BCAA is a very popular supplement in fitness industry and is a very hot topic nowdays. Some claims it doesn’t work and other claims it is one of the essential supplement out there.
So what exactly is BCAA?
BCAA aka Branched-chain amino acids includes three essential amino acids:
Leucine, Isoleucine and Valine, which are found in protein-rich foods such as eggs, meat and dairy products. They are also a popular dietary supplement sold primarily in powder form.
Does BCAA increase Muscle protein synthesis?
BCAA’s alone do not appear to stimulate muscle protein synthesis, at least not to a meaningful extent. Whenever we talk about muscle protein synthesis (MPS) in research, both transcription and translation must occur. To optimize MPS, all the essential amino acids (EAA’s), and quite possibly all 20 amino acids are necessary.
So does it actually work or is just another hyped supplement?
A research was performed on 24 untrained young adults. The purpose of this study was to investigate the effects of BCAA supplementation on muscle recovery from resistance exercise (RE) in untrained young adults.
Twenty-four young adults were assigned to 1 of 2 groups (n = 12 per group):
A placebo-supplement group or a BCAA-supplement group.
The groups were supplemented for a period of 5 days. On day 1 and 3, both groups underwent a RE session involving two lower body exercises (hack squat and leg press) and then were evaluated for muscle recovery on the 3 subsequent moments after the RE session [30 min (day 3), 24 h (day 4), and 48 h (day 5)].
1.Number of repetitions remained unchanged over time (time, P > 0.05)
2.while the rating of perceived exertion increased (time, P < 0.05) over 3 sets, with no difference between groups (group × time, P > 0.05)
- Muscle soreness increased (time, P < 0.05) and jumping weight decreased (time, P < 0.05) at 30 min post- exercise and then progressively returned to baseline at 24 and 48 h post-exercise, with no difference between groups (group × time, P > 0.05)
The results indicate that BCAA supplementation does not improve muscle recovery from RE in untrained young adults.
As seen above, BCAA supplementation was ineffective for increasing the number of reps, lowering the rate of perceived exertion, or decreasing soreness. Unshown is a lack of effect on jumping height and peak power output.
In summary, BCAA didn’t do jack. An important acknowledgement by the authors is that “…daily protein intake (~1.5 g/kg/day) might have been sufficient to maximize muscle recovery in our participants, masking the BCAA effects.” This is one of the rare times that this possibility is mentioned by the authors of BCAA supplementation trials.
BCAA’s are probably one of the most over- hyped dietary supplements on the market.
Who can take advantage of supplementing BCAA?
Although BCAA’s seem utterly useless, some populations may still benefit. For those following a vegan/plant-based diet and not ingesting dairy products and various meats, adding BCAA’s to each meal may augment the MPS response by increasing what was once deficient (i.e. BCAAs). This is due to the generally inferior amino acid profile of plants.
Most plant-based dieters are familiar with the term complementary proteins. Where combining different sources of plant-based protein by complementing the missing or low amino acid in each, creates a full spectrum of essential amino acids that otherwise would be deficient. However, in plants the main amino acids responsible for MPS are still relatively low and frankly not very bioavailable.17 Input BCAA supplementation.
By adding BCAA’s to the mixture of plants, the quality is enhanced and MPS is restored. Remember, in this population adding BCAA’s are just replacing what isn’t there. So, there is not an abundance, just what is needed physiologically. Akin to taking vitamins, you take what you need to regulate metabolism and physiological processes.
Similarly, adding BCAA’s to a low dose of protein may help stimulate MPS to a similar degree as higher dose of whey protein. A study reported “that a suboptimal dose of whey protein (6.25 g) supplemented with either leucine or a mixture of EAAs without leucine stimulates MPS similar to 25 g of whey protein under resting conditions.
In my opinion, based on the data at hand, if you are a healthy individual under the age of 60, BCAA’s are a waste of money. The only thing they increase is the profit of the store you bought them from. Stick with high quality protein sources, such as whey protein powders, casein protein powders, meats, fish, poultry, eggs, and dairy. Aim for 0.4-0.5g/kg per meal on average, and somewhere around 2.0-2.2g/kg total protein per day. If this is done, you are getting PLENTY of BCAA’s in your diet.
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