How is the race-day fuelling plan calculated?

The plan is built from your next race on your calendar (its distance and climb) and your latest weight, not pulled from thin air. The pieces:

• Pre-race breakfast is sized to roughly 2 g of carbs per kg of body weight, in easy, low-fibre foods.
• On-course carbs per hour scale with how long you are likely to be out there: around 30 g per hour for efforts under about 90 minutes, 60 g per hour up to roughly three hours, and 80 g per hour for longer ultras, where mixing glucose and fructose lets your gut absorb more.
• Fluids are set at about 500 ml per hour with electrolytes, more on hot climbs.

The duration estimate comes from the race distance and elevation, so a hilly course is given more time (and therefore more total fuel) than a flat one of the same length. If a race has no distance set yet, you still get sound general guidance and a note about the gap.