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FREE SPORTS SCIENCE TOOL · ACSM · ISSN 2017 · HEARRIS 2025 META-ANALYSIS · INDIA-CALIBRATED

Carb Loading
Calculator.

Evidence-based glycogen supercompensation planner for marathon runners, cyclists, and triathletes. 10–12 g/kg/day protocols with personalised Indian meal plans for 1–3 day loading windows.

ACSM/AND/DC Position Stand
ISSN 2017 · 10–12 g/kg/day
Hearris 2025 Meta-Analysis
Indian Meal Plans · NIN IFCT-2017

Enter Your Event Details

Glycogen supercompensation planner · 10–12 g/kg · Indian meal plans

Carb loading is only beneficial for events >90 minutes. For shorter events, we'll calculate a glycogen "topping-up" plan instead. Always trial your loading protocol in training before race day.
Sex & Body Mass * All carb targets are expressed per kg body mass. Female athletes may require additional total energy intake — not just higher carb g/kg — to achieve glycogen supercompensation (ISSN 2017).
Sex
Event Type * Determines whether full carb loading (≥90 min) or glycogen topping-up (<90 min) protocol is indicated. Ultra-endurance events default to 3-day loading at 8–10 g/kg.
Loading Duration * Evidence supports 36–48h (2 days) as the optimal default for most marathon runners. 1-day is effective for highly trained athletes with full rest. 3-day allows lower daily targets spread over more time.
Training Taper Level * Taper enhances glycogen supercompensation. Full rest + high carb is the most effective combination. Continuing normal training reduces the net glycogen storage benefit.
Gastrointestinal Tolerance * High-carbohydrate loading can cause bloating, urgency, or cramping if fibre is not managed. GI-sensitive athletes need a lower-fibre, lower-fat meal plan (white rice, idli, dosa, banana over salads and pulses).
Dietary Pattern * Determines which Indian staples appear in your meal plan. Carb targets are identical — only the food sources change.
Performance Goal * Performance-focused athletes should use the upper end of the carb range (12 g/kg). Completion/finish athletes can use the lower end (10 g/kg) with less GI risk.

ACSM · ISSN 2017 · Hearris et al. 2025 · Burke et al. · Thomas et al. 2016 · NIN IFCT-2017

CARB TARGET (ACSM / ISSN 2017)
Complete the form →
g/kg/day
—
Target range
CARB KCAL
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kcal from carbs
Complete Your Race Nutrition Toolkit
VO₂max + Calorie Calculator Cooper test · ACSM fitness norms · Post-workout macros
Sports Hydration Calculator Sweat rate · ml/hr fluid target · Sodium replacement

WHAT YOU GET

Daily Carb Target (g)10–12 g/kg/day · ACSM/ISSN calibrated
Indian Meal PlansNIN IFCT-2017 · South/North/Mixed/Fruit
Day-by-Day Schedule1, 2, or 3-day loading protocols
Race Week TimelinePre-event meal + in-race fuelling tips
Weight Gain Context1–2 kg glycogen/water weight = beneficial
RED-S / GI GuardrailsEnergy availability + GI tolerance flags

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Our sports dietitian builds a complete race nutrition strategy — carb loading, pre-race breakfast, in-race fuelling, and recovery plan — completely free.

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EVIDENCE BASE

ACSM/AND/DC (2016)Joint Position Stand · Med Sci Sports Exerc
ISSN (2017)Nutrient Timing Position Stand
Hearris et al. (2025)Meta-analysis · Glycogen supercompensation
Thomas et al. (2016)J Acad Nutr Diet · Carb loading consensus
NIN IFCT-2017Indian food composition database

COMPLETE YOUR KIT

VO₂max CalculatorFitness classification · calories · post-workout macros
Hydration CalculatorSweat rate · ml/hr target · sodium guide
MetS + CKM CalculatorIDF MetS · AHA/ACC 2026 lipid targets

⚕️ This calculator provides evidence-based carb loading estimates for healthy endurance athletes. Always trial your loading protocol on a long training run or ride before race day. Athletes with diabetes, gastrointestinal disorders, kidney disease, or history of eating disorders should consult a sports dietitian before implementing a high-carbohydrate loading plan. The 1–2 kg weight gain from glycogen and water during loading is expected, normal, and beneficial for performance — it is not fat gain.