The Claim
In healthy, resistance-trained young men consuming 1.8 g protein per kg of body weight daily, 10 g/day of leucine supplementation for 12 weeks provides no additional benefit to increases in leg-press one-repetition maximum strength or vastus lateralis muscle cross-sectional area beyond resistance training alone.
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 you're a young guy who lifts weights and already eats enough protein, taking extra leucine pills for 12 weeks won't make you stronger or build more muscle in your thighs than just lifting weights by itself.
See the scientific wording
In healthy, resistance-trained young men consuming 1.8 g protein per kg of body weight daily, 10 g/day of leucine supplementation for 12 weeks provides no additional benefit to increases in leg-press one-repetition maximum strength or vastus lateralis muscle cross-sectional area beyond resistance training alone.
What the research says
1 studyStudy: Leucine Supplementation Has No Further Effect on Training-induced Muscle Adaptations
The study gave some guys 10 grams of leucine daily while they lifted weights, and others got a fake pill — both groups got equally stronger and built the same amount of muscle, so the leucine didn’t help any more than just lifting weights alone.
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.