Nutrition
Hydration for athletes: pre, intra, and post workout
For athletes, good hydration is not just liters: it is timing, electrolytes, and measuring whether you are hitting the target.
In general practice the 30-40 ml/kg/day rule works. For athletes, you need to add real sweat loss during the session and replenish thoughtfully before, during, and after.
Pre-workout
- 5-7 ml/kg in the 2-4 hours before.
- If urine is still dark 1 hour out, add an extra 3-5 ml/kg.
- Sodium: 30-50 mg/kg if the session is long (>90 min) or the climate is hot.
During the session
For sessions under 60 minutes, water is usually enough. Beyond 60-90 minutes, add carbohydrates (30-60 g/h) and sodium (300-700 mg/L). For efforts in heat, raise electrolytes before adding carbs.
Post-workout
Replenish 125-150% of the weight lost to sweat over the next 4 hours (measured by pre/post session weight, minus fluids consumed). Include sodium to retain the fluid.
Frequently asked questions
Always sports drinks?
No. For short, easy sessions they are unnecessary. Justify them from 60 minutes onward, significant heat, or multiple daily sessions.
About the author
Equipo Almendra
Editorial · Almendra
The Almendra editorial team brings together nutritionists, engineers, and product managers writing about how to run a modern nutrition practice.
Next step
Take clinical nutrition to the next level with Almendra
Design plans, manage clients, and automate follow-ups in a single platform.