Proper hydration is not just about drinking water—it’s about strategy, timing, and electrolyte balance. Science shows that a personalized hydration plan can significantly improve performance and recovery.

The Myths vs. Reality

Myth: Drink as much as possible. Reality: Overhydration (hyponatremia) is as dangerous as dehydration. It dilutes blood sodium levels and can be fatal.

Myth: Thirst is a bad indicator. Reality: For most recreational runners, drinking to thirst is effective. However, for long distances or competitive pacing, a structured plan is better.

Hydration Timeline

Pre-Run (The Setup)

  • Start Early: Hydrate consistently in the days leading up to your long run.
  • 2-4 Hours Before: Drink 500-600ml (17-20 oz) of fluids.
  • 15 Minutes Before: Sip 300ml (10 oz) of water or sports drink.

During the Run (The Maintenance)

  • Frequency: Aim for 100-200ml every 15-20 minutes.
  • Electrolytes: For runs over 60 minutes, plain water isn’t enough. You need sodium (300-600mg/hour) to retain fluid and prevent cramping.
  • Sweat Rate: Calculate your individual sweat rate by weighing yourself before and after a 1-hour run. Each pound lost = ~16oz of fluid needed.

Post-Run (The Recovery)

  • The Golden Window: Rehydrate within 30 minutes to 2 hours post-run.
  • The Formula: Drink 1.5x the amount of fluid lost. If you lost 1lb (16oz), drink 24oz.
  • Sodium + Carbs: Pair fluids with electrolytes and carbohydrates to accelerate absorption and replenish glycogen.

What to Drink?

ConditionRecommended DrinkWhy?
Runs < 60 minsWaterSufficient for hydration without extra calories.
Runs > 60 minsSports DrinkProvides carbs for fuel and electrolytes for balance.
High Heat/HumidityElectrolyte MixHigher sodium concentration needed to combat heavy sweating.
RecoveryChocolate MilkPerfect ratio of carbs to protein plus hydration.

Signs of Dehydration

  • Dark yellow urine
  • Headache or dizziness
  • Elevated heart rate (cardiac drift)
  • Early fatigue

Key Takeaway

Hydration is highly individual. Test different strategies during training, not on race day. Knowing your body’s specific needs is the ultimate competitive advantage.