Race Day Nutrition Calculator

Race distance and pace are multiplied to estimate elapsed race time, and that duration drives the fueling schedule. The carbohydrate rate is deliberately stepped rather than continuous: races under one hour receive 20 grams per hour, races from one hour to under two and a half hours receive 45, and longer events receive 75. Total carbohydrate multiplies the selected rate by race hours and rounds to whole grams. Because both distance and pace affect elapsed time, either can move an event across a rate boundary as well as change its total duration. Fluid per hour comes from sweat rate minus 200 milliliters per hour, with a minimum replacement basis of 200 milliliters, then converts to fluid ounces.

Sodium uses the entered sweat rate at 0.5 milligram per milliliter and multiplies that hourly amount by race time. The gel count is a timing proxy, not total carbohydrate divided by gel size: fueling begins after 45 minutes, and the engine counts completed 35-minute windows thereafter. Body weight is converted to kilograms for display but does not influence carbohydrate, fluid, gels, or sodium. The calculator does not model aid-station spacing, drink carbohydrate, weather, gut tolerance, pre-race meals, or sodium concentration measured from the athlete's sweat. Practice any plan during training rather than treating the generated quantities as a first-time race-day instruction.