Your macronutrient split determines whether your caloric surplus becomes muscle or fat. Here is how to calculate your optimal macros for a lean bulk, step by step, based on research.
Your Total Daily Energy Expenditure (TDEE) is the starting point. Quick estimate:
| Activity level | Multiplier | Example (80kg) |
|---|---|---|
| Sedentary + 3x training | BW × 31-33 | 2,480-2,640 |
| Moderate + 4x training | BW × 33-35 | 2,640-2,800 |
| Very active + 5-6x training | BW × 35-38 | 2,800-3,040 |
For precision: track weight for 2 weeks at normal intake. Stable weight = maintenance found.
+200-350 kcal above maintenance for a lean bulk. This provides enough energy for muscle protein synthesis without excessive fat storage. More than +500 does not build more muscle. It just builds more fat.
Morton (2018): above about 1.6g/kg a day, extra protein brought no further muscle gain in their analysis; 2.2g/kg covers almost everyone. During a bulk (caloric surplus), you can stay at the lower end (1.6-1.8g/kg) because the surplus itself provides a muscle-sparing effect. 1g protein = 4 kcal.
Essential for hormone production (testosterone), cell membrane integrity, and vitamin absorption. Going below 0.7g/kg risks hormonal disruption. During a bulk, err toward 1.0g/kg for optimal testosterone levels. 1g fat = 9 kcal.
Carbs fuel intense resistance training, replenish glycogen, and support recovery. They get whatever calories remain after protein and fat are set. 1g carbs = 4 kcal. Formula: (Total kcal - protein kcal - fat kcal) / 4.
| Goal | Protein (g/kg) | Fat (g/kg) | Carbs | Surplus |
|---|---|---|---|---|
| Lean bulk | 1.6-1.8 | 0.8-1.2 | High (rest) | +200-350 |
| Body recomp | 2.0 | 0.7-1.0 | Moderate | -200 to -300 |
| Cut | 2.0-2.2 | 0.7-0.9 | Low (rest) | -300-500 |
| Maintenance | 1.6-2.0 | 0.8-1.0 | Moderate | 0 |
Too much surplus: A 500-1000 kcal surplus does not build more muscle than 200-350. The excess becomes fat. After 12 weeks, lean and dirty bulkers gain similar muscle but dirty bulkers gain 3-5x more fat.
Neglecting protein timing: While total daily protein matters most, distributing it across 4-5 meals of 30-40g optimizes MPS throughout the day. One 120g protein meal is less effective than four 30g meals.
Cutting fat too low: Some lifters minimize fat to maximize carbs. Below 0.7g/kg, testosterone production suffers, which is counterproductive for muscle growth. Keep fat at minimum 0.8g/kg during a bulk.
As your weight increases during a bulk, your maintenance calories increase too. Recalculate every 4-6 weeks. If weight gain stalls, add 100-150 kcal (primarily carbs). If weight gain exceeds 0.5kg/week, reduce by 100 kcal.
Most people underestimate their calorie intake by 20-50%. For the first month of a lean bulk, tracking with a food scale and an app (MyFitnessPal, Cronometer) is strongly recommended. After 4-6 weeks, you develop an intuitive sense for portion sizes and can track less rigidly.
The 80/20 approach: Track protein precisely (it is the most critical macro). Estimate carbs and fat roughly. If your weekly weight is trending correctly (0.25-0.5kg gain per week), your total calories are right: the exact carb/fat split is flexible within the minimum thresholds.
Both matter. Total calories determine whether you gain or lose weight. Macros determine the COMPOSITION of that change: muscle vs fat. Hitting your protein target is particularly critical; carb/fat ratio is more flexible.
Optional. Some lifters eat +200 kcal on training days (more carbs for energy) and at maintenance on rest days. This is fine-tuning: weekly totals matter more than daily fluctuations.
Chicken breast (31g/100g), Greek yogurt (10g/100g), eggs (6g each), lean beef (26g/100g), fish (20-25g/100g), whey protein (25g/scoop). Mix animal and plant sources for complete amino acid profiles.
MUSCLE TECHNICS plans volume against a weekly set target per muscle based on your experience, tracks progressive overload, and takes volume out when your check-in shows fatigue.
Try free for 14 days →