Why and How to Replace Sodium During Long Rides/Runs

Sweating Sodium/Electrolyte Loss

Sweat is our body's primary way to regulate its temperature during physical activities. However, sweat is not just water; it's a mixture of electrolytes, with sodium being the most significant.

As we sweat, we lose these essential electrolytes, which need to be replenished to maintain optimal body function. Understanding this balance between hydration and electrolytes becomes even more critical as the duration of your activity increases. Not only does this impact your performance, but it also affects your overall ability to train at your highest level.

Sodium's Role

Sodium plays a crucial role in maintaining fluid balance and blood pressure. It is also essential for muscle function and nerve impulse transmission. When we exercise, our body relies on sodium to help keep our muscles working efficiently and our nerves firing correctly.

What Happens When We Lose Too Much Salt?

As your sweat loss increases, your blood volume gradually decreases because sweat is drawn from your blood plasma. This reduction in blood volume makes it harder for your body to pump blood to your skin and working muscles, leading to increased effort and fatigue. Additionally, significant sodium loss can result in muscle cramping and other symptoms of electrolyte imbalance.

While drinking pure water helps to offset the amount of sweat you're losing, it does not replace the sodium lost. Therefore, it is critical to replace your sodium loss to avoid your blood becoming too diluted, a condition known as hyponatremia. Hyponatremia can lead to serious health issues, including nausea, headache, confusion, and in severe cases, seizures or coma.

An endurance athlete out for a run on the boardwalk

Your Personal Sweat Rate

Every individual has a different sweat rate, which can vary depending on the temperature and intensity of the activity. Cooler temperatures and lower intensities typically result in less sweating, while hotter temperatures and higher intensities increase sweat rates.

The best way to identify your personal sweat rate is through a sweat test, which measures:

  • The total amount you sweat in a given time frame
  • The sodium concentration in your sweat

Knowing these factors can help you tailor your hydration and electrolyte replacement strategy to your specific needs.

Is There an Optimal Electrolyte Formula?

An optimal electrolyte formula can enhance performance and absorption while being gentle on the stomach. Here are some key components:

  • Sea Salt: Less processed and contains more minerals than regular salt. It is composed of 84% chloride and 16% trace minerals.
  • Sodium Citrate: Reduces the salty taste and acts as a mild buffer. It also lowers the osmolarity of the solution, making it easier to absorb.
A man on a bike ride, taking a drink from a water bottle

Sea Salt, Sodium Citrate, and Chloride: How they work together

  • Optimal Absorption: Sodium citrate is an alkaline form of sodium, which may be more palatable and easier on the stomach, improving absorption.
  • Enhanced Performance: This blend helps maintain electrolyte levels, supporting sustained performance and preventing muscle cramps.
  • Versatility: Easily incorporated into sports drinks, making it convenient for athletes to consume during activities.
  • Fluid Balance: Chloride works alongside sodium to help maintain proper fluid balance and blood volume.

How to Effectively Replenish Sodium Loss

Many studies have shown that, on average, athletes lose 1000 mg of sodium per liter (32 oz) of sweat, with some athletes exhibiting even higher losses in lab tests. Therefore, athletes need to replenish their sodium levels during training and racing to maintain optimal body function. The intensity of your training and how much you sweat will play a crucial role in determining how much sodium you need to intake.

  • For higher intensity training and high sweat rate sessions: Drink ~1,000-2,000 mg of sodium with 20-30 oz of water during training.
  • For lower intensity training and lower sweat rate sessions: Drink ~1,000 mg of sodium with 20-30 oz of water during training.
  • Rehydration after training: Drink ~1,000 mg of sodium with 20 oz of water.


If you are looking for a product with a perfect ratio of sodium, especially in the form of both sea salt and sodium citrate, consider trying RAW Nutrition’s electrolyte product, REPLENISH. This formula is a comprehensive solution for athletes looking to maintain peak performance over long distances. Replenish will allow you to replace your sodium needs while keeping your gut and taste buds happy.


The information being presented in this blog is intended to be used as educational or resource information only. It is not intended to be a substitute for medical advice from your healthcare provider. This content should not be used for the diagnosis or treatment of any medical condition. If you have any questions or concerns about your health, please contact your healthcare provider. You should call 911 for all medical emergencies. Raw Nutrition is not liable for any advice or information provided on this blog, which advice or information is provided on an “as-is” basis, and assumes no liability for diagnosis, treatment, decisions, or actions made in reliance upon any advice or information contained on this blog. No warranties, express or implied, are made on the information that is provided.

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June 24, 2024 — Aaron Napoles
Tags: sodium

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