BCAAs
Marketing claim· human dataAlso known as: Branched-chain amino acids
Largely redundant if you already eat enough protein.
What it is
BCAAs are three of the essential amino acids — leucine, isoleucine and valine — sold as a muscle-building and recovery aid. The catch is that building muscle needs all the essential amino acids, and complete proteins already contain plenty of these three.
What the evidence shows
Muscle growth and recovery. Marketing claim· human data For anyone eating enough total protein, BCAAs add very little. The three branched-chain amino acids alone provide an incomplete signal for building muscle, and whole proteins like whey supply them anyway.
Who it suits
For a healthy person hitting their protein target, they are largely redundant. The clearest genuine uses are certain clinical situations, not everyday training.
Practical notes
A serving of complete protein — whey, or a good meal — does the same job more completely and usually more cheaply. Focus on total daily protein instead; the macro calculator helps you set a target. BCAAs are mostly a solution to a problem most trainees don't have.
Sources
Frequently asked questions
- Do BCAAs build muscle?
- For anyone eating enough total protein, they add very little. Building muscle needs all the essential amino acids; the three branched-chain ones alone provide an incomplete signal, and complete proteins like whey already contain plenty of them.
- Are they worth it during fasted training?
- The case is weak. A serving of whole protein or a complete protein source does the same job more completely and usually more cheaply. BCAAs are largely a solution to a problem most trainees don't have.
- Is there anyone they suit?
- The clearest edge cases are certain clinical situations. For a healthy person hitting their protein target, spending on BCAAs is generally poor value compared with food or whey.
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Written and reviewed by Mathew Beale — MSc Biotechnology, University of Reading.
Last reviewed: