The Claim
Untrained individuals can expect to gain approximately 1.5 kg of fat-free mass over 8–12 weeks of resistance training, with gains plateauing significantly after the first 6 months, and long-term annual gains typically below 2.5 kg in natural trainees.
What the research says
Roughly balanced
Support and challenge are close. The picture may shift as more studies come in.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
If you're new to weight training, you can expect to build about 1.5 kg of muscle in the first couple of months, but after six months, your gains slow down a lot—and after that, you’ll probably only gain less than 2.5 kg of muscle per year if you’re not using steroids.
See the scientific wording
Untrained individuals can expect to gain approximately 1.5 kg of fat-free mass over 8–12 weeks of resistance training, with gains plateauing significantly after the first 6 months, and long-term annual gains typically below 2.5 kg in natural trainees.
What the research says
1 studyStudy: Load-induced human skeletal muscle hypertrophy: Mechanisms, myths, and misconceptions
This study looks at how muscles grow from weight training and says gains are limited and slow — which matches the claim that untrained people gain about 1.5 kg in a few months and then hardly grow more after six months.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.