The old way of eating for cycling was broken
For years the standard advice was: pick a calorie target, hit your macros, repeat daily. Same breakfast, same lunch, same dinner — Monday through Sunday regardless of what the training plan said.
That approach ignores something obvious. A rest day and a four-hour threshold ride are not the same physiological event. They don't demand the same fuel. Eating identically for both means you're either underfuelling hard days or overfuelling easy ones. Usually both.
Prof Sam Impey and the team at Liverpool John Moores University formalised what good coaches had been doing intuitively for years: match your carbohydrate intake to the work that's coming. They called it Fuel for the Work Required — FFTWR — and it changed how I coach nutrition at every level.
The core principle
Protein stays relatively stable day to day. Fat stays roughly stable. Carbohydrate moves.
That's the entire system. On days when training demands glycogen, carbs go up. On days when there's no training or only light recovery work, carbs come down. You're not restricting food — you're placing it where the body can actually use it.
Dr David Dunne, who's worked with elite endurance athletes on this exact framework, puts it simply: fuel the session, not the day. If tomorrow's session is 3x20 minutes at threshold, tonight and tomorrow morning need to reflect that. If tomorrow is a rest day, your body doesn't need 600g of carbs sitting in the tank with nowhere to go.
What a week actually looks like
Here's a practical example for a 75kg cyclist doing a typical three-build-one-recovery mesocycle.
Rest day (Monday): 2-3g carbs per kilogram. That's 150-225g across the day. Meals lean towards protein, vegetables, healthy fats. Think eggs and avocado for breakfast, a big salad with chicken at lunch, salmon with roasted vegetables at dinner. You're still eating well — just pulling the carb lever down.
Moderate training day (Tuesday, 90-minute endurance ride): 5-6g/kg. Around 375-450g of carbs. Porridge with banana before the ride, a normal lunch with rice or pasta, an evening meal with a decent portion of starchy carbs. The body gets what the session asks for.
Hard training day (Thursday, intervals): 7-8g/kg. 525-600g of carbs. This is where you actively front-load. Bigger portions of rice, pasta, bread. Extra fruit. Possibly a sports drink during the session. You're topping up glycogen stores before and replenishing them after.
Competition day or big sportive: 8-12g/kg. 600-900g of carbs. Race-day fuelling is its own protocol — the carb loading guide covers that in detail — but the principle is the same. The biggest demand gets the biggest fuel.
Recovery week: Carbs trend lower across the board because training volume drops 40-50%. You're not dieting — you're matching reduced demand. Most riders find their appetite naturally decreases in recovery weeks anyway.
The Big Blocks concept
Prof Impey talks about "Big Blocks" — clusters of consecutive hard training days where carbohydrate availability needs to be deliberately high. Think of a three-day block where you have intervals on Wednesday, a tempo ride Thursday, and a long ride Saturday.
Those three sessions are drawing down the same glycogen stores in sequence. If you eat like it's a rest day on the evenings between them, you start each session partially depleted. Not in a useful "train low" way — in a "can't hit the numbers and everything feels terrible" way.
Big Blocks get big fuel. The days around them get appropriately less. This is where periodised nutrition stops being theoretical and starts being a weekly rhythm you can feel working.
Common mistakes I see every week
Eating the same thing every day. The number one issue. Riders dial in a meal plan and never adjust it. Their Tuesday rest day looks identical to their Saturday five-hour ride day. The hard sessions suffer and the rest days accumulate unnecessary surplus.
Cutting carbs on hard days to lose weight. This is the fastest route to a terrible training block. Low carb availability on high-demand days means you can't hit target power, recovery between intervals is poor, and RPE is through the roof. You're not training harder — you're training worse.
Ignoring the meal before the session. FFTWR isn't just about the day — it's about the 12-18 hours before the key session. If Thursday has VO2max intervals, Wednesday evening's dinner matters. A low-carb dinner the night before a big session is self-sabotage dressed up as discipline.
Over-complicating it. You don't need to weigh every gram. The framework is simple: rest days lower, training days higher, big days highest. Once you've done it for two or three weeks, you'll know roughly what 5g/kg looks like on your plate without a food scale.
Where "train low" fits in
You'll hear about training with low glycogen availability as a performance strategy. There's good research behind it — Dr Dunne has written about the signalling benefits of occasional low-carb training sessions, particularly for fat oxidation and mitochondrial adaptation.
But "train low" is a precision tool, not a lifestyle. It means doing specific easy sessions on deliberately low glycogen to trigger a particular adaptation. It does not mean chronically underfuelling and calling it a strategy.
Within FFTWR, a "train low" session might mean doing a morning Zone 2 ride fasted, having skipped the evening carbs the night before. That's targeted. What it never means is doing your Thursday interval session glycogen-depleted. Key sessions get key fuel. Always.
How to start this week
Pick three days this week and tag each one: rest, moderate, or hard. Write down roughly what you'll eat on each. The only thing that changes meaningfully is the carb portion at each meal.
Rest day: smaller portion of rice/pasta/bread, more protein and veg on the plate.
Hard training day: bigger portion of starchy carbs at every meal, extra fruit, sports drink during the session.
That's it for week one. No calorie counting. No macros app. Just consciously putting more carbs on the plate when the training is bigger and less when it isn't.
After two weeks, most riders report that their hard sessions feel noticeably better. That's not placebo — it's having glycogen available when the muscles actually need it.
What to do next
If you're not sure whether nutrition is the thing holding you back — or whether it's training structure, recovery, or something else — the Plateau Diagnostic walks you through the four-question audit that identifies your actual limiter. Takes four minutes, costs nothing, and tells you exactly where to focus.