The Claim
Resistance training is associated with an average increase of approximately 1.53 kg in whole-body muscle mass (combined fat-free mass, lean muscle mass, and skeletal muscle mass) in healthy adult males aged 18–40 after interventions lasting 2 weeks to 1 year, indicating a consistent, measurable hypertrophic response across diverse training protocols.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
If healthy guys between 18 and 40 lift weights regularly for at least two weeks up to a year, they typically gain about 1.5 kilograms of muscle—no matter what kind of weight routine they follow.
See the scientific wording
Resistance training is associated with an average increase of approximately 1.53 kg in whole-body muscle mass (combined fat-free mass, lean muscle mass, and skeletal muscle mass) in healthy adult males aged 18–40 after interventions lasting 2 weeks to 1 year, indicating a consistent, measurable hypertrophic response across diverse training protocols.
What the research says
1 studyThis big study looked at lots of people who lifted weights and found they gained about 1.5 kg of muscle on average — just like the claim says. It didn’t matter how they trained, as long as they did resistance training for more than 2 weeks.
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.