David Dunne is the performance nutritionist whose work has shaped most of how Roadman talks about fuelling. He holds a PhD from Liverpool John Moores University in behaviour change, design thinking, and technology innovation in sports nutrition — which is a long way of saying he studies why athletes do or don't actually follow nutrition advice, not just what the advice should be. He came through the IOC sports nutrition diploma, has worked across World Tour cycling, Premier League football, the NBA, the Super League, and Ryder Cup Team Europe, and is now CEO of Hexis, the personalised sports-nutrition platform.
The Hexis principle, and the one Anthony comes back to most often, is carbohydrate periodisation. Most amateur cyclists treat their daily intake as a flat number. The better approach, and the one elite teams now use, is to match the carbohydrate intake to the training demand — high-carb on a threshold day, lower-carb on a rest day, deliberately moderate on a long aerobic day. The wins are obvious once you see them: better adaptation on the hard sessions, no excess on the easy days, and a much cleaner body composition arc over a season than any calorie-counting app will ever produce.
David's work is also why the Roadman in-ride nutrition guidance lands where it does. The 90 g/hour target most serious sportive riders aim at is real, but it has to be trained for — gut tolerance is an adaptation, not a starting condition. And the behavioural piece — the rehearsal of fuelling under race conditions, the pre-event meal practiced on long rides, the gel that has to actually agree with you on hour four — that's where most amateur fuelling plans collapse. The science of what to eat has been mostly settled for years. What David has done is the harder work of understanding why it doesn't get done.
If you've read any of the Roadman fuelling guides linked below, you've read his fingerprints.