Marathon Hydration Plan

Marathon hydration plan basics. Pair gels with water, use aid stations strategically, and keep hydration simple to support carb intake.

Hydration and fueling work together. A simple plan: take carbs consistently and pair gels with water when possible.

Pair gels with water
Use aid stations intentionally
Keep it simple and repeatable

Fueling reference

Race-day carb targets and gel counts by finish time (baseline, no body weight entered)
Race	Finish time	Carbs/hour	Total carbs	Calories	Gels
Half marathon	1:20	45 g/hr	60 g	240 kcal	2
Half marathon	1:35	45 g/hr	71 g	284 kcal	3
Half marathon	1:50	45 g/hr	83 g	332 kcal	3
Half marathon	2:05	45 g/hr	94 g	376 kcal	4
Half marathon	2:20	45 g/hr	105 g	420 kcal	4
Marathon	2:50	75 g/hr	213 g	852 kcal	5
Marathon	3:15	75 g/hr	244 g	976 kcal	5
Marathon	3:45	75 g/hr	281 g	1124 kcal	6
Marathon	4:15	75 g/hr	319 g	1276 kcal	7
Marathon	4:45	75 g/hr	356 g	1424 kcal	7
Marathon	5:15	75 g/hr	394 g	1576 kcal	7

Method and sources

The numbers on this page are computed with the same code as the TrainPace calculators, from these published methods. They are training guidance, not medical advice.

Jeukendrup, A. (2014). A step towards personalized sports nutrition: carbohydrate intake during exercise. Sports Medicine 44(Suppl 1), S25–S33 — carbohydrate targets by event duration, and glucose + fructose for intakes above 60 g/hr.
Thomas, D.T., Erdman, K.A. & Burke, L.M. (2016). Nutrition and Athletic Performance (joint position statement of the ACSM, Academy of Nutrition and Dietetics, and Dietitians of Canada). Medicine & Science in Sports & Exercise 48(3), 543–568.

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