Whether you are heading out for a long run, hiking through the bush or spending a full day on the trail, 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 signalling 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, hike 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 hike, water and your normal meals may be all you need.
During long endurance sessions, demanding hikes or exercise in hot Australian conditions, 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 hiker. 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 required.
So you do not necessarily need an electrolyte drink every time you exercise.
Do you need electrolytes when exercising in the heat?
Hot conditions increase the challenge because you will generally sweat more as your body tries to regulate its temperature.
Long trail runs, hikes, rides and endurance events in Australian heat can therefore create much greater fluid losses than the same activity in cooler conditions.
That makes planning ahead particularly important.
Carry enough water, understand where you can refill and consider whether an electrolyte drink or supplement is appropriate for the duration and conditions.
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 containing sodium can help replace some of what you are losing through sweat.
The goal, however, is not to consume as many electrolytes as possible.
A short morning run and a six-hour summer hike place very different demands on your body. Your hydration strategy should reflect that.
What about muscle cramps?
Electrolytes are frequently marketed as a solution for exercise-related cramp, but cramping is more complex than simply running low on salt. Factors such as muscle fatigue, training load and individual susceptibility can all play a role.
Electrolyte loss may contribute in some situations, but taking an electrolyte supplement cannot guarantee that you will avoid cramp.
Can you drink too much water?
Yes.
Consuming 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 lesson is simple: hydration is about balance. More water is not automatically better.
Electrolytes and recovery
After a demanding run or hike, replacing lost fluids is an important part of recovery.
If you have sweated heavily, sodium from food or an electrolyte drink can help replace some of what you have lost.
A normal meal often does the job well because it supplies sodium alongside carbohydrates, protein and other nutrients. Electrolyte products can provide a convenient alternative when eating straight away is difficult.
Build hydration around the adventure
Good hydration is about matching what you carry to the conditions ahead.
Start well hydrated, take enough fluid for your route and consider the temperature, duration and intensity of the activity.
For shorter outings, water may be all you need. During long adventures, endurance events or hot-weather exercise, electrolytes can be a useful addition to your hydration strategy.
Knowing when you actually need them is far more valuable than simply adding electrolytes to every bottle.
Electrolyte FAQs
Do you need electrolytes when hiking?
Not always. Water and normal food are often sufficient for shorter hikes. Electrolytes can become more useful on long hikes, in hot conditions or when you are sweating heavily.
When should runners take electrolytes?
They may be useful during prolonged running, endurance events or training in hot and humid weather. Most shorter runs do not automatically require electrolyte products.
What electrolytes do you lose through sweat?
Sweat contains several electrolytes, particularly sodium and chloride. Potassium, calcium and magnesium are also lost in smaller amounts.
Do electrolytes prevent muscle cramps?
Not necessarily. Muscle cramps can have several causes, including fatigue. Electrolyte loss may contribute for some people, but electrolyte drinks cannot guarantee prevention.
Can drinking too much water be dangerous?
During prolonged exercise, consuming excessive amounts of water can dilute blood sodium and contribute to exercise-associated hyponatraemia. Aim to drink according to your needs rather than forcing excessive fluid intake.
Are electrolytes more important when exercising in hot weather?
They can be. Hot conditions often increase sweat and fluid losses, particularly during prolonged exercise. This can make fluid and electrolyte replacement more important than during shorter activities in cooler weather.
