Electrolytes and Exercise: Keeping Your Body Balanced

What are electrolytes and are they important? What happens to them when you exercise? How do you replenish electrolyte levels?

Have your clients ever asked you these questions? Do you know what to tell them?

This article will address those questions so you are better equipped to help guide your clients with the appropriate information.

What Are Electrolytes?

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.

Five Most Common Electrolytes:

• Chloride - Helps support the balance of fluids on the inside and outside of cells within the body

• Potassium - Aids in nerve impulse conduction, muscle contraction, and heartbeat regulation

• Calcium - Supports muscle contraction and helps regulate heartbeat

• Sodium - Helps maintain fluid balance within the body

• Magnesium - Vital in many different chemical reactions within the body (regulating heart rate, supporting muscle contraction, conduction of nerve impulses, and more)

Why Are Electrolytes Important?

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.

Electrolytes Support 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).

What Happens to Electrolytes When You Exercise?

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.

Factors Contributing to Water and Electrolyte Loss During Exercise

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.

Exercise Conditions:

• 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

Individual Considerations:

• Age

• Gender

• Hydration status

• Diet

• Body size/composition

Other Factors:

• Vomiting

• Diarrhea

• 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.

What Happens When the Body is Low on Electrolytes?

Much like many other compounds in the human body, electrolytes need to stay within a certain range for proper health and function throughout the body. If a person loses too many electrolytes, they may start to experience a variety of negative symptoms. An individual may have one or several of the following:

• Muscle cramping

• Headaches

• Muscle weakness

• Irregular heartbeat

• Dizziness/confusion

• Appetite loss

• And, in serious cases, seizure or death

If the electrolyte imbalance is mild, a client may or may not experience any symptoms. If a client is experiencing any of the above symptoms and there is suspicion of an electrolyte disorder, it is important to contact a doctor immediately.

Replenishing Electrolytes

Many consumers tend to think that replenishing electrolytes and water in the body means drinking a sports drink. But, one of the best ways to help regain your electrolyte balance is by eating real food.

Foods That Can Help Replace Electrolytes:

• Sodium - vegetable juice, soup, or canned vegetables can all supply sodium

  • Keep in mind, many people have a substantial sodium intake through their daily diets

• Chloride - seaweed, celery, and tomatoes

  • Much like sodium, the average American diet is typically not lacking in chloride

• Potassium - bananas, oranges, coconut water, and spinach

• Calcium - milk, yogurt, spinach, and other leafy greens

• Magnesium - pumpkin seeds, cashews, and avocados

Sports drinks can provide some value for clients sweating more than normal and need to rehydrate with energy (sugar), water, and electrolytes during a workout. It may help them get what they need without having to digest food so they can continue their physical activity. But, plenty of water and a well-balanced diet will usually help restore the electrolyte imbalance.

For additional information on post-workout nutrition check out this ISSA blog article.

Conclusion

Electrolytes play essential roles in many important body functions. It is important to keep them balanced to feel and perform your best. Clients can lose a lot of electrolytes during a workout that has them sweating excessively, so it's important to bring those electrolytes back into balance within the body for best health. Eating a healthy balanced diet with plenty of water should help replenish what the body needs.

Are you passionate about nutrition and interested in learning more? Check out ISSA's online Nutrition Course.

References

• Sweny, HL., Hammers, DW., "Muscle Contraction." ncbi.nim.nih.gov. Cold Spring Harb Perspect Biol. February 2018. https://www.ncbi.nlm.nih.gov/pubmed/29419405

• 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. Available from: https://www.ncbi.nlm.nih.gov/books/NBK21668/

• Beatriz, Lara. "Interindividual variability in sweat electrolyte concentration in marathoners." ncbi.nim.nih.gov. Journal of the International Society of Sports Nutrition. 2016. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4966593/