Fueling Plan

Carbs, fluid & sodium targets for any effort — with the science shown

Duration

Sport

Effort

Body weight

Temperature

°F

Carbs

55g/h

138 g total

Fluid

800ml/h

2.0 L total

Sodium

600mg/h

1500 mg total

Potassium

130mg/h

325 mg total

1754kcal

Energy

267g

Carb burn

2.7L

Sweat loss

59%

Glycogen

Fueling schedule

Time	Carbs	Fluid	Sodium	Potassium
Pre-start	25 g	150 ml	—	—
0:27	25 g	360 ml	270 mg	60 mg
0:55	25 g	360 ml	270 mg	60 mg
1:22	25 g	360 ml	270 mg	60 mg
1:49	25 g	360 ml	270 mg	60 mg
2:16	25 g	360 ml	270 mg	60 mg

Science-informed estimates, not medical or nutrition advice. Sweat rate and sweat sodium vary 2–3× between people — treat these as a starting point and calibrate with a weigh-in.

Show the basis & sources

Carbs: 30–60 g/h up to 2 h, 60–90 g/h beyond, up to 90–120 g/h when gut-trained (1:0.8 glucose:fructose).

Fluid: sweat rate ≈ base (sex) × intensity × heat; replace toward keeping loss under ~2% body mass.

Sodium: loss = sweat volume × sweat sodium (~920 mg/L default, 460–1,150 range); replace 300–700 mg/h on long or hot efforts.

Potassium: sweat K is ~4–8 mmol/L (~200 mg/L), so sodium is lost roughly 4–5× faster — K supports sodium, it never replaces it. Worth replacing past ~90 min.

Energy: cycling from power, running from distance, otherwise heart rate (Keytel) — carb share rises with intensity.

Sources