Sodium
The main electrolyte lost in sweat
Sodium supports fluid balance and can improve drink palatability and retention. Needs vary with sweat rate, sweat sodium, heat, clothing and duration.
Hydration and electrolytes
Match your hydration to your efforts
Water, low-calorie electrolytes and carbohydrate drink mix solve different problems. Consider the heat, sweat, duration and carrying capacity, then choose a product you can mix and tolerate on the move.
The short answer
Plain water may be enough for short, cool sessions
Electrolytes become more useful when sweat losses are meaningful, particularly in heat, long sessions, indoor training or repeated work. Sodium is the main electrolyte lost in sweat, but individual losses vary and more sodium is not automatically better.
What electrolytes do
Replace a practical part of sweat loss
Water
Enough for many ordinary sessions
Shorter, cooler or easy sessions may need only normal meals and water as thirst suggests.
Testing
Use your own repeatable conditions
Compare body mass, thirst, urine, comfort and performance around similar sessions. Avoid forcing fluid beyond comfort.
Choose the format
Separate hydration from fuel when the job changes
Tablets
Simple bottle dosing
Convenient for low-calorie electrolyte drinks when carbohydrate comes from food, gels or chews.
Powders
Flexible concentration
Check the label and bottle volume. A scoop designed for 500 ml does not create the same drink in a one-litre bottle.
Carbohydrate mix
Fuel and fluid together
Useful in longer steady work, but changing concentration changes both jobs at once.
Ready to drink
Convenience with a fixed formula
Easy to use, but check the actual sodium, carbohydrate and serving size rather than the front label alone.
Where it helps
Match the product to the context
Endurance
Long sessions and races
Use duration, temperature, aid access and individual sweat response to decide fluid and sodium.
Hybrid
Hot rooms and repeated efforts
Indoor heat and limited airflow can raise sweat losses even when the session is not very long.
Everyday
Do not turn routine thirst into a supplement need
Normal food and water cover most daily hydration. Products can be useful for convenience or specific high-loss situations.
Compare the options
Water, electrolytes or carbohydrate drink mix?
| Option | Best fit | Carbohydrate | Main check | Avoid |
|---|---|---|---|---|
| Plain water | Short, cool or easy sessions | None | Drink to comfort and thirst | Forcing large volumes |
| Low-calorie electrolyte | Hot, sweaty or longer sessions when fuel is separate | Low or none | Sodium per serving and bottle size | Assuming higher is always better |
| Carbohydrate drink mix | Longer endurance work needing fuel and fluid | Meaningful | Concentration and total hourly fuel | Adding gels without counting the drink |
| Ready-to-drink product | Convenience and fixed dosing | Varies | Full label and serving size | Judging by marketing name alone |
On a phone, swipe the table sideways to compare every column.
Shop by format
Focused hydration ranges
Current prices, options and availability are shown with each product.
Common questions
Hydration and electrolyte questions
General guidance for healthy adults. Individual needs still vary.
Do I need electrolytes for every workout?
No. They are more useful when sessions are long, hot or very sweaty, or when turnaround is short.
Is more sodium better?
No. Sodium needs vary. Use the product label, bottle volume, conditions and your own tested response rather than chasing the highest number.
What is the difference between an electrolyte drink and a carbohydrate drink mix?
An electrolyte drink may contain little or no carbohydrate. A carbohydrate drink mix provides fuel as well as fluid, so both count towards the plan.
Can I combine drink mix with gels, chews or bars?
Yes, but count carbohydrate and caffeine across the bottle and every other source. Follow the mixing instructions and test the complete combination in training before relying on it during an event.
Is drink mix better if my stomach gets bad when running?
Not automatically. Some athletes find a liquid format practical, but concentration, amount, heat, effort, fluid and individual response all matter. Follow the label, practise the intended mix and change one variable at a time. Persistent, severe or unusual symptoms need appropriately qualified medical or dietetic advice.
Sources and further reading
Check the evidence
These links go to primary research, consensus statements or recognised sporting organisations. They are included where checking the source adds useful context.
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IOC consensus statement on sport events in the heat
British Journal of Sports Medicine, 2023
Current consensus on heat, hydration, individual sweat losses and sodium.
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Nutrition and Athletic Performance
Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM, 2016
Consensus guidance on matching carbohydrate, fluid and recovery nutrition to exercise demands.
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Exercise-associated hyponatraemia consensus statement
Clinical Journal of Sport Medicine, 2015
Explains why overdrinking hypotonic fluid can be dangerous during endurance events.
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The Effect of Gut-Training and Feeding-Challenge on Gastrointestinal Status
Sports Medicine, 2023
Systematic review of repeated carbohydrate or fluid exposure during training and gastrointestinal outcomes.
