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When To Take BCAA’s?

When To Take BCAA’s?

Reviewed By Kyle Crowley MSc Sports Nutrition

Branched-chain amino acids or BCAA’s for short, are extremely popular sports nutrition supplements with many benefits, especially when it comes down to muscle growth and recovery. However, in order not to be the ‘all the gear no idea’ guy, It’s essential that you understand when and how to take BCAA’s to get the very most it of each and every scoop you take.

What Are BCAA’s?

To get us on the route of understanding how to use them, we first need to get to grips with what they actually are. We’ll keep this one short and sweet for you. So, getting down to specifics. There are 20 different amino acids in our body and makeup protein, although not all are the same, that being, some are produced by our body naturally and some must be obtained through the food we eat.

Of the nine amino acids that make do naturally make, three are the BCAA’s we find in our favourite supplements. These include leucine, isoleucine and valine.

Are BCAA’s Worth It?

BCAA’s like all sports nutrition products have been subject to a lot of scientific studies, to see if all the claims really add up, we’ve been through, and find a couple to give you some confidence in taking BCAA supplements.

Claim: BCAA’s increase muscle growth

Evidence: A study performed on two groups looked at muscle protein synthesis rates after taking part in resistance training. Those who consumed 5.6g of BCAA’s post-workout had a 22% increase in muscle protein synthesis compared to those who had taken the placebo drink. (Jacksman et al. 2017)

Claim: BCAA’s decrease muscle soreness

Evidence: One study looked at muscle soreness of individuals pre-workout before a squat, and delayed onset muscle soreness. The results distinguished that those who consumed a BCAA supplement drink compared to the placebo group reported having less muscle soreness. (Shimomura 1 et al. 2010)

Claim: BCAA’s reduce exercise fatigue

Evidence: During exercise BCAA’s are used and levels fall. When these levels fall, another amino acid called tryptophan in your brain increases. This tryptophan is converted into serotonin, a chemical that is known for contributing to the development of fatigue. By consuming BCAA’s helps to minimise tryptophan in the body (Shimomura 2 et al. 2004).

How Much BCAA Should I Take?

The main reason for consuming a BCAA supplement is to help trigger muscle protein synthesis to repair and rebuild muscles after a training session.

If you’re getting adequate amounts of protein in your diet (e.g 1g per 1 pound of muscle mass), whether that be from protein shakes or food then BCAA’s may not be needed. However, we all live busy lives, and maintaining high levels of protein in your diet can be difficult, especially at weekends while you’re out partying, this is where BCAA’s come in to help boost that all-important muscle protein synthesis and help build those biceps.

Studies have looked at how much BCAA should be consumed to make sure that we stimulate muscle protein synthesis, for example after 30 days of BCAA supplementation at 14g/day individuals showed a significant increase in muscle mass and strength in untrained subjects (Candeloro et al. 1995), whereas a study using only 5g of BCAA supplementation showed no improvements in body composition of muscle mass (Spillane et al. 2012).

Furthering this a study performed by Schena et al (1992), also found that a higher dosage of 10g of BCAA supplementation also increased fat-free mass by 1.5% during a 21-day trek. This indicates that a higher dosage of BCAA is the best way to stimulate muscle protein synthesis in order to gain more muscle mass and help recovery.  

BCAA’s can be found in different forms from powders to pills and can be taken up to 3 times a day, depending on your own dosage. They can be mixed with other supplements or taken on their own, though it’s important to follow the manufacturer’s directions often shown on the reverse of BCAA pouches or tubs, as some BCAA supplements can vary in their ratios and potency.  

When Should I Take BCAA’s?

BCAA levels usually peak around 30 minutes after consuming the supplement, though studies have struggled to determine the best exact time to consume (Howatson et al. 2012), though it often depends on the type of blend you consume and the additional ingredients these contain.

It’s often described as the ‘window’ to take your supplements 30-60 minutes after working out, due to your body being in it’s the most absorbable state and needing certain macronutrients to replenish what has been used.

We would advise taking them around a workout – either just before, intra workout(during) or post workout.

