Race Day Nutrition
Endurance race fueling plan: carb loading, during-race intake, hydration, and sodium strategy by distance.
Inputs
Fill in the inputs and press Calculate to see your science-backed results.
How to use Race Day Nutrition
Endurance race fueling plan: carb loading, during-race intake, hydration, and sodium strategy by distance.
Choose measurements that describe your actual session or situation, confirm the units, then calculate. Read the result alongside its assumptions and use the tool again when your inputs change.
Inputs explained
Race distance
Choose the option that matches your context; available options include 10k, Half Marathon, Marathon.
Expected finish time (hr)
Enter a measured or estimated value (minimum 0.5) (maximum 24), using the unit indicated in the field label.
Bodyweight (kg)
Enter a measured or estimated value (minimum 40) (maximum 120), using the unit indicated in the field label.
Sweat rate (L/hr)
Enter a measured or estimated value (minimum 0.3) (maximum 2.5), using the unit indicated in the field label.
Expected conditions
Choose the option that matches your context; available options include Cold, Mild, Warm.
How to interpret the output
Treat calculated nutrition values as starting estimates. Appetite, training demands, dietary restrictions and individual needs vary.
Repeat measurements using similar conditions when monitoring trends. Numerical predictions can vary with input accuracy, measurement method and individual circumstances.
Limitations and responsible use
Never try new nutrition on race day. Test all fueling strategies in training. Individual gut tolerance varies widely.
Read the full disclaimerFrequently asked questions
What does the Race Day Nutrition estimate?
Endurance race fueling plan: carb loading, during-race intake, hydration, and sodium strategy by distance.
Which information do I need for this nutrition tool?
Provide Race distance, Expected finish time (hr), Bodyweight (kg), Sweat rate (L/hr), Expected conditions. Use your own relevant measurements and the units indicated in each field.
How should I interpret the result?
Treat calculated nutrition values as starting estimates. Appetite, training demands, dietary restrictions and individual needs vary. Compare results with your goals and other relevant observations rather than using a single output to make a major decision.
Disclaimer: Never try new nutrition on race day. Test all fueling strategies in training. Individual gut tolerance varies widely. Read the medical disclaimer.
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