Does leucine make you stronger or bigger?
Effects of leucine intake on muscle growth, strength, and recovery in young active adults: a systematic review of randomized controlled trials
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Leucine supplementation had no effect on muscle recovery markers like creatine kinase or soreness, despite strong biological plausibility.
Many athletes take leucine post-workout hoping to reduce soreness and speed recovery—this study shows it doesn’t help, even though animal and cell studies suggest it should.
Practical Takeaways
Skip leucine supplements if you’re already consuming 1.6–2.2g of protein per kg of body weight daily—your food is doing the work.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Leucine supplementation had no effect on muscle recovery markers like creatine kinase or soreness, despite strong biological plausibility.
Many athletes take leucine post-workout hoping to reduce soreness and speed recovery—this study shows it doesn’t help, even though animal and cell studies suggest it should.
Practical Takeaways
Skip leucine supplements if you’re already consuming 1.6–2.2g of protein per kg of body weight daily—your food is doing the work.
Publication
Journal
Nutrire
Year
2025
Authors
Geison Rivera-Bermúdez, María Fernanda Pizarro-Segura, Dayana Quesada-Quesada, M. Segura-Buján, Reza Zare, G. Gómez, Alan A. Aragon
Related Content
Claims (6)
Taking leucine supplements won’t help young athletes build more muscle, get stronger, or recover faster—even though leucine is known to trigger a muscle-growth signal in the body.
Taking extra leucine — a supplement found in protein — won’t help healthy, fit young adults build more muscle, get stronger, or recover faster from workouts, no matter how much they take or how long they take it, for up to 12 weeks.
Taking leucine — a protein building block — might turn on muscle-building signals in your muscles, but if you're already training and eating enough protein, it won't actually make you stronger, bigger, or recover faster.
Taking leucine supplements won't help healthy, trained young adults recover faster after a tough workout, based on how sore they feel, how much strength they lose, and a blood marker for muscle damage.
Taking extra leucine (a protein building block) won’t help healthy, trained young adults build more muscle from weight training, even if the dose is big enough to trigger a key muscle-growth signal in the body.