Researchers say that branched-chain amino acids (BCAA) aren’t doing much for gym-goers when taken by themselves. Professor Kevin Tipton explains why they’re used and why they’re not optimal.
“Amino acids are the building blocks of proteins and the special class of amino acids, known as BCAA, stimulate muscle growth response,” he said. “These supplements are considered to be an important part of the nutrition plan for many bodybuilders, weightlifters and others seeking muscle growth.”
“Our results show that the common practice of taking BCAA supplements in isolation will stimulate muscle protein synthesis – the metabolic mechanism that leads to muscle growth – but the total response will not be maximal because BCAA supplements do not provide other amino acids essential for the best response.”
Bulking up
The study used a group of trained weightlifters who took part in resistance training at the gym and followed it up with BCAA supplements in a dose equivalent to 20 grams of whey protein.
The researchers found that the BCAA supplement slightly enhanced participants’ muscle growth response when compared to a placebo. However, the muscle response more than doubled when participants took a whey protein supplement that contained equivalent amounts of BCAA and other essential amino acids.
Tipton says that those other amino acids are key to muscle growth, and it is the reason why BCAA supplements by themselves don’t deliver as much value.
“A sufficient amount of the full complement of amino acids is necessary for maximum muscle building, following exercise. Athletes interested in enhancing muscle growth with training should not rely on these BCAA supplements alone,” he said.
The full study has been published in Frontiers of Physiology.