By Erick Avila

Amino acids are commonly referred to as the “building blocks” of the body because our body uses them to build everything from hair and skin to muscles. The BCAAs are probably the most popular group of amino acids because of their various benefits. If you look around your gym, you’ve likely seen a few people sipping away at a jug full of bright colored liquids. Chances are they’re drinking BCAAs.

Let’s go over what exactly BCAAs are and the best times to take BCAAs so you can benefit from them.

What are BCAAs?

BCAAs are branched chain amino acids. They’re given this name because, compared to other types of amino acids, they have a unique chemical structure that resemble tree branches. Unlike other amino acids that are broken down in the liver, BCAAs mostly bypass the liver for rapid absorption into the blood stream.[1] BCAAs make up 3 of the 9 essential amino acids; certain amino acids are deemed “essential” because our bodies can’t make them, but we need them to function properly.

BCAAs are comprised of three amino acids: leucine, isoleucine, and valine. Each of these amino acids has unique functions in the body.

Leucine: stimulates muscle protein synthesis [2]
Isoleucine: plays a role in glucose metabolism [3]
Valine: plays a role in tissue repair [4]

2:1:1 BCAA ratio

The 2:1:1 ratio refers to the preferred ratio of leucine, isoleucine, and valine in a BCAA compound. BCAAs can be found in various ratios in different dietary supplements. XTEND® uses BCAAs in the 2:1:1 ratio, which is a ratio commonly used in clinical studies examining the effects of BCAAs.

What are the benefits of BCAAs?

Reduce exercise induced muscle soreness*

Resistance training causes small damages to our muscle fibers that provoke our body to adapt and build bigger stronger muscles. This style of training is also commonly associated with delayed onset muscle soreness (DOMS). Because of their role in muscle protein metabolism, BCAAs have been researched for their potential to mitigate exercise induced muscle soreness. Two separate systematic reviews found when BCAAs were consistently supplemented with at appropriate dosages, they have a potential beneficial role for reducing muscle damage compared to placebo. [5,6]

Fatigue reduction during exercise*

BCAAs compete with the amino acid tryptophan for uptake in the brain.[7] Tryptophan is an amino acid that plays a role in the production of the hormone serotonin, a hormone that promotes sleepiness*.[7] Researchers have investigated the impact of supplementing with BCAAs before fatiguing exercise. In a systematic review of BCAA supplementation before or during endurance exercise, the researchers concluded that they observed less muscle damage, perceived effort, fatigue, and pain sensation in the groups supplementing with BCAAs. *[8]

BCAAs and intermittent fasting

Intermittent fasting is a dietary approach that involves zero calorie or very limited calorie intake (usually less than 25% of one’s daily intake) during selected periods of time. [9] Approaches to fasting usually range from 16 hour fasts to whole day fasts.[9] Because BCAAs aren’t a whole food, some people wonder whether they can supplement with BCAAs while intermittent fasting. This will depend on the strictness of one’s fast. For a fast where individuals can consume a limited calorie intake, BCAA supplementation would be appropriate.

What’s the best time to take BCAAs?

To get the most out of BCAAs, use them before or during a workout to support reduced fatigue and delayed onset muscle soreness*.

Other popular times to take BCAAs include after a workout with a complete protein to support recovery, alongside a meal low in BCAAs to boost intake of key amino acids like leucine, and any time of the day that you want refreshing amino based hydration rather than a sugary beverage*.

How much BCAAs should I take?

In one of the meta-analysis studies that showed BCAAs have a beneficial effect for DOMS, the researchers recommended > 200 mg per kg per day of BCAAs for greater than 10 days.[5]

If you don’t feel like calculating a daily BCAA amount, we’ve made the process easy for you, just take 2 scoops of XTEND® for a total of 14 grams of BCAAs a day. The XTEND® formula has been clinically researched in 2 separate clinical trials at 2 scoops a day. These studies showed that XTEND® BCAAs had beneficial effects on body composition alongside diet and exercise. [10,11]


*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.