Race Nutrition Planner
Bonking is optional. Use science to calculate your hourly carb and fluid intake requirements for your next event.
Your body has limited glycogen stores (usually ~1600-2000 calories). Once these deplete, you "bonk" or "hit the wall." To prevent this, you must replenish carbohydrates during the ride. The goal isn't to replace every calorie you burn, but to replace enough to keep your blood glucose stable and spare your muscle glycogen.
For short rides (1-2 hours). Easily achieved with 1 banana or a single energy gel.
The "Standard". The limit for glucose absorption alone. Requires focus to maintain for 3+ hours.
Pro Level. Requires "multiple transportable carbs" (Glucose + Fructose) ratio of 2:1. Gut training essential.
Just like your legs, your stomach can be trained. If you try to consume 90g of carbs per hour on race day without practicing, you will likely experience GI distress (bloating, nausea).
Start with 40-50g/hr in training and gradually increase it over weeks to teach your gut to absorb more fuel.
Per hour baseline. Individual sweat rates vary wildly (from 0.5L to 2.5L per hour). Dehydration increases heart rate (cardiac drift) and perceived exertion.
Per liter for long or hot events. Most cramping is caused by fatigue, but sodium depletion exacerbates it.
Once you bonk, it's too late. Your glycogen stores are depleted and no amount of mid-ride fueling will fully recover your performance. Prevention is everything—start fueling early and maintain consistent intake.