during your training, whether it's a sports drink, sports gels, a salty snack, or a salt shot or tablet.

4 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Agócs R, Sugár D, Szabó AJ. Is too much salt harmful? Yes. Pediatr Nephrol. 2019. doi:10.1007/s00467-019-04387-4

  2. Williams DM, Gallagher M, Handley J, Stephens JW. The clinical management of hyponatraemia. Postgrad Med J. 2016;92(1089):407-411. doi:10.1136/postgradmedj-2015-133740

  3. Centers for Disease Control and Prevention. Most Americans should consume less sodium.

  4. Ranchordas MK, Tiller NB, Ramchandani G, et al. Normative data on regional sweat-sodium concentrations of professional male team-sport athletes. J Int Soc Sports Nutr. 2017;14:40. doi:10.1186/s12970-017-0197-4

By Christine Luff, ACE-CPT
Christine Many Luff is a personal trainer, fitness nutrition specialist, and Road Runners Club of America Certified Coach.