Have you ever touched your face after a run, and it feels grainy? Or look down at your arms, and they are covered in white particles? Those are salt crystals!
While we run, our temperature rises, and our bodies need to work to cool off. We do this by sweating.
We sweat to keep us from overheating, but in turn, we lose essential electrolytes our bodies need to function properly.
That’s why it’s important to replenish both fluid and electrolytes during and after intense physical activity or in hot weather to maintain proper hydration and electrolyte balance for optimal performance.
What Are Electrolytes?
According to the National Library of Medicine,1National Library of Medicine – National Institutes of Health. (n.d.). Www.nlm.nih.gov. Retrieved June 3, 2024, from https://www.nlm.nih.gov/?_ga=2.248344513.798999400.1643050854-625113316.1641830008 electrolytes are “minerals in your body that have an electric charge. They are in your blood, urine, tissues, and other body fluids.”
The electrolytes found in our body are sodium, potassium, magnesium, chloride, phosphate, and calcium. We will discuss the most important ones for runners (in no particular order).
#1: Sodium
Sodium helps regulate proper fluid and electrolyte mineral balance so you don’t get dehydrated. It also assists with muscle contractions and nerve function.
#2: Potassium
Potassium is used in various vital bodily functions, such as regulating fluid and electrolyte balance, nerve signals, and muscle contractions. It also promotes glycogen storage and aids in the transportation of nutrients.
For us runners, if we don’t have enough potassium, it will be impossible for our muscles to properly contract, leading us to cramp up.
#3: Magnesium
Magnesium is used for energy production, metabolism, muscle and nerve contractions, muscle recovery, and general bone health.
It also helps avoid cramping.
Why Is Electrolyte Balance Important For Runners?
There is a common misconception that runners can stay sufficiently hydrated only with water.
Hydration isn’t just about replenishing fluid but also minerals. When we sweat, we expel not only water but heaps of crucial mineral electrolytes, too. That’s the grainy feeling on your skin that I mentioned before!
Specifically for runners’ needs, replenishing these electrolytes helps us avoid muscle cramping and fatigue, regulates our heartbeat, and keeps our body well-hydrated. As you can imagine, it also aids in performance.
If our body is functioning efficiently on a general-health daily basis, it will perform at its best while exercising as well. This is the goal.
Even a 2% decrease in body weight during exercise can result in impaired performance.2Latzka, W. A., & Montain, S. J. (1999). WATER AND ELECTROLYTE REQUIREMENTS FOR EXERCISE. Clinics in Sports Medicine, 18(3), 513–524. https://doi.org/10.1016/s0278-5919(05)70165-4
What Are The Consequences of Fluid and Electrolyte Depletion?
If you don’t consume enough electrolytes along with your fluid intake, you could not only experience the familiar runner repercussions such as cramping and stitches but any number of issues that can affect your health. These include:
- The body’s inability to regulate body temperature
- Confusion and poor decision making
- Dizziness
- Nausea
- Irregular heartbeat
- Fluid retention
- Dry mouth
- Gastrointestinal issues
These are some of the most common effects of dehydration, but we should also mention overhydration which is overhydrating without supplementing with the proper amount of electrolytes.
This overhydration results in a condition called hyponatremia, which can be very dangerous.
Hyponatremia
Hyponatremia3Clinical Journal of the American Society of Nephrology. (n.d.). Journals.lww.com. https://journals.lww.com/cjasn/Pages/default.aspx is the result of overhydration.
Here, the body’s sodium concentration in the blood dilutes and becomes too low. Without the proper amount of sodium, the body becomes unable to regulate the amount of water around the cells, which, in turn, causes them to swell.
This has been seen in runners in various marathons, especially when the weather is hotter than expected. In an attempt to stay hydrated, some drink in excess, which can provoke this condition.
Some of the signs of hyponatremia include nausea, vomiting, headache, confusion, fatigue, and muscle cramps. As you can see, most of these symptoms are also present in dehydration. If the case becomes more serious, it can result in seizures or a coma.
How Much Fluid Should Runners Drink During A Run To Stay Hydrated?
There is some new technology that actively measures your sweat and electrolyte loss in real-time, such as the Nix Hydration Biosensor. This patch is worn during exercise and sends live updates to an app to alert you of your hydration and electrolyte replacement needs.
This is a great tool for endurance athletes to stay on top of their fluid balance.
We may not all have access to this technology and may need to perform more of a DIY sweat test to get a ballpark number of how much we sweat per hour.
The Sweat Test: How To Calculate Fluid Loss
1. Weigh yourself with no clothes or shoes on.
2. Run for one hour at your race pace or training pace, ideally in the conditions in which you will race or often train. You want this data to be accurate for your daily training and/or race.
Note: During your run, do not consume or expel any liquid…so in simpler terms: no drinking or peeing! This will throw off your calculation. If you must drink water because of the weather conditions, you must take that into consideration when calculating your sweat rate, adding this fluid to the equation.
3. After your one-hour run, take off your shoes, clothes, and if necessary, wring out your sopping wet hair.
4. Weigh yourself again.
Now let’s calculate our results!
Take your pre-run weight and subtract your post-run weight. This weight loss will be your sweat loss per hour while you run. Let’s take a look at examples using kilos and pounds:
Kilos:
50 kilos (pre-run weight) – 48.5 kilos (post-run weight) = 1.5 kilos = 1.5 liters per hour
Pounds:
125 pounds (pre-run weight) – 122 pounds (post-run weight) = 3 pounds = 48 ounces per hour
The goal is to get as close as possible to replenishing your fluid loss while you run; however, 80% is a more reasonable goal if you are a heavy sweater.
