Eating for two goals at once

You want to be leaner and you want to be stronger. Both need protein; they disagree about calories. The resolution is timing, not compromise.

• Protein: 130–155 g a day, every day, all 19 weeks. That’s roughly 1.8–2.2 g per kilo. It is the one number that serves fat loss, strength and recovery simultaneously, and it’s the number most runners miss by a wide margin. Spread it across 3–4 feedings rather than loading it at dinner.
• Deficit now, through week 8 only. About 350 kcal below maintenance — enough for roughly 0.3–0.4 kg a week, which is 3–4 kg by the end of block 2. Slower than you’d like. Faster loss than that at rising running volume costs muscle and bone, and the bill arrives as a stress fracture in week 11.
• Maintenance from week 9 onwards. Not negotiable. Running 55–66 km a week in a calorie deficit is the textbook route to low energy availability: bone stress injuries, suppressed immunity, flat training, and adaptations that simply don’t happen. Whatever fat is left at week 9 stays until after the race. It’ll come off faster afterwards anyway.
• Carbohydrate is a training variable, not a moral one. Eat properly before Tuesday’s session and Saturday’s long run, and eat carbohydrate afterwards. The deficit comes out of the easy days, never out of the two runs that matter.
• Creatine, 3–5 g daily, if you want one supplement. Well-evidenced for strength, cheap, no endurance downside. It brings about a kilo of water weight in the first fortnight, which will look like the fat loss stalled. It isn’t. Start it now rather than mid-block so the weight shift doesn’t confuse your week-8 read.