Bank of America Chicago Marathon fuel plan: carbs, fluid and sodium per hour.

October 10, 2027, Chicago, United States. Set your finish time and the plan follows.

Distance
42.195 km
Climbing
Not published
Typical temperature
10 to 17 °C · 50 to 63 °F
Aid stations
20

Your numbers

Sport
h:mm, like 5:30
kg
Keeps fluid loss under 2%. Never shared.
ml/h
Don't know it? Work it out
mg/l
From a sweat sodium test. Leave it empty if you haven't done one.
Conditions
Gut training
How used your gut is to taking carbs while you train.

Your plan

Marathon · 4 h

Carbs an hour

75g

The research range for this race is 60 to 90 g; your gut training sets where you start. Above 60 g, use glucose and fructose, about 2:1.

Jeukendrup 2014Viribay 2020+4 more

Fluid an hour

To thirst

Without a sweat rate the research says drink to thirst. Do the sweat test to get a range.

NATA 2017ACSM 2007

Sodium an hour

300 to 1,000mg

Sweat sodium varies a lot between people. A sweat sodium test gives you your own number.

Baker 2017NATA 2017+1 more

About 300 g of carbs over the race. That is a 25 g gel every 20 minutes, or the same carbs from drink and chews.

Rehearse it in training first: the gut adapts in 2 to 4 weeks. Costa 2017

Hand it to your AI

Your AI can check these numbers against your training and adjust them. The prompt has your results filled in.

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I'm racing a Marathon and expect to finish in 4 h. I haven't measured my sweat rate. Conditions look mild, and my gut is in some training for fueling. A race fuel calculator built on the research (Jeukendrup 2014, the ACSM 2016 position stand) gave me: 75 g carbs an hour (glucose and fructose, about 2:1), about 300 g in total; fluid: drink to thirst, no sweat rate yet; 300 to 1,000 mg sodium an hour. Check this against my training and how my gut has handled fueling, then build my race day plan: what to take and when, with real products I can buy.

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Gemini, Grok Bot, Dots, Muse and Cue: copy the prompt and paste it in.

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With Memory.fit, your AI would already know your sweat rate.

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The course

What to know about Bank of America Chicago Marathon.

A flat and fast course that starts and finishes in Grant Park. Runners pass through 29 neighborhoods.

On course: Gatorade Endurance Formula (lemon-lime), Maurten Gel 100 (caffeinated and caffeine free), Chiquita bananas. Train with what the course hands out, or carry your own.

KmLegWhat's there
2.6runGatorade Endurance Formula, water
5.2runGatorade Endurance Formula, water
8.1runGatorade Endurance Formula, water
9.3runGatorade Endurance Formula, water
11.7runGatorade Endurance Formula, water
14.2runGatorade Endurance Formula, water
16.3runGatorade Endurance Formula, water
18.5runGatorade Endurance Formula, water
20.3runGatorade Endurance Formula, water, Maurten gels
21.9runGatorade Endurance Formula, water
23.5runGatorade Endurance Formula, water
25.3runGatorade Endurance Formula, water
27.2runGatorade Endurance Formula, water
29runGatorade Endurance Formula, water, Maurten gels
30.9runGatorade Endurance Formula, water
32.5runGatorade Endurance Formula, water, Chiquita bananas
35.9runGatorade Endurance Formula, water, Chiquita bananas
37.1runGatorade Endurance Formula, water, Chiquita bananas
39.4runGatorade Endurance Formula, water
40.6runGatorade Endurance Formula, water

Race details checked October 17, 2026 from chicagomarathon.com, chicagomarathon.com, chicagomarathon.com, cdn.chicagomarathon.com, weatherspark.com. Courses and aid stations change: check the official page in race week.

Train for it

Train for Bank of America Chicago Marathon with your AI.

With Memory.fit, your AI reads your real training, sleep and fuel, plans your weeks toward race day and shows the plan in the app.

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Questions

Bank of America Chicago Marathon: questions.

  • At a typical finish of 4 h, the research range is 60 to 90 g an hour, as glucose and fructose, set by how trained your gut is. Enter your own finish time above for your number.

  • Average daily low and high in Chicago in October (Weather Spark). run from about 10 to 17 °C (50 to 63 °F). Heat raises your sweat rate, so do a sweat test in similar weather.

  • The organizer lists 20 aid stations; the table on this page has each one by km. Check the athlete guide in race week, as positions can change.

Not medical advice. Memory.fit is not affiliated with Bank of America Chicago Marathon or its organizer.

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