There’s no such thing as a secret weapon for building muscle faster, but taking branched-chain amino acids (BCAAs) during your workout might just be the closest thing. That’s because these essential building blocks of protein prevent muscle tissue from being broken down, and encourage muscle protein synthesis to stimulate the creation of new muscle mass.

What are BCAAs?

Amino acids in general are commonly described as the “building blocks” of protein. More than 500 types are known but only a few are instrumental in protein synthesis – the process by which new muscle tissue is formed – and so considered essential nutrients for our diet. Most of these can be synthesised by your body from other compounds, but there are nine amino acids that cannot be, we means we have to consume them from food (or supplements).

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The nine amino acids we can’t synthesise are phenylalanine, valine, threonine, tryptophan, methionine, histidine, leucine, isoleucine and lysine. And it’s the last three on the list which are of the most interest to you if you’re training to build muscle mass, because they are collectively known as the branched-chain amino acids and play a major role in the formation of new muscle tissue – among other performance benefits. Here’s what you need to know about how they work.

What do they do?

Athletes and bodybuilders have long used BCAAs for increased protein synthesis, increased muscular hypertrophy, improved exercise recovery, increased muscle endurance, improved glucose disposal, increased energy and increased gluconeogenesis (the metabolic process in which glucose is derived from non-carbohydrate sources). Some research even suggests that they are beneficial in playing certain sports because they improve hand-eye co-ordination.

Do I need them?

Because amino acids are the building blocks of protein, if you eat a high-protein diet it’s likely you’re consuming them already. Red and white meat, fish and eggs are especially good sources, but to get the full beneficial effects of stimulating muscle protein synthesis and preventing muscle mass breakdown – which happens when you weight train – you should consider adding a BCAA supplement to your training nutrition plan. You might also want to take BCAAs when you do any fasted cardio training to limit muscle catabolism.

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The ideal way to supplement with BCAAs is with a product that offers a 2:1:1 ratio of leucine to isoleucine and valine – that’s been proven to be the most effective combination for performance, muscle maintenance and growth benefits. As for timing, mix 10g of BCAA powder with 200ml of water and shake and sip before and/or during your session to keep your muscles fully fuelled.