Reading Time: 6 minutes
What are electrolytes and are they important? What happens to them when you exercise? How do you replenish electrolyte levels?
When training clients, we tend to place a lot of focus on the three macros—carbs, protein, and fat. But creating a diet that fully supports physical activity (and health) is more in-depth. It also involves ensuring that clients get the micronutrients their body needs. This helps them to function optimally. Enter the electrolyte.
Electrolytes are minerals that get electrically charged (positive or negative charge) when dissolved in liquid. They are essential for many important body functions. They are most known to start nerve impulses, aid with muscle contraction, and help balance fluid within the body.
The seven most common electrolytes in the human body are:
Add a fluid (like water) to an electrolyte and it sparks an electrical impulse. This impulse helps regulate several bodily functions important to health and wellness.
If you have each electrolyte in the amount you need, you are said to have an electrolyte balance. Electrolyte balance is important for helping the body with these essential functions:
Muscle contraction: Bodies move via muscle contraction. Electrolytes (specifically calcium and magnesium) help trigger the muscle contraction process (1). Without them, your muscles wouldn't contract or allow you to move. And, this process includes contraction of the heart muscle and its ability to beat.
Fluid balance: Your body is made of mostly water. It is used in the respiratory process when you breathe, to digest your food, to regulate your temperature, and many other body functions. Your organs, tissues, and cells need appropriate fluid balance to function properly. The number of electrolytes in your blood can trigger your kidneys to excrete less water (during dehydration) so more water stays in the blood.
Conducting nerve impulses: Your brain is Your control center and is constantly sending messages to different parts of the body. When electrons move across the membrane of the cell, they act like a little light switch that triggers a chain reaction of nerve impulses (2).
Even though various electrolytes support different roles within the body, they all work together to help your body function, perform, and feel its best. And the functions they support are not just important for exercise, but they also are important for daily life.
For example, sodium is important for maintaining healthy fluid levels. Magnesium is critical for muscle and nerve function. Bicarbonate assists with blood pH balance. Calcium helps stabilize blood pressure. Potassium supports heart, nerve, and muscle function. Chloride regulates blood pressure. Phosphate aids in muscle and nerve function.
Typically, the most important factor in regard to electrolyte loss during exercise is the amount of sweat lost. The body is constantly working to regulate itself. As your client sweats during exercise, not only do they lose some of the fluid in their body, but they also lose many of the electrolytes working to keep the body hydrated and balanced. So, usually, the more a person sweats during exercise, the more electrolytes they tend to lose.
Many factors contribute to water and electrolyte loss. But keep in mind, the actual number of electrolytes lost varies for each individual (3) and excessive sweating from exercise isn't the only contributor to fluid and electrolyte loss.
Exercising in hot or humid weather
High intensity workouts
Long durations of physical activity (typically longer than 60-90 minutes)
Improper clothing that isn't breathable
Spending significant time outside in hot or humid weather (not exercising)
In a person that naturally sweats excessively
So, it's important to understand that the average person who works out for 60 minutes or less, in cooler weather, and loses an average amount of sweat is losing electrolytes but likely nothing to be highly concerned with. On the flip side, clients who are performing for long periods of time, are in hot weather, or tend to sweat more should be more concerned with their electrolyte loss. It is, however, important in both scenarios that the clients are staying hydrated with water.
Electrolyte imbalance can occur if your levels of these minerals are too high (electrolyte excess). An imbalance can also exist if they are too low (electrolyte deficiency). When your electrolyte level is off, it can cause a variety of health issues.
The Cleveland Clinic warns that a major electrolyte imbalance can affect a person both mentally and physically (4). In cases of severe imbalance, it may even lead to coma, seizures, and cardiac arrest. So, keeping levels where they need to be is important to prevent these types of effects.
How do you know if your electrolytes are off-kilter? Electrolyte imbalances can show up in the form of:
muscle cramps, spasms, or weakness
nausea or vomiting
diarrhea or constipation
fast or irregular heartbeat
numbness or tingling in the extremities
The only way to know for sure if you have an imbalance is with a blood test. If there is a major imbalance, IV fluids, medications, or hemodialysis may be needed. In cases of minor imbalances, certain foods can help support electrolyte replenishment.