Measuring Electrolyte Loss
If you can’t perform a lab test or something similar to calculate your electrolyte needs while running, trial and error can be another approach. And practice does make perfect.
Therefore, you should always practice hydration and take electrolyte supplements during your training runs to have a clear race day or general training strategy for when the heat and humidity peak.
There is a wide range of electrolyte products that you can try out, including electrolyte tablets such as Nuun, salt tablet chews like Saltstick, capsules, electrolyte powders, and electrolyte beverages and sports drinks such as Gatorade.
Also, most energy gels also contain electrolytes.
In addition, you can use this general recommendation as a guideline for running in the heat which is to consume 300-600 milligrams of sodium per hour during prolonged exercise.4University, U. S. (n.d.). Maintaining Hydration: A Guide for Endurance Runners. Extension.usu.edu. Retrieved June 3, 2024, from https://extension.usu.edu/nutrition/research/maintaining-hydration-a-guide-for-endurance-runners#:~:text=As%20a%20good%20rule%20of
However, this number can vary greatly depending on the individual’s sweat rate and running conditions. If you are a salty sweater, you could need additional sodium intake compared to a person who is not.
You’ll know you have found your balance when you do not experience cramping or other dehydration symptoms during a race, run, or intense exercise session. You’ll likely also see improvements in your performance and recovery.
To start, use sources of fluid and electrolytes such as sports hydration drinks during your next run for over an hour. This will help significantly replenish the electrolytes you are expelling when you sweat.
You can choose drinks with or without carbohydrates, depending on your needs.
Sports drinks that contain carbohydrates help to increase water absorption into the bloodstream. You also won’t have to consume as many products such as gels or gummies, as your sugar will be coming straight from your hydration.
If you try this out and are still cramping or feeling signs of dehydration, you may need to include additional sources of electrolytes, such as salt pills, into your regiment.
Most sports salt pill supplements contain sodium, potassium, calcium, and magnesium – precisely what we need to get back into our system.
Another option is to make your own DIY electrolyte drink by mixing together your favorite fruits and veggies that are high in electrolytes. Take a peek at this recipe!
Other Factors That Affect Fluid and Electrolyte Levels
There will be other factors that will affect the amount of fluid and electrolytes you will need, such as:
- Weather:5Oliveira, R. A., Sierra, A. P. R., Benetti, M., Ghorayeb, N., Sierra, C. A., Kiss, M. A. P. D. M., & Cury-Boaventura, M. F. (2017, December 21). Impact of Hot Environment on Fluid and Electrolyte Imbalance, Renal Damage, Hemolysis, and Immune Activation Postmarathon. Oxidative Medicine and Cellular Longevity. https://www.hindawi.com/journals/omcl/2017/9824192/ The hotter and more humid conditions you run in, the more you will sweat and, in turn, need to replenish with sources of electrolytes.
- Duration: The longer the run, the more you will need to replenish.
- If your run is 30 minutes, you can get away with drinking before and after and not during.
- If you are running between 30- 60 minutes, water should be just fine.
- If your run is over 60 minutes, it is a good idea to bring a sports drink or DIY electrolyte drink along to replenish during your workout.
- Intensity: The higher the intensity, the more you will sweat, and the more you will need to replenish your fluid and electrolytes.
5 Tips For Keeping A Good fluid And electrolyte balance
#1: Hydrate Regularly
Don’t just think about hydration when working out, but as a constant in your day-to-day life. Most of us will be able to count on 2 liters of water a day to ensure proper hydration, but some may need to add extra electrolytes to that fluid depending on specific needs.
Always carry your water bottle with you so you sip throughout the day.
#2: Hydrate Before You Run
Add around 500 ml of fluid to your pre-run snack about two hours before your run. Make it fruit juice for some added carbs and kill two birds with one stone!
#3: Hydrate During Your Runs
If your run is longer than 60 minutes, be sure and replenish 80% of your average fluid loss while running. This is especially important for high-intensity workouts, long distance runs, and races.
#4: Replenish Your Fluid and Electrolytes After Your Runs
Just because you drank before and during doesn’t mean you stop there. Rehydration is also key.
Replenish after your runs with a recovery drink, including the all-important electrolytes discussed. An all-around recovery will also include protein and carbohydrates to give you a complete restoration.
#5: Eat a Well-Balanced Diet
Eating a well-balanced diet, including water and electrolyte-filled foods, can help replenish needed fluid and electrolytes in the body. Let’s take a look at some great options:
- Fruit: Watermelon, strawberries, cantaloupe, peaches, and tomatoes
- Veggies: Cucumber, lettuce, spinach, kale, celery, zucchini, cauliflower and broccoli
- Other: Soup, broth, and skim milk
From our daily hydration to our running-specific strategies, we need to take care of these details for the sake of our performance and, more importantly, our health.
For even more information on hydration, check out this next guide:
Hello,
Thanks for the great article and content in general.
I just have one note I noticed:
50 kilos (pre-run weight) – 49.5 kilos (post-run weight) = 1.5 kilos
where 1.5 should in fact be 0.5 because 50 – 49.5 = 0.5.
Have a great day and keep running!
BR,
Martin
Thanks Martin!!! Adjusted so the post-run weight is 48.5kg, now the maths flow 🙂
Thomas from Marathon Handbook