In this experiment, we explored how much muscle can be built in just 90 days while minimizing fat gain. Testing three popular muscle-building diets on my brother-in-law Dayton provided clear insights into effective bulking strategies.
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Dayton, who previously dropped his body fat from around 33% to 17%, aimed to bulk up without gaining fat. Over 90 days, he went through different phases of bulking, measuring his progress with DXA scans and other metrics. Each phase presented its own challenges and gains.
During the first 30 days, Dayton practiced an accidental lean bulk, maintaining his weight around 2300 calories while training hard. He gained approximately 1.35 pounds of muscle with minimal fat gain.
The next phase, the fast bulk, increased his caloric intake to about 2800 calories. This resulted in greater muscle gains of around 1.8 pounds, but also a significant increase in fat.
For the final 30 days, Dayton returned to maintenance calories, which surprisingly helped him gain another estimated 1.1 pounds of muscle while losing some fat.
In total, Dayton gained roughly 4.4 pounds of muscle over 90 days. Fast bulking delivered the greatest muscle gains but also resulted in more fat gain. For his long-term goal of cutting to 12% body fat for summer, the lean bulk turned out to be the most effective approach. This experiment provided essential lessons on bulking according to body type and specific goals.
The results emphasize three distinct approaches to bulking:
**Maingain**: Best for those with higher body fat, eat at maintenance calories to maintain weight.
**Lean bulk**: Suitable for various levels; around a 250 calorie surplus to gain about 1% body weight monthly.
**Fast bulk**: Ideal for naturally skinny or new lifters; approximately 500 calorie surplus to gain 2-3% body weight monthly.
The journey concluded with a surprise for Dayton and his brother, introducing a new gym setup to support their continuing muscle-building goals.
By Jeremy Ethier