When should gels be taken in a marathon?

Most marathoners benefit from starting fueling at 45-60 minutes (before feeling depleted) and continuing every 20-30 minutes thereafter. Starting early is critical—once glycogen is depleted, performance cannot fully recover.

How many gels are needed for a 4-hour marathon?

Targeting 45-60 g carbohydrate/hour for a 4-hour event requires approximately 6-8 gels (each ~25-30 g carbs), or equivalent from sports drinks at aid stations. Exact needs depend on body size and pace.

Can you train the gut to absorb more carbohydrate?

Yes. Research shows regular intra-exercise carbohydrate consumption increases intestinal transporter expression, improving absorption capacity from ~60 g/hour to 80-90 g/hour over several weeks.

Marathon Fueling Interval Calculator

Calculate optimal gel/sports drink intake intervals for a marathon based on target race pace, body weight, and sweat rate to prevent glycogen depletion and maintain optimal hydration.

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Frequently Asked Questions

When should gels be taken in a marathon?

How many gels are needed for a 4-hour marathon?

Can you train the gut to absorb more carbohydrate?