Health⏱ 5 min read
How to Set Macros for a Cutting Phase (Fat Loss with Muscle Retention)
Cutting requires a calorie deficit, but the macro split determines how much muscle you keep. Here is the evidence-based calculation for a successful cut.
A poorly planned cut leaves you lighter but weaker and flabbier than expected — because muscle is lost alongside fat. Getting the macros right during a deficit is at least as important as the calorie target.
Setting Calorie Deficit for Cutting
Recommended deficit rate:
0.5-1% of body weight per week = optimal fat loss without excessive muscle loss
For 80kg person:
0.5% = 0.4 kg/week = approximately 400 kcal/day deficit
1.0% = 0.8 kg/week = approximately 800 kcal/day deficit
Start with 0.5% for first 4 weeks, adjust based on results.
Deficits larger than 1,000 kcal/day significantly increase muscle loss risk.
TDEE example: 80kg, moderately active = 2,800 kcal/day
Cutting target (500 kcal deficit): 2,300 kcal/day
Macro Priority Order During a Cut
1. PROTEIN — Set highest priority: 2.2-2.8g per kg body weight
Higher than maintenance because protein spares muscle in a deficit.
Research supports up to 3.1g/kg during aggressive cuts.
2. FAT — Minimum floor: 0.7-1.0g per kg body weight
Do not go below 0.7g/kg -- fat is essential for hormone production.
Testosterone drops significantly on very low fat diets.
3. CARBS — Fill remaining calories after protein and fat are set.
Carbs are prioritised around training for performance.
Example: 80kg, 2,300 kcal cutting target
Protein: 80 x 2.4 = 192g = 192 x 4 = 768 kcal
Fat: 80 x 0.9 = 72g = 72 x 9 = 648 kcal
Remaining calories for carbs: 2,300 - 768 - 648 = 884 kcal
Carbs: 884 / 4 = 221g
Final targets: 192g protein | 221g carbs | 72g fat | 2,300 kcal
Protein Timing During a Cut
In a calorie deficit, protein timing becomes more important:
Pre-workout protein (within 2h): prevents catabolism during session
Post-workout protein (within 2h): initiates repair and muscle protein synthesis
Evidence for resistance training in a deficit:
Training 3-4x/week is the most powerful muscle-sparing intervention.
Without training, even optimal protein cannot prevent significant muscle loss.
Minimum training to preserve muscle during cut:
2 sessions/week of compound resistance training (squat, hinge, push, pull)
Better: 3-4 sessions/week with progressive overload
Rate of Progress and Adjustments
Expected results on well-planned cut (per week):
Scale weight: down 0.3-0.6 kg/week
Body fat %: down 0.2-0.5%/week
Strength: minimal change or slight decrease (acceptable)
Warning signs of too aggressive a cut:
Strength dropping more than 5-10% on main lifts
Significant fatigue, poor sleep, mood changes
Weight dropping more than 1% per week
If this happens: increase calories by 150-200 kcal/day (mainly carbs)
Reassess after 2 weeks