It’s the golden era of electrolytes. But do you need special products or just a balanced (and salty) diet?
(Photo: Getty)
Published September 2, 2025 03:47PM
Is it just me, or are electrolytes having their day in the sun? The volume of electrolyte-laced drinks and powders marketed toward active people is staggering. Heck, you can even find electrolyte-infused coffee and non-alcoholic beer geared toward hard-charging athletes. One needs to ponder whether we have hit peak electrolytes.
But do you even need to supplement with electrolytes to run your best? Can faster times, fewer cramps, and bonk-free runs be had by simply hydrating with more electrolytes? A recent piece in the New York Times questions the value of electrolyte-containing products, going so far as to claim they are a rather useless supplement, regardless of the length and intensity of sporting activity. Yes, electrolytes remain one of the most debatable topics for endurance athletes. While some believe relying on plain water, even if incredibly boring, is all that is needed, many others argue that electrolyte products provide the platform for optimal performance and health.
Which begs the question: How savvy are you about electrolytes and their role in everyday health and athletic function? Below, we break down everything you need to know about electrolytes for runners.
Electrolytes Explained
In short, electrolytes can be considered the power lines of our bodies—they are positive or negatively charged ions that conduct electrical signals used to maintain fluid balance, allow for efficient muscular contraction, regulate pH levels and nerve function, and keep our neurons firing as they should. “Electrolytes can help draw fluids into the body and can help with thermoregulation during hot runs,” Kylee Van Horn, a registered dietitian, running coach, and the founder of FlyNutrition in Carbondale, Colorado, says. So, yes, it’s important that we maintain a proper electrolyte balance.
The main electrolytes are:
- Sodium
- Potassium
- Magnesium
- Calcium
- Chloride
You can source these electrolytes from a wide variety of foods. Pumpkin seeds and whole grains give you magnesium. Of course, yogurt and milk dish up calcium. Not just bananas, but everything from sweet potato to kale to avocado has an abundance of potassium. And anything packaged or on restaurant menus is seemingly laced with sodium.
How Do You Lose Electrolytes?
Our bodies very carefully regulate electrolyte balance—healthy kidneys are equipped to keep or eliminate electrolytes as needed to maintain a proper equilibrium. But here is the catch—when you add exercise to the equation, you can lose varying amounts of them in your sweat. “Sweating more causes more fluid loss, and electrolytes follow this fluid,” Van Horn says. So it makes sense that electrolyte products are marketed to endurance athletes to help them offset what is shed during sweat-inducing workouts.
Are Electrolyte Losses and Needs Equal Across the Board?
Definitely not. Sodium makes up the majority of electrolytes lost in sweat—up to 80 to 90%—and is arguably the most crucial to replace. If you’ve ever finished a big run and noticed your shirt covered in white crusties, that’s sodium left behind. Because it’s so highly concentrated in sweat, sodium is the electrolyte most likely to dip below equilibrium during exercise. The harder and longer you go, the more sodium you’ll lose.
But sodium isn’t the only electrolyte in your perspiration. Magnesium, chloride, potassium, and calcium are also present, though in much smaller amounts. “Sodium is lost in hundreds to thousands of milligrams per liter of sweat, while electrolytes like magnesium and calcium are lost in the tens of milligrams per liter,” Van Horn explains. That’s why you need to worry less about replacing those other electrolytes compared to sodium.
So, Do You Need to Supplement With Electrolytes?
The answer, like so many things in running, is: It’s individual.
“Electrolyte replacement during exercise depends on several factors, including personal sweat concentrations, duration and intensity of exercise, weather, altitude, hydration, and electrolyte status going into a training session,” Van Horn says. What’s clear, though, is that athletes should mainly zero in on sodium, the electrolyte lost in the greatest quantities.
Taking in sodium during exercise can not only help offset losses, Van Horn stresses that it will go a long way in reducing the risk for hyponatremia, a potentially life-threatening condition where sodium levels in the blood become dangerously low as a result of drinking copious amounts of sodium-poor fluids. When this happens, the body’s water levels rise, and cells begin to swell. This swelling can cause many problems, from cognitive issues to muscle weakness to vomiting to even death in rare cases.
The American College of Sports Medicine (ACSM) recommends some degree of sodium intake during exercise when sweat rates are high (>1.2 L/h), if someone is a “salty sweater,” and during prolonged exercise lasting greater than 2 hours.
However, some research suggests longer training distances, lower body mass, avoidance of overhydration, and exercising in cooler temps are just as crucial, if not more, to keeping sodium levels in balance than supplementing with electrolytes.
It’s also worth remembering that including some sodium in your bottle can increase your drive to drink, which helps with hydration efforts. That’s a win in my books.
What About the Other Electrolytes?
There has yet to be any solid research published demonstrating that consuming electrolytes other than sodium during endurance exercise has an impact on health or performance. That makes sense considering how little magnesium, potassium, and calcium we lose in sweat in comparison to sodium. “However, if someone is a very heavy sweater, has low calcium and magnesium intake in their daily diet already, or if they are doing ultra-endurance events, supplementing with these could be a consideration,” Van Horn says.
In short, sodium intake should be your priority, and consuming additional electrolytes can be viewed as an insurance policy toward optimizing your diet and workouts.
Watch the Clock
If you’re out for just a leisurely run lasting less than an hour, Van Horn says your electrolyte stores should be adequate, making the need for supplementation unnecessary for most. Here, let plain agua quench your thirst and don’t fret if you haven’t poured a salty powder into your bidon. “Replacing a certain amount of sodium losses becomes more of a need when you push past the 60-minute mark, particularly if you’re sweating heavily.” The longer, harder you go, the more you’ll want to consider spiking your hydration with sodium, and probably some carbs.
