If you want to know why this works — why insulin governs fat storage, why frequent carbohydrate intake blocks fat oxidation, why "eat less, move more" fights physiology — read Gary Taubes. We won't repeat his case here. Start with Why We Get Fat, then Good Calories, Bad Calories, then The Case Against Sugar. After that, the protocol below makes sense on its own terms.
The cycle
The principle: sustained calorie deficits drive the body to defend itself — thyroid output falls, leptin drops, hunger hormones rise. After 2–3 weeks of continuous restriction, the same intake stops producing fat loss. The 9-day maintenance phase is not a "cheat" — it is a deliberate metabolic reset that lets the next deficit phase actually work.
Phase 1's low-carb (0.33 g/kg ≈ 28 g/day for an 85 kg climber) keeps insulin low and fat oxidation running. Phase 2's normal-carb (1 g/kg ≈ 85 g/day) refills muscle glycogen, restores energy, and signals "no famine here" to the metabolic regulators that would otherwise downshift.
What this actually produces
I am the protocol author and the test subject. The numbers below are from my own DEXA-tracked cycles, where I separated pure fat loss from glycogen, water, and muscle changes — which is what we care about. Scale weight in week 1 drops more than these figures because of glycogen depletion; that's not fat and we don't count it.
Your plan
Your plan
Phase 1 — Deficit (12 days)
Burn the fatLower carbs, adequate protein, deliberate calorie deficit. Your body relearns to access stored fat instead of waiting for the next meal. Energy will dip for the first 5–10 days; this is normal and passes.
Your macros
How to actually do it
- 0.33 g carbs/kg body weight/day. Below ~30 g for most. No bread, no rice, no fruit (except small berries). Leafy greens and cruciferous veg are essentially free.
- ~2 g protein/kg body weight/day. Preserves muscle under deficit. Lean meat, fish, eggs.
- Fill the rest with fat, not carbs. Olive oil, avocado, fatty fish, the cream in your morning coffee.
- Electrolytes are critical. Sodium, potassium, magnesium. Add an electrolyte mix like Hydrate to your water bottle, or salt your food deliberately. Most "low-carb flu" is actually low electrolytes.
- Sleep ≥ 7 hours. Sleep debt sabotages everything. Power-nap to catch up if you start early.
- Walk daily. Avoid exhaustive cardio in weeks 1–3. Easy aerobic only until you're fat-adapted; then ramp up.
- Expect to feel 10% weaker for the first 1–2 weeks. This is real and unavoidable. Strength returns after fat-adaptation completes.
Phase 2 — Maintenance (9 days)
Deliberately plateauEat at maintenance. Bring carbs back to 1 g/kg. The point is to disrupt the metabolic adaptation that would otherwise stall the next deficit phase. Do not panic if scale weight ticks up 1–2 kg — that's glycogen and water, exactly what we want refilled before the next 12 days.
Your macros
How to actually do it
- Eat to maintenance. Your TDEE is the target — neither above nor below. No deficit, no bingeing.
- Normal-quality carbs, not junk. Rice, oats, sweet potato, fruit. Not pastries and pasta.
- Protein stays high (1.6 g/kg is plenty — the body's not fighting catabolism anymore).
- Training can ramp. This is when you do the harder cardio and strength work — your glycogen is refilling and you can actually push.
- Track the same metrics (waist, weight, energy) — you're looking for plateau, not loss. That's success.
Phase 1 meal template
| Meal | Option 1 | Option 2 | Option 3 |
|---|---|---|---|
| CoffeeMorning | Black coffee + 15 ml cream | Black coffee only | Coffee + pinch of salt |
| Meal 1Midday | 150 g chicken breast · 70 g avocado · 120 g courgette · salt | 150 g extra-lean beef mince · 120 g cauliflower · 1 tsp olive oil | 150 g tuna steak (grilled) · leafy greens · lemon + salt |
| Meal 2Afternoon | 1 tin tuna in water · 120 g asparagus · 1 tsp olive oil | 140 g salmon steak · 120 g spinach · no added fat | 150 g chicken breast · 120 g courgette · salt |
| Meal 3Evening | 4-egg-white omelette · 120 g wilted spinach · ≤20 g onion | 120 g tuna steak · leafy greens · mustard or herbs | 130 g extra-lean beef mince · courgette · salt |
21-day tracker
| Day | Phase | Body weight (kg) | Waist (cm) | Net carbs (g) | Protein (g) | Calories | Energy / notes |
|---|
Track waist measurement, not just scale weight. Scale weight is contaminated by glycogen and water swings, especially in week 1 and again at the start of every Phase 2. Waist is the honest fat-loss proxy.
This protocol isn't for everyone
Don't follow this if you are pregnant or breastfeeding; on insulin or sulfonylureas for diabetes (the medication dose assumes carb intake); have a history of disordered eating; or are mid-way through an active endurance training block where glycogen replenishment matters daily. If any of those apply, talk to a doctor or sports dietitian who knows your situation — this page is general protocol, not personal medical advice.