Is it better to drink water or electrolytes during a run?

October 3, 2025 •

4 min read

Even mild dehydration can reduce endurance performance by up to 10%. The debate of whether is it better to drink water or electrolytes during a run? is central to optimal athletic performance, with the right choice depending on a runner's specific needs and conditions.

Quick Summary

The best hydration strategy for running depends on duration, intensity, and conditions. Water is often enough for short sessions, while electrolytes become crucial for longer, more intense efforts to replace lost minerals and prevent imbalance.

Key Points

For Short Runs: For workouts lasting less than 60 minutes, plain water is typically sufficient to replace fluid lost through sweat.
For Long or Intense Runs: Electrolyte drinks are recommended for runs over 60 minutes or in hot, humid weather to replace lost minerals and prevent cramps and fatigue.
Sodium is Key: Sodium is the most crucial electrolyte for runners, helping the body to absorb and retain water, which is vital for maintaining fluid balance.
Risks of Hyponatremia: Drinking too much plain water during long events can dilute blood sodium levels, leading to a dangerous condition called hyponatremia.
Listen to Your Body: Pay attention to thirst and symptoms like muscle cramps or fatigue, which can indicate an electrolyte imbalance. Adjust your hydration strategy based on your body's signals.
Test During Training: Never try a new hydration plan on race day. Experiment with different fluid and electrolyte strategies during your long training runs.
Balance is Best: The optimal strategy often involves a balanced approach, incorporating both plain water and electrolyte supplements, depending on the run's demands.

The Foundations of Running Hydration

Proper hydration is a cornerstone of athletic performance, yet the ideal fluid choice during a run is not a one-size-fits-all solution. It depends on the length and intensity of the activity, as well as external factors like weather. For short, low-intensity runs, plain water is the gold standard, effectively rehydrating the body without unnecessary sugars or additives. However, as workouts get longer and sweat losses increase, the body loses more than just fluid; it also expels essential electrolytes, primarily sodium. In these scenarios, relying solely on water can be insufficient and, in some extreme cases, potentially dangerous.

The Role of Water

Water is the body's primary fluid source, essential for nearly all bodily functions, including regulating body temperature, lubricating joints, and transporting nutrients. During short, less intense runs (under 60 minutes), the body's internal electrolyte balance is typically stable enough that plain water is all that is needed to replenish lost fluids. The goal for these shorter efforts is simply to replace the volume of fluid lost through perspiration.

The Role of Electrolytes

Electrolytes are minerals, including sodium, potassium, and magnesium, that carry an electric charge and are vital for numerous physiological processes. In the context of running, they play a key role in:

Maintaining Fluid Balance: Sodium is especially critical for helping the body absorb and retain water, ensuring proper hydration at a cellular level.
Muscle Function: Electrolytes aid in nerve signaling and muscle contraction. Low levels can lead to muscle cramps, twitching, and weakness.
Nerve Function: Proper nerve transmission relies on a balanced electrolyte profile, which supports cognitive function and coordination.
Energy Production: Some electrolytes, like magnesium, are involved in the process of converting carbohydrates into energy.

When to Use Electrolytes

The decision to incorporate electrolytes into your running routine is based on a few key indicators. For runs lasting longer than one hour, particularly in hot or humid conditions, electrolyte supplementation is recommended. You should also consider electrolytes if you are a "salty sweater," which can be identified by visible white salt marks on your clothes or skin after a run. A high sweat rate, multi-session training days, or running at altitude are other factors that increase the need for electrolytes.

