What Runners Need to Know – The Importance of Electrolytes and the Best Ways to Stay Hydrated Before, During, and After Treadmill Runs

Have you ever wondered why your dog likes to lick your sweaty face after a run? The answer of course is salt, which is one of the body’s essential minerals it loses while sweating. The term electrolyte broadly includes all of these. Technically speaking, an electrolyte is a substance that conducts electricity via the movement of ions instead of electrons. The list of electrolytes includes most soluble salts, acids, and bases when dissolved in water. Nutritionally, you’d recognize this list as including sodium, potassium, chloride, calcium, magnesium, and phosphates.

So when sweating, these pour out of your body along with all your hydration. Low levels of electrolytes are the reason you feel run-down and can result in dehydration. One of the functions these minerals serve is to prevent dehydration. They also assist in proper muscle contraction, blood pressure, and nerve signaling. If you’ve ever experienced severe cramping during a run, or begun to feel foggy enough to black out, this is an indicator you’re low on electrolytes. Other symptoms include nausea, bloating, and dizziness.

Hard training and competitions require proper nutrition, and a special consideration of electrolyte levels. Photo by Brian Boyce

How Many Electrolytes Do You Lose Running?

Studies affirm that the volume of electrolytes lost during exercise varies from person to person, and in my experience, the weather plays a role. If I’m running outside during the summer I tend to sweat more profusely than in wintertime. If you’re really curious, you can always get your physician to order a sweat test, but keep in mind that an endurance athlete can lose between 11-12% of their body weight in the form of sweat during a 12.3-hour Ironman triathlon in a cool environment, and day-long walking in the desert can result in 14-18% loss.

So, the average runner may sweat out between 400 and 2,400ml per hour of exercise, and the sodium content of that liquid will vary depending on your own diet and build, anywhere from 115mg to 2,000mg. What this means is that hydration is essential during exercise, because there’s really no way to predict how many electrolytes you’ll lose while running.

How Do I Replace Electrolytes?

There’s lots of options, from drinks specifically designed to do this, to salt tablets, to various kinds of food. Most of these commercial options contain between 250-300mg of sodium per serving, and you can check the nutrient label for potassium and other essential minerals.

So right off the bat, I’m going to prepare differently for a 5k race than a Strongman Competition or bodybuilding show, and certainly a marathon. But irrespective of the activity and conditions, you should prepare in a three-stage process: Before the run, during the run, and after the run.

Even a day before the competition, make sure your body is well-hydrated and stocked with electrolyte-heavy foods and liquids. When competing in a bodybuilding show, wrestling match, or any weight class competition, this can be an issue as people try to dehydrate themselves to make weight. If you’ve been doing this, or have lost weight recently, be mindful of the necessary minerals before the competition.

During the competition, drink electrolyte-heavy fluids as needed. During 5ks and marathons, you’ll see the runners grabbing bottles of sports drinks and water along the way. This is why.

After the competition, you’ll want to replace the electrolytes you’ve lost. One of distance runners’ favorite go-to’s is chocolate milk.

Weather conditions play a role in how many electrolytes you’ll lose in a day. Photo by Brian Boyce

List of Electrolyte-Heavy Drinks and Foods

If you’re looking to prep for a competition, below are some suggested items you could throw into the mix to help with your electrolyte levels.

Whether you’re running for fun or training for a hard competition, keep proper hydration in mind always. Fueling your body with electrolytes is essential if your efforts are going to result in success. At any point during an event if you’re feeling run down, don’t be afraid to grab a sports drink or good old fashioned H2O.