Whether you are heading out for a long run, climbing into the hills or spending a full day tramping, hydration can have a big impact on how you feel and perform.
Water does most of the heavy lifting, but during longer, hotter or more demanding adventures, electrolytes can become part of the equation too.
So what exactly are electrolytes, when do you need them and how do they fit into a good hydration strategy?
What are electrolytes?
Electrolytes are minerals that carry an electrical charge when dissolved in fluid. They include sodium, potassium, calcium, magnesium and chloride.
They help support important functions throughout the body, including fluid balance, nerve signaling and normal muscle function.
You naturally get electrolytes through food and drink, and for many everyday activities a normal diet and regular water intake will be enough.
What happens to electrolytes when you sweat?
When you run, tramp or exercise, your body produces sweat to help regulate temperature.
Sweat contains both water and electrolytes, particularly sodium. How much you lose varies considerably between people and can also change depending on the temperature, humidity, exercise intensity and duration.
For a short run or easy day walk, water and your normal meals may be all you need.
During long endurance sessions, demanding tramps or exercise in hot conditions, however, replacing some of the electrolytes lost through sweat can become more useful.
When do you need electrolytes?
There is no single rule that applies to every runner or tramper. Electrolytes may be worth considering when:
- you are exercising for an extended period
- conditions are hot or humid
- you are sweating heavily
- you are completing a long endurance event
- you have limited opportunities to eat during your activity
- you need to replace significant fluid losses afterwards
The Australian Institute of Sport notes that normal food intake is often sufficient to replace electrolytes lost during exercise, while electrolyte products can be useful when targeted fluid and electrolyte replacement is needed. In other words, you do not necessarily need an electrolyte drink every time you lace up your shoes.
Electrolytes and endurance
Long-duration exercise increases both fluid and electrolyte losses.
Sodium is particularly important because it helps regulate fluid balance. During prolonged activity, consuming fluids that contain sodium can also help support fluid retention and make it easier to replace what has been lost through sweat.
For runners, trampers and endurance athletes, the goal is not to consume as many electrolytes as possible. It is to match hydration to the demands of the day.
Your needs on a short winter trail run will be very different from a full-day tramp in warm conditions.
What about muscle cramps?
Electrolytes are often promoted as the answer to exercise-related cramp, but the reality is more complicated.
Cramping can be influenced by several factors, including fatigue, training load and individual susceptibility. Salt loss may contribute in some circumstances, but simply taking more electrolytes is not a guaranteed way to prevent cramp.
That is another reason to think about hydration as part of a broader approach that includes appropriate training, pacing, food, fluids and recovery.
Can you drink too much water?
Yes.
Drinking far more water than your body needs during prolonged exercise can dilute the sodium concentration in your blood. This is known as exercise-associated hyponatraemia.
It is relatively uncommon, but potentially serious.
The important lesson is that more water is not always better. Drink according to your needs rather than forcing large amounts of fluid simply because you are exercising.
Electrolytes and recovery
After a long run or tramp, replacing lost fluids is an important part of recovery.
If you have sweated heavily, consuming sodium through your normal meal or an electrolyte drink can help replace some of what has been lost.
Food is often an excellent recovery tool. A normal meal provides sodium and other nutrients alongside carbohydrates and protein, while an electrolyte product can be convenient when eating immediately is not practical.
Build hydration around the adventure
Good hydration does not need to be complicated.
Start your run or tramp well hydrated, carry enough fluid for the conditions and think about duration, temperature and how heavily you tend to sweat.
For shorter outings, water may be all you need. For longer days, endurance events or particularly hot conditions, electrolytes can become a useful part of your hydration plan.
The goal is not to follow a rigid formula. It is to understand what your body is losing and carry what you need to replace it.
Electrolyte FAQs
Do you need electrolytes when tramping?
Not necessarily. For shorter tramps in mild conditions, water and normal food may be enough. Electrolytes can become more useful during long days, hot weather or when you are sweating heavily.
When should runners take electrolytes?
Electrolytes may be useful during prolonged runs, endurance events or training in hot and humid conditions. Shorter runs generally do not require dedicated electrolyte products if you are eating and drinking normally.
What electrolytes do you lose through sweat?
Sweat contains several electrolytes, with sodium and chloride generally lost in the greatest amounts. Potassium, calcium and magnesium are also present in smaller quantities.
Do electrolytes prevent muscle cramps?
Not necessarily. Exercise-related cramps can have several causes, including muscular fatigue. Electrolyte loss may be one factor for some people, but electrolyte drinks cannot guarantee cramp prevention.
Can you drink too much water while exercising?
Yes. Consuming excessive amounts of water during prolonged exercise can reduce blood sodium levels and contribute to exercise-associated hyponatraemia. Hydration should match your individual needs and conditions.
Is water or an electrolyte drink better for exercise?
It depends on the activity. Water is suitable for many everyday runs and tramps. Electrolyte drinks can be useful during longer or hotter activities when fluid and sodium losses are greater.
