A 200km sportive is a step-change in fuelling demand from a 100km event, not a linear extension. Glycogen depletion across 6-9 hours of moderate-intensity work breaks the shortcuts that work at the shorter distance — under-eating early can be patched in a 100km ride; in a 200km ride it ends in a bonk somewhere in the closing 60km. The protocol below is the new amateur baseline for any event over 6 hours, not an upper bound for elite riders.
Pre-ride loading. Eat 2-3g of carbs per kg of bodyweight 2-3 hours before the start — for a 75kg rider, that's a 150-225g breakfast (porridge with banana and honey, toast, juice). 30-60 minutes pre-start, top up with 30-40g of fast carbs (gel, banana, small flapjack). The aim is to roll out with full glycogen and stable blood sugar so you're not chasing a deficit from minute 60.
In-ride: begin with a carbohydrate rate already tolerated in long training rides and progress only through deliberate gut training. A reminder can keep intake consistent, but the foods and concentration must suit the rider. Plan fluid separately from representative sweat-loss observations and event access. Sodium concentration varies widely, so do not infer a fixed sodium dose from fluid loss or body size.
Gut training is the non-negotiable. Most amateurs cannot tolerate 120g/hr on day one — it has to be trained, the same way you train threshold power. Build by 10-15g/hr per week from your current intake on weekly long rides, and never test a new fuelling number for the first time on race day. On the podcast, Dr David Dunne has been explicit that the 90-120g/hr World Tour standard is achievable for amateurs but only with deliberate gut training in the 8-12 weeks before the event. Use the Roadman fuelling calculator to model your specific weight, duration, and conditions.