An array of the electrolyte supplements currently on the market. (Photo: RUN Editors)
How Much Sodium Do You Need During Runs?
Sweat production (and therefore sodium loss) is influenced by various factors, including environmental conditions such as humidity, exercise duration and intensity, genetics, and clothing. A less fit runner will lose more electrolytes than an avid runner who’s more efficient at maintaining electrolyte homeostasis. That makes nailing down a universal electrolyte recommendation no easy task.
On the whole, most athletes lose 500 to 1,000 mg of sodium per hour of activity. (If you are a larger runner, heavy sweater, or racing in humid climates, losses can be greater.) For this reason, Van Horn recommends getting 500 to 800 mg of sodium for each liter of fluid consumed. Just know that many bottled sports drinks don’t reach this mark.
A recent review of studies published in the International Journal of Environmental Research and Public Health, looking at endurance and ultra-endurance athletes, suggests that during long-distance exercise, it’s advisable to take in 500–700 mg of sodium per liter of fluid to adequately lower the risk of developing hyponatremia. When the sweat rate is elevated in hot conditions, endurance athletes should aim for at least 300–600 mg of sodium for each hour of activity.
According to other research, a sports drink product that supplies sodium in the range of 230–690 mg/L results in optimal fluid absorption and prevention of hyponatremia. For the most part, this is a concentration of sodium you can get from making a drink using some of the powdered and tablet electrolyte products on the market. Don’t forget that other sports nutrition products like gels and chews can contribute some extra sodium. If you often finish runs looking like a ballpark pretzel, you might require an even bigger dose of sodium.
For the most precise answer to your electrolyte needs, you can turn to an increasing number of companies like Nix. You may learn that you lose more or less sodium in your sweat when running than you thought.
Can Sodium Make You a Better Runner?
The amount of evidence regarding performance benefits from sodium supplementation is rather small. One 2015 double-blind study in the Scandinavian Journal of Medicine & Science in Sports found that runners who supplemented with salt (sodium chloride) and other electrolytes in addition to consuming a sports drink before and during a half-Ironman improved race times by an average of 26 minutes and experienced less of a drop in body weight compared to those who took a placebo.
The biggest performance boost came during the later parts of the race, including the run segment when sodium levels are more likely to be at their lowest. The scientists also reported that salt supplementation worked to stimulate thirst, which encouraged subjects to drink more and, in turn, maintain better hydration status.
“Sodium does help with thermoregulation, which can help with plasma volume and cardiac output during exercise,” Van Horn explains. “So without it, paces can slow and running can feel a lot harder.”
But on the whole, we need more evidence to show that sodium supplementation is critical to performance. That doesn’t mean you should push it aside, just that there’s no proof it’s crucial for PR pursuits.
Consider Your Post-run Needs
Some data suggests chugging gallons of water after a sweaty run may not be the best strategy for replenishing electrolyte levels. (This isn’t particularly surprising.) Extra electrolytes can also encourage better fluid retention, thereby improving rehydration.
“If someone doesn’t eat a lot of sodium-containing foods and a varied diet, it could be challenging to replenish exercise losses without a supplement,” Van Horn explains. “However, eating some salty foods or salting your meals can be used to help replenish after exercise.”
So if you just finished a workout sweating buckets, you have permission to reach for salty, crunchy snacks like pretzels and nuts. But if your run was rather breezy without generating much sweat, there is no pressing need to reach for the salt. I’ve yet to see any convincing evidence that the majority of endurance athletes can’t get all the daily electrolytes they need by consuming a varied, whole-food diet, especially if they’re giving themselves enough recovery time.
Wait, Isn’t Consuming Too Much Sodium a Health Hazard?
This is where things get a bit tricky. Certainly, most of the general public consumes too much sodium, which is a contributing factor to cardiovascular disease. Dedicated runners, however, should be able to get away with being more generous with their sodium intake. The more sodium you lose during workouts, the more you can include in your diet. Consider that a little bit more motivation to lace up your shoes. But if you are getting most of your sodium from ultra-processed foods, that is a different matter.
There is, however, a limit to using electrolytes during workouts. “Oversupplementing with electrolytes can lead to several issues, including nausea, vomiting and diarrhea, headaches, and confusion,” Van Horn cautions. “And if too many electrolytes are consumed without being accompanied by sufficient fluids, it can lead to dehydration and worsen symptoms.” Taking in high amounts of sodium while letting yourself get too dehydrated can lead to swelling caused by water retention.
Can Electrolytes Prevent Muscle Cramps?
If only it were that simple. There is no convincing evidence that using an electrolyte product during a run will prevent painful cramps from occurring. “Electrolyte products may help with muscle cramps, but muscle cramping can be due to multiple other factors,” Van Horn says, explaining that poor training and muscle fatigue are often the culprits.
Research in the Journal of Strength and Conditioning Research found that marathon runners who suffered exercise-induced muscle cramps during the race did not have greater levels of dehydration and electrolyte depletion after the run than those who did not endure the pain, but they did have significantly higher concentrations of muscle damage biomarkers. No amount of sodium will help if your quads are screaming because they are overworked.
So Do Runners Need Electrolyte-Rich Beverages?
Aside from the cost, there appears to be little downside to runners consuming electrolyte products. The biggest potential upside comes from taking in extra sodium during bigger efforts. But, typically, it’s not as hard as you might be led to believe to get enough electrolytes from your diet. Now, where is that banana and bag of salted peanuts?