Many consumers tend to think that replenishing electrolytes and water in the body means drinking a sports drink. But, the human body makes some electrolytes and you can replenish electrolytes by eating more high-mineral foods. Here are several food sources good for increasing electrolyte levels.
Beans and Legumes
Nuts and Seeds
Meat and Meat Alternatives
Other Foods that are a Good Source of Electrolytes
Drinking certain beverages can also help with electrolyte replacement. One benefit of an electrolyte drink is that it’s easy to grab. That makes it a good solution, especially when you need to replenish your electrolytes quickly but don’t have access to food.
Beverages that can help restore electrolyte levels include:
tap or bottled water with lemon juice
fruit juice (just watch out for added sugar)
If your clients’ workouts are 60 minutes or longer, have them consume a sports drink or one of these other beverages. This can help keep their electrolytes where they need to be. These fluids can also be beneficial if electrolytes are lost due to being sick or having the flu.
Some promote supplements as a way to restore electrolyte balance. You can purchase electrolyte tablets, capsules, powders, and more. But do they work?
One2022 study says found that, when combined with creatine, an electrolyte supplement helped improve sprint cycling performance (5). This dual supplement increased the subjects’ peak power by 4%. It also improved their overall mean power by 5%. Subjects receiving a placebo had no such improvements.
Electrolyte supplements may also be helpful with injury recovery. That’s what was reported in a study involving 94 older adults with a knee replacement (6). Subjects receiving an electrolyte-carbohydrate supplement had greater comfort levels. They reported less pain, anxiety, and hunger than those not receiving the supplement.
Foods, beverages, and supplements can each be a real simple way to correct minor electrolyte imbalances. That’s in addition to the natural electrolytes that the body creates itself. In cases of major imbalances, a supplement may be recommended. A dietitian or the client’s healthcare provider can advise the best approach based on the level of imbalance and its suspected cause.
Reinforcing the importance of staying hydrated can help your clients’ electrolytes stay balanced. Encourage them to drink fluids before, during, and after exercise sessions. For shorter or less intense workout sessions, water can do the trick. When exercise is prolonged, intense, or performed in a hot environment, consuming foods and drinks high in electrolytes may be a better approach.
You can help clients keep their electrolyte levels in check as an ISSA Certified Nutritionist. This certification teaches you how to create personalized meal plans for your training clients. This can help them achieve their fitness goals and enjoy the health benefits that come with an active lifestyle.
By becoming an ISSA Nutritionist, you'll learn the foundations of how food fuels the body, plus step by step methods for implementing a healthy eating plan into clients' lifestyles.
Sweeney, H. L., & Hammers, D. W. (2018). Muscle contraction. Cold Spring Harbor Perspectives in Biology, 10(2). https://doi.org/10.1101/cshperspect.a023200
Lodish H, Berk A, Zipursky SL, et al. Molecular Cell Biology. 4th edition. New York: W. H. Freeman; 2000. Section 21.2, The Action Potential and Conduction of Electric Impulses.
Lara, B., Gallo-Salazar, C., Puente, C., Areces, F., Salinero, J. J., & Del Coso, J. (2016). Interindividual variability in sweat electrolyte concentration in marathoners. Journal of the International Society of Sports Nutrition, 13, 31. https://doi.org/10.1186/s12970-016-0141-z
Electrolyte imbalance: Types, symptoms, causes & treatment. Cleveland Clinic. (n.d.). Retrieved March 8, 2023, from https://my.clevelandclinic.org/health/symptoms/24019-electrolyte-imbalance
Crisafulli, D. L., Buddhadev, H. H., Brilla, L. R., Chalmers, G. R., Suprak, D. N., & San Juan, J. G. (2018). Creatine-electrolyte supplementation improves repeated sprint cycling performance: A double blind randomized control study. Journal of the International Society of Sports Nutrition, 15(1). https://doi.org/10.1186/s12970-018-0226-y
He, Y., Tang, X., Ning, N., Chen, J., Li, P., & Kang, P. (2022). Effects of preoperative oral electrolyte‐carbohydrate nutrition supplement on postoperative outcomes in elderly patients receiving total knee arthroplasty: A prospective randomized controlled trial. Orthopaedic Surgery, 14(10), 2535–2544. https://doi.org/10.1111/os.13424