Race Day Fuel Planner
Science-backed nutrition planning for your next race. Calculate carbs, hydration, and electrolytes based on duration, weather, and your experience level.
Trained guts can handle up to 90g/hr carbs vs 60g/hr for beginners.
Carbohydrates
60g/hr
210g total
Fluids
500-700ml/hr
2100ml (71oz) total
Sodium
500-700mg/hr
2100mg total
Practice Makes Perfect
Always practice your fueling strategy during training runs. Never try new nutrition on race day. Start with smaller amounts and gradually increase as your gut adapts.
Carbohydrate intake recommendations are based on current sports nutrition research, with rates adjusted for effort duration and intensity.
Gut training is crucial—the GI system can be trained to absorb more carbs with regular practice, increasing from ~60g/hr to up to 90g/hr.
Carb Rate Guidelines:
- • <60 min: Water sufficient, minimal fueling
- • 60-90 min: 30-45g/hr
- • 90-150 min: 45-60g/hr
- • >150 min: 60-90g/hr
Share this tool with your training group or embed it on your coaching website.
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How to use this fuel planner
- Race Day mode: Enter your expected race duration, conditions, and fuel preferences to get a personalized fueling timeline.
- Training Week mode: Enter days until your race and body weight to get carb loading targets.
- Practice your plan: Always test your nutrition strategy during long training runs before race day.
- Adjust based on feel: These are starting points—everyone responds differently to nutrition during exercise.