Water vs. Electrolytes Comparison

To help guide your choice, here is a comparison of when to prioritize water and when to opt for electrolytes based on common running scenarios:


Factor	Plain Water	Electrolytes
Run Duration	Short runs (< 60 minutes)	Long runs (> 60 minutes)
Intensity	Low to moderate intensity	High intensity or strenuous efforts
Weather	Mild or cool conditions	Hot, humid, or high-altitude conditions
Sweat Loss	Minimal sweat loss	Heavy or salty sweat loss
Symptoms	No specific symptoms; routine hydration	Cramps, fatigue, dizziness, or confusion
Pre-run	Adequate for most pre-run hydration	Beneficial for pre-loading before long or hot efforts
Post-run	Effective after short, easy runs	Recommended after long or intense efforts to speed recovery

Understanding the Risks: Hyponatremia

While the dangers of dehydration are well-known, overhydrating with plain water can also pose a serious risk, a condition known as hyponatremia. This occurs when blood sodium levels drop dangerously low, causing the body's cells, particularly in the brain, to swell with water. Symptoms include nausea, vomiting, headaches, and confusion, and they can be life-threatening if left untreated. Slower-paced runners and those who consume large amounts of plain water during long events are at a higher risk. Electrolytes, particularly sodium, help maintain the correct balance to prevent this dangerous dilution.

Practical Hydration Strategy for Runners

Developing a sensible hydration plan is key to maximizing your performance and safety. Here are some actionable tips:

Hydrate Pre-Run: Drink 17–20 ounces of water 2-3 hours before a run and a final 6-8 ounces about 15 minutes before starting.
Hydrate During the Run: For shorter runs, sip plain water. For longer efforts, aim for an electrolyte drink, consuming 6-8 ounces every 20 minutes. Listen to your body and drink according to thirst.
Test Your Sweat Rate: To determine your individual fluid and electrolyte needs, weigh yourself before and after a run. A one-pound weight loss equals approximately 16–24 ounces of fluid loss. This can help you tailor your strategy.
Experiment in Training: Never try a new hydration strategy on race day. Use your long training runs as a dress rehearsal to test different products and timings.
Replenish Post-Run: After long or hot runs, replenish fluids with both water and electrolytes to aid muscle repair and restore balance. You can choose from sports drinks, electrolyte tablets, or even a homemade solution.
Consume Whole Foods: A balanced daily diet provides many of the electrolytes you need. Foods like bananas (potassium), leafy greens (magnesium), and salted snacks (sodium) contribute to your mineral stores.

For more in-depth information on the specific physiological role of sodium and other electrolytes for athletes, consider consulting expert resources like those found on the Precision Hydration website.

Conclusion

Ultimately, the choice between water and electrolytes depends on the specific demands of your run. For short, low-intensity sessions, plain water is the clear winner. However, for any run lasting over an hour, or for intense workouts in warm conditions, electrolytes become an essential tool for maintaining performance, preventing muscle cramps, and avoiding dangerous conditions like hyponatremia. The best approach is to listen to your body, experiment with different strategies during training, and build a personalized hydration plan that accounts for your sweat rate, environment, and effort level. A balanced approach that incorporates both plain water and strategic electrolyte supplementation will help you perform your best and recover effectively.

Frequently Asked Questions

You may be a 'salty sweater' if you notice visible white streaks or a gritty feeling on your skin and running clothes after your sweat has dried. Your sweat might also sting your eyes.

Yes, a healthy and balanced diet provides many electrolytes. Natural sources include bananas, oranges, potatoes, leafy greens, and dairy products. These contribute to your baseline levels.

Yes, taking too many electrolytes can lead to an imbalance, with symptoms that can sometimes mirror those of low levels, such as nausea, cramps, and dizziness. Follow the manufacturer's recommended dosage for supplements.

Early symptoms of hyponatremia often include nausea, vomiting, headaches, and a sense of confusion. It can be easily mistaken for dehydration, but the treatment is opposite.

For runs over 60 minutes, a general guideline is to consume 6-8 ounces of fluid every 20 minutes. However, it is important to listen to your body and adjust based on thirst, sweat rate, and conditions.

For longer runs or hot weather, it can be beneficial to pre-load with electrolytes 30-60 minutes beforehand. Replenish during the run with a sports drink, and take electrolytes post-run to aid recovery.

Yes, a simple homemade solution can be made by mixing water with a pinch of salt, a splash of fruit juice for potassium and carbohydrates, and a bit of honey for energy.