Do you need electrolytes or is water enough?

Water is enough for most people most of the time. Electrolyte products earn their place in specific situations: long sessions, heat, heavy or salty sweating and limited food. Our evidence rating for sodium replacement in endurance events is moderate, and the Australian Institute of Sport places electrolyte supplements in Group A (sports foods).

When is water enough?

• Sessions under about 60–90 minutes at normal intensity.
• Training in cool or mild conditions.
• Gym workouts where you eat a meal afterwards.
• Children and teens in normal school sport: water and food are usually enough.

Your daily diet already supplies sodium, and most people eat well above their minimum needs.

When do electrolytes help?

Cramps are multifactorial; they are not always due to low sodium, so electrolytes are not a guaranteed fix. See do salt tablets prevent cramps.

What is the risk of too much water?

Exercise-associated hyponatraemia (blood sodium below 135 mmol/L) is mainly caused by drinking more than you sweat, particularly in events beyond four hours and for slower runners. Symptomatic cases are uncommon (about 1% in one study of 2 135 endurance athletes), but severe cases need emergency treatment. Sodium in a drink slows this down but cannot prevent it if you overdrink. The practical rule is to drink to thirst. A loss of about 3% of body mass is generally tolerable in cool-temperate conditions.

What do electrolytes cost in South Africa?

October 2026, per serving, from shelf price (our calculation):

• Biogen Electrolyte, 3 x 10 sachets: R139–R155 at Dis-Chem, about R5.17 each.
• Lifestyle Electrolyte Fizzy, 10 tablets: R48–R53 at Dis-Chem, about R5.30 each.
• REVIVE Raw, unflavoured, 30 sachets: R319–R399 at Faithful to Nature, about R13.30 each.

Sodium per serving is not published on the retailer pages for these products, so check the pack. See best electrolyte powder in South Africa and the electrolyte comparison. Cheaper still: see homemade electrolyte drink.

Who should be careful with sodium?

People with high blood pressure, heart disease or kidney disease, those on diuretics or other regular medication, and pregnant women, should check with their doctor before using high-sodium products. Cooling, shade and acclimatisation matter more than any sachet in dangerous heat.

How do you decide?

1. Under 90 minutes: water and a meal.
2. Over 90 minutes in heat: add sodium via a drink, food or sachet.
3. Do a sweat test to refine; see how much sodium per hour when running in South African heat.
4. Always practise in training.

When should you see a doctor?

Seek medical help for confusion, severe headache, vomiting or collapse during or after exercise. This is general information, not personal medical advice.

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