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Bulking and cutting are the two main phases of a bodybuilding diet cycle. During a bulk, you eat more calories than you burn to provide your body with the energy it needs to build new muscle tissue. During a cut, you eat fewer calories to lose body fat while trying to preserve the muscle you built.
The key to a successful lean bulk is finding the sweet spot: enough calories to maximize muscle growth without excessive fat gain. Here are the principles:
A surplus of 200-500 calories above your TDEE is optimal for most people. Larger surpluses don't build muscle faster - they just increase fat gain.
Aim for 1.0-1.2g of protein per pound of body weight. This ensures your body has the building blocks for muscle protein synthesis.
Extra calories only build muscle if you give your body a reason to adapt. Gradually increase weight, reps, or volume in your training.
Weigh yourself weekly and aim for 0.25-0.5 kg (0.5-1 lb) gain per week for beginners. If gaining faster, reduce calories slightly.
The challenge during a cut is losing fat while preserving your hard-earned muscle. Follow these strategies:
Increase protein to 1.0-1.3g per pound of body weight during a cut. Higher protein helps preserve muscle mass when in a deficit.
Keep lifting heavy to signal your body to preserve muscle. Reduce volume if needed, but maintain intensity (weight on the bar).
A deficit of 500-750 calories is sustainable for most people. Aggressive deficits (1000+) increase muscle loss risk.
Aim to lose 0.5-1 kg (1-2 lbs) per week. Faster weight loss often means muscle loss. Trust the process.
Choosing the right phase depends on your current body composition and goals. Use body fat percentage as a guide:
If you're in the "grey zone" (12-18% for men, 20-25% for women) and happy with your physique, maintaining is a valid option. It's also good for diet breaks between phases or if you're new to tracking and want to practice before making changes.
Not all bulks are created equal. Understanding the difference between lean bulking and dirty bulking will help you choose the right approach:
| Aspect | Lean Bulk | Dirty Bulk |
|---|---|---|
| Calorie Surplus | 200-500 calories | 1000+ calories |
| Food Quality | Nutrient-dense foods | Any foods, no restrictions |
| Weight Gain Rate | 0.25-0.5 kg/week | 0.5-1+ kg/week |
| Fat Gain | Minimal | Significant |
| Cut Duration After | Shorter | Longer |
| Best For | Most people | Hardgainers, athletes |
Recommendation: Lean bulking is preferred for most people. It allows you to build muscle without spending excessive time cutting afterward. Dirty bulking may be appropriate for underweight individuals or athletes with very high calorie needs.
While total daily intake matters most, strategic nutrient timing can optimize your results:
Note: Nutrient timing has a small impact compared to total daily intake. Focus on hitting your daily targets first, then optimize timing if desired.
Bulking is a muscle-building phase where you eat in a calorie surplus to support muscle growth. Cutting is a fat-loss phase where you eat in a calorie deficit to lose body fat while preserving muscle mass. These phases are typically alternated by bodybuilders and fitness enthusiasts.
For a lean bulk, aim for a surplus of 200-300 calories above your TDEE. For a moderate bulk, target 400-500 calories above TDEE. An aggressive bulk uses 700-1000 calories above TDEE. Choose based on your goals and comfort with potential fat gain.
When cutting, protein intake should be 1.0-1.3g per pound of body weight - higher than during a bulk. This helps preserve muscle mass during a calorie deficit. For example, a 180 lb person should consume 180-234g of protein daily while cutting.
If your body fat is above 18% (men) or 25% (women), it's generally better to cut first. If your body fat is below 15% (men) or 23% (women), you're in a good position to bulk. Starting from a leaner state makes bulking more efficient.
A lean bulk uses a moderate calorie surplus (200-500 calories) with nutrient-dense foods to minimize fat gain. A dirty bulk uses a large surplus with no food restrictions, leading to more fat gain. Lean bulking is generally recommended for better long-term results.
A bulk typically lasts 3-6 months, long enough to see significant muscle gains. A cut usually lasts 8-16 weeks, depending on how much fat you need to lose. Avoid bulking past 18-20% body fat (men) or 25-28% (women).
Some people prefer to eat slightly more on training days and less on rest days (calorie cycling). This can help fuel workouts while minimizing fat gain. However, keeping calories consistent daily works well too. The most important factor is hitting your weekly targets.
When bulking, aim to gain 0.25-0.5 kg (0.5-1 lb) per week for beginners, or 0.1-0.25 kg for advanced lifters. When cutting, losing 0.5-1 kg (1-2 lbs) per week is sustainable. Faster changes often mean more muscle loss or fat gain.
Whether you're bulking or cutting, BiteKit makes tracking macros effortless. Log your meals with your voice and let AI handle the nutrition math.
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