Cutting Macro Calculator
A bodybuilding-focused tool for aggressive fat loss deficits. Includes a specialized 'Peak Week' carb manipulation schedule for contest prep or photo shoots.
About
Bodybuilding preparation is a distinct physiological challenge compared to general weight loss. The goal is not merely to lose weight, but to achieve extreme levels of leanness (often below 5-6% body fat for men, 10-12% for women) while retaining maximum muscle volume. This requires aggressive caloric deficits that must be carefully managed to prevent metabolic adaptation and catabolism.
This tool is designed for the final stages of a cut or 'prep'. It calculates a high-protein baseline to protect muscle tissue against the high cortisol environment of a deficit. Furthermore, it features a Peak Week Generator. This feature simulates the final 7 days leading up to a show or photo shoot, manipulating sodium, water, and carbohydrates to drain subcutaneous water and load glycogen into the muscle for that 'shrink-wrapped' look.
Formulas
The calculator estimates the 'Contest Deficit' TDEE. Unlike standard weight loss, prep requires variable deficits. The Peak Week loading is based on Lean Body Mass (LBM) glycogen capacity:
Standard Cutting Protein requirement is elevated:
This ensures positive nitrogen balance despite the energy gap.
Reference Data
| Day | Carb Strategy | Water Intake | Sodium | Goal |
|---|---|---|---|---|
| Monday (5 Days Out) | Depletion (0.5x) | High (6-8L) | High | Flush Aldosterone |
| Tuesday (4 Days Out) | Depletion (0.5x) | High (6-8L) | High | Deplete Glycogen |
| Wednesday (3 Days Out) | Depletion (0.5x) | High (6-8L) | High | Increase Insulin Sensitivity |
| Thursday (2 Days Out) | Loading (1.5x - 2.0x) | Moderate (4L) | Moderate | Start Glycogen Fill |
| Friday (1 Day Out) | Loading (1.5x - 2.0x) | Low (2L) | Low | Full Muscle Volumization |
| Saturday (Show Day) | Sipping / Cakes | Sipping only | Trace | Maintain Dryness & Pump |
| Standard Cutting Ratios | Protein | Fats | Carbs | Notes |
| Early Prep (12 weeks out) | 35% | 20% | 45% | Fuel training volume |
| Mid Prep (6 weeks out) | 45% | 20% | 35% | Increase protein sparing |
| Close (2 weeks out) | 50% | 15-20% | 30% | Max deficit capability |