Hypotonic Drink

Definition

A drink with an osmolality lower than blood plasma (<250 mOsm/L), allowing rapid hydration with less sugar.

How it works

Hypotonic drinks have an osmolarity lower than blood, favouring water flow from the digestive tract to the blood for rapid hydration. They contain little to no sugars (0-4 g/100 ml), making them ideal for short efforts (<60 minutes), intermittent sports, or in very hot conditions where hydration takes priority over energy. Sodium (usually 10-20 mmol/L) improves water absorption without significant energy intake. They are also recommended during the day outside of sports activity for hydration without excess calories. Compared to isotonic solutions, they empty the stomach more quickly.

Role

Ensure rapid hydration with minimal energy intake, ideal for short efforts or in hot conditions.

Examples

• Plain water
• Water with a pinch of salt
• Low-sugar sports drink
• Diluted fruit juice
• Coconut water (naturally rich in minerals)

Recommendations

Use for efforts under 1 hour or as a quick post-effort rehydration drink. Drink 200-300 ml every 15-20 minutes according to your hydration needs. Combine with energy-rich foods if the effort lasts longer.

Key takeaway

Hypotonic drinks are optimal for rapid hydration in short efforts or daily rehydration.

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