The Benefits of BCAA Supplementation

UK Fitness Pro
UK Fitness Pro
· 5 min read
Personal trainer discussing the benefits of BCAA supplementation.

The Benefits of BCAA Supplementation

Branched chain amino acids (BCAAs; leucine, isoleucine, valine) are “essential” amino acids. This simply means the body is unable to synthesise them in sufficient quantities, and so they need to be consumed. Since BCAAs constitute 35% of the essential amino acids in muscle proteins (1), it’s perhaps unsurprising that BCAA supplementation has been consistently linked to increased athletic performance. Let’s take a look at five types of athlete that science says can benefit from BCAA supplementation

Cycling and the Benefits of BCAA Supplementation

Cyclists can enjoy the benefits of BCAA supplementation.

In a study published in Amino Acids (2), researchers asked trained cyclists to consume either a BCAA supplement or a placebo, taken for 10 weeks at 12 grams per day. Before and after the 10-week period, the participants completed the Wingate test, an assessment of anaerobic power where the individual pedals as hard as they can for 30 seconds on a cycle erg. While no substantial improvements were seen in the placebo group, the BCAA group exhibited a 4% increased in mean power and a massive 20% increase in peak power.                                    

Running and the Benefits of BCAA Supplementation

Runners can enjoy the benefits of BCAA supplementation.

BCAAs seem to also benefit runners. Researchers in Taiwan (3) observed that national-level endurance runners ran significantly faster over 5,000 metres if, an hour before running, they consumed BCAAs (mean time: 17 minutes, 45 seconds) compared to a placebo (mean time: 18 minutes, 20 seconds). Likewise, they were significantly faster over 10,000 metres after BCAA supplementation (mean time: 34 minutes, 52 seconds) compared to placebo (mean time: 36 minutes, 15 seconds).                                        

Swimming and the Benefits of BCAA Supplementation

Swimmers can enjoy the benefits of BCAA supplementation.

As well as endurance, BCAAs have been linked to improved performance when undertaking high-intensity interval training (HIIT). An article published in Nutrients (4) describes the effects of BCAAs on lap times among national- and international-level young swimmers. When the participants took BCAAs an hour before eight 50-metre sprints (with 3-minute rests in between) they were significantly faster than when they took a placebo. On average, laps completed after BCAA consumption were almost half a second faster. This might not seem like much, but in the 50-metre freestyle finals at the Rio Olympics only a hundredth of a second separated silver from gold.                                                             

Tennis and the Benefits of BCAA Supplementation

Tennis players can enjoy the benefits of BCAA supplementation.

BCAAs can also minimise the cognitive decline associated with fatigue. Researchers in Taiwan (5) assessed the effects of BCAAs on perceptual–motor skills among national-level tennis players. In tennis, these skills refer to, “the ability to acquire information about the opponent’s body and racquet movements, then select and execute appropriate actions”. To measure this ability, the researchers had the player stand at one end of the court and placed an examiner and a serving machine at the other. Once a ball was served, the examiner randomly walked to one side of the court and the player had to return the ball to the opposite side. When well rested, players managed this with near-perfect accuracy, regardless of whether they had taken BCAAs or a placebo. However, when tested again after two hours of match play, the accuracy of players that had taken the placebo plummeted (69%), while the accuracy of those that had taken BCAAs remained almost flawless (94%). 

Football and the Benefits of BCAA Supplementation

Footballers can enjoy the benefits of BCAA supplementation.

Additionally, BCAAs can benefit perceptual–motor skills among football players. An article in Applied Physiology, Nutrition, and Metabolism (6) describes how researchers had professional football players run for 90 minutes on a treadmill and respond, using hand-held buttons, to various stimuli presented at intervals throughout; if they saw a red light, they pressed the right button; if they heard a sound, they pressed the left; and if they saw a green or a yellow light, they pressed neither. Compared to when they took a placebo, the players reacted to the stimuli 10% faster if they took a 7-gram BCAA supplement an hour before the test, suggesting BCAAs might help footballers to respond more effectively to events when involved in real matches. 


The benefits of BCAA supplementation include increased anaerobic power, endurance, and perceptual–motor skills. Some of these benefits might be due to BCAAs activating enzymes that are key to muscle synthesis (7), while others could result from BCAAs minimising exercised-induced increases in serotonin in the brain, which are associated with fatigue (8). Whatever the precise mechanisms, it’s clear that BCAA supplementation can benefit a range of athletes in a number of ways. So, if you’re looking to get the most out of your workouts (and maybe add a little flavour to your water), why not give BCAAs a try? 

About the Author

As well as BSc, MSc, and PhD degrees in life science subjects, James Roberts has over 10 years of experience in strength and endurance training. He loves to write in order to share his expertise in healthy eating, training, and supplementation

An expert on the benefits of BCAA supplementation.

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