Worth noting however, following new technology and advancements in understanding this window, some say it may be as long as five hours after exercise (Schoenfield et al. 2017 & Aaragon & Schoenfield 2013) so don’t worry too much if your forget to chug your BCAA’s as you walk out the gym. Though, having them in a powdered form makes this much easier to consume in your own time and taking them directly after your workout saves you from forgetting during the night.  

Taking BCAA Pre-workout

There are many BCAA blends that contain pre-workout ingredients. For example, take THE PROTEIN WORKS, Amino-NRG, contains BCAA’s, green tea extract, beta alanine, citrulline malate and caffeine, helping to improve mental focus and reduce tiredness and fatigue.

Taking these types of BCAA blends help to flood your muscles with amino acids helping to assist your workout, but also giving you the energy to last a full training session. It’s important to note here that taking this type of BCAA blend late at night is not recommended as the caffeine content can stop you from sleeping.

However, consuming normal BCAA blends is also highly recommended for pre-workout as it allows your body to maintain high BCAA levels through your workout, whilst also making sure that you stay hydrated too when mixing it with water.

There are very few studies looking at the difference of consuming BCAA’s as a pre-workout and post-workout, as the majority have simply looked at the benefits after an intense workout.

However, in a study performed by Miyazaki et al. (2018), looked at BCAA supplement timing on exercise-induced soreness and damage, finding that those who consumed 10g of BCAA pre-workout experienced less muscle soreness after exercise and lower blood markers of muscle damage than those who consumed the 10g of BCAA postworkout.

There are lots of limiting factors, for example, how hard the individual has trained, so these need to be taken into consideration when looking at what time you wish to take a BCAA supplement.

Taking BCAA Post-workout

Taking BCAA post-workout really is where it comes into its own, as the supplement itself is aimed towards recovering muscles once depleted after a hard training session, rather than boosting your energy.

It’s one of the reasons why we also consume whey protein post workout, to simply supply your muscles with amino acids to help them recover, BCAA also does this but in a more concentrated format. This means that the amino acids can be broken down and absorbed much quicker than what is found in protein, helping to speed up your recovery rate.

As we’ve explained a little bit of detail above, BCAA contains amino acids leucine, isoleucine and valine. More commonly known is leucine due to its effects of protein synthesis and muscle protein synthesis. Now if you didn’t already know, these two terms are incredibly important when it comes down to building and repairing muscles after hard training sessions.

Muscle protein synthesis is the naturally occurring process where protein is produced to repair muscle tissue damage, this is how muscle strength and size is built, and by stimulating muscle protein synthesis enables you to accelerate your growth, improve recovery and overall improve athletic performance.

By taking BCAA supplements post-workout, it gives your body the best chances of recovery and reducing the chances of the dreaded delayed onset muscle soreness. For example, following a study looked at muscle protein synthesis rates after the consumption of a BCAA drink. Those who consumed 5.6g of BCAA’s post-workout had a 22% increase in muscle protein synthesis than those who had consumed a placebo drink. (Jacksman et al. 2017)

BCAA Before Bed?

One area that many athletes and gym goers fail to optimise is their ‘before bed’ nutrition. During this time your body is usually starved from an energy source and as such why you go into a catabolic state during sleep. This isn’t such a bad thing as it’s an effective way of losing weight as your body uses its fat stores for energy. However, it also breaks down muscle too. Which after working hard in the gym all week is the last thing you want to be happening while you dream the night away.

During this catabolic state while sleeping, BCAA levels in the body can drop off within the first few hours. By consuming BCAA’s before going to sleep, it allows your body to have a drip feed of amino acids, triggering muscle protein synthesis to reduce recovery rates and build muscle mass too. Triggering protein synthesis may also help your body use its fat stores of the first source of energy rather than muscle too. So that’s building muscle and losing fat, what isn’t there to like about BCAA’s?

The rule of not consuming anything after 8pm is now in the past, but that doesn’t mean consuming a big meal or heavy protein shake is the way forward, and as such why many individuals opt for BCAA’s instead.

Consuming another meal late at night instead of BCAA’s means the chances of missing your macros and feeling full and bloated. Fair enough if you’re trying to bulk then added calories are needed, but if looking to slim down for summer it’s something that you need to be careful of, and why taking BCAA’s instead is the much better option.  


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