BCAA

What are BCAAs?

The term BCAAs is another name for the group of branched-chain amino acids, which includes the three amino acids leucine, isoleucine and valine. The name "branched-chain amino acids" is derived from the particular molecular structure of these amino acids. BCAAs belong to the category of essential amino acids that the body cannot produce itself from other amino acids, which means that the branched-chain amino acids must be supplied through food or in the form of supplements. BCAAs are found in the highest concentration in muscle tissue and make up over 30% of muscle protein. Unlike all other amino acids, the branched-chain amino acids are not metabolized in the liver but directly in the muscle tissue and can therefore contribute to meeting the energy requirements of the muscles during intense muscular exertion. Therefore, especially for athletes often makes sense to buy BCAA supplements.

For what reasons are BCAAs supplemented?

During intense training sessions, in addition to carbohydrates, branched-chain amino acids are also drawn from the amino acid pool of the muscles for the purpose of supplying energy to the muscles. Post-exercise supplementation with BCAAs can promote recovery and prevent catabolic muscle breakdown for the purpose of replenishing muscle BCAA stores. As an added bonus, BCAAs can reduce muscle soreness after exercise.

In addition, BCAAs, and in particular the branched-chain amino acid leucine, stimulate protein synthesis after exercise, thereby generating an anabolic environment that promotes muscle mass building. BCAAs supplemented before and during exercise can also enhance exercise performance by providing an additional source of energy to hard-working muscles and delaying the onset of fatigue. As part of a calorie-restricted diet, BCAAs are often used to prevent a diet-induced catabolic environment in the body and associated muscle mass loss. As an added bonus, BCAAs can stabilize blood sugar levels during dieting and reduce hunger and appetite.

What are the main benefits of BCAAs?

• Support and promote muscle recovery after exercise
• Stimulation of protein synthesis and promotion of muscle building
• Increasing aerobic and anaerobic training performance
• Delaying the onset of muscle exhaustion
• Anticatabolic effect and prevention of muscle loss during a calorie-restricted diet.
• Reduction of muscle soreness after exercise
• Reduction of hunger and appetite during a calorie-restricted diet

Do BCAAs have side effects?

Harmful side effects are not known. BCAAs are found in protein-rich foods and are completely natural as the main component of our muscles. Of course, excessive consumption should be avoided.

Dosages of BCAA Supplements

There are different dosages of the Branched-Chain-Amino-Acids. The ratio of the individual amino acids is always specified in supplements. The dosage always refers to the ratio of the BCAAs to each other and is basically given according to the following scheme:

Leucine : Isoleucine : Valine

Most BCAA supplements are dosed as follows:

• 2:1:1
• 4:1:1
• 8:1