When should I practice fueling?
During training sessions that resemble the race’s duration and intensity. Use the products you plan to race with and change one variable at a time.
How do I calculate what to carry?
Multiply expected hours by your practiced grams per hour. Divide by the grams in a gel only if gels are your sole carbohydrate source. Drinks and food count too.
What about water and sodium?
Carbohydrate totals do not prescribe hydration. Use repeated sweat-rate observations and the conditions to discuss a drinking plan. Sweat rate does not measure sweat sodium.
Should I try a higher intake on race day?
No. Race morning is a poor time to test an unfamiliar product or a new hourly intake. Bring the plan you have rehearsed.
Where does this guidance come from?
Primary source and methodology. Use the calculator’s method notes for assumptions. Coaching decisions still require your context.
Use the related calculator