Marathon Fueling Calculator
Plans race nutrition from your expected finish time and effort level: carbohydrate target per hour, total grams, number of gels and the interval between them, plus a fluid guideline. Based on the standard sports nutrition ranges of 30 – 60 g/h for efforts over an hour and up to 90 g/h for long races with a trained gut.
Read the full guide to this tool
Results
Notes
- Practice the exact plan in training: gut tolerance is trainable and race day is the wrong time to experiment.
- Above 60 g/h use mixed glucose+fructose sources; a single sugar saturates absorption around 60 g/h.
- Educational estimate for sport and training purposes, not professional coaching or medical advice.
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