Leucine is the amino acid that most directly activates the mTOR pathway, the central biological mechanism of muscle building — without enough leucine, muscle protein synthesis stays sub-optimal even when other nutrients are present. The 4:1:1 ratio doubles the leucine dose compared with the common 2:1:1 ratio, for a stronger anabolic stimulus — particularly suited to bulking, cutting (where muscle preservation is critical) and intensive recovery.

BCAAs support muscle protein synthesis via the leucine-driven mTOR pathway; provide an anti-catabolic effect during intense or prolonged exercise by limiting the breakdown of muscle protein; are oxidised directly in the muscle for on-the-spot energy; and compete with tryptophan for entry into the brain, which may help delay the perception of central fatigue during exercise.

Take 5 g per serving, dissolved in 200–300 ml of water, fruit juice or your protein shake — before training to prepare the muscles, during long sessions (over 60 minutes) to sustain amino acid levels, or after training to kick-start recovery. A 350 g pot gives 70 doses, over two months at one serving a day.

Do not exceed the recommended daily dose. Not a substitute for a varied, balanced diet. Store in a cool, dry place away from light.

Weight-training and bodybuilding practitioners in a bulking or cutting phase, endurance athletes wanting to preserve muscle mass, CrossFit and HIIT practitioners, people on a calorie-restricted diet, and vegetarian or vegan athletes whose dietary BCAA intake may fall short.

What is the difference between BCAA 4:1:1 and 2:1:1?

The 4:1:1 ratio contains twice the leucine of the 2:1:1 ratio, for a stronger stimulation of muscle protein synthesis — generally recommended for athletes seeking maximum anabolic support, while 2:1:1 remains a solid general-purpose choice.

Are BCAAs useful when cutting?

Yes — during calorie restriction the body is more likely to draw on muscle reserves for energy. BCAAs provide an anti-catabolic signal that helps protect lean mass while supporting training performance despite the deficit.

Herba Barona is an independent specialist supplement shop in the heart of Paris — established in 2006. What you order is genuinely on our shelves: we ship from our own stock, with no dropshipping and no long waits.

Visit us at 10 rue Théophile Roussel, Paris 12 — or use Click & Collect and pick up your order in-store. We also deliver across France and Europe. Friendly, expert advice in English from our team.

Where is the shop?

Herba Barona is at 10 rue Théophile Roussel, 75012 Paris — a two-minute walk from Ledru-Rollin (line 8), close to Bastille. Open Tuesday to Saturday, 9:30 am–6:30 pm.

Can I order online or collect in store?

Yes. We ship across France and Europe under the same conditions as our French store, or choose Click & Collect to pick up your order for free at our Paris shop.