1. Why Hydration Matters More in the Heat
- Performance & cooling: Even mild dehydration (1–3% body weight loss) decreases blood volume, raises heart rate, and impairs sweat-based cooling.
- Cognitive sharpness: Dehydration can reduce focus and reaction time—critical during hard workouts and races.
2. Pre‑Run Prep: Start Ahead of Time
- Load fluids early: Drink 16–20 oz (500–600 mL) 2–3 hours before, then another 8 oz about 30 minutes before running.
- Daily hydration matters: Pale yellow urine = good. Dark yellow = drink up.
3. During the Run: Maintain Balance
- Sip regularly: Aim for 5–10 oz (150–300 mL) every 20–30 minutes, more if it’s hot or humid.
- Replace electrolytes: Use a sports drink or sodium supplement on runs longer than 60 minutes.
- Customize it: Sweat rate and sodium loss vary. Consider sweat testing or using patches if you’re training seriously.
4. After the Run: Recovery
- Rehydrate smart: Drink 16–24 oz (500–700 mL) per pound of body weight lost during the run.
- Don’t forget salts: Keep sipping electrolyte drinks or eat salty snacks post-run.
5. Smart Daily Strategies
- Electrolytes on rest days? Only if you’re sweating a lot (heat, sauna, intense cross-training).
- Hydrating foods: Add watermelon, cucumbers, leafy greens, yogurt, and coconut water to your routine.
6. Heat Acclimation: Build Long‑Term Tolerance
- Benefits: Training in heat for 7–14 days increases plasma volume and improves sweat efficiency.
- How to acclimate: Short, easy runs in the heat. Increase exposure gradually and avoid hard efforts early on.
7. Watch for Hydration Red Flags
- Warning signs: Dark urine, cramps, dizziness, nausea, fatigue. Don’t ignore them.
- Don’t overdo it: Drinking too much plain water without electrolytes can lead to hyponatremia (low blood sodium).
Final Tips
- Hydrate smart, not just hard: Combine water with electrolytes and smart food choices.
- Track and tailor: Weigh yourself before and after runs to learn your fluid loss pattern.
- Train your heat response: Build heat tolerance gradually for safer summer running.
- Stay alert: Hydration needs change day to day. Listen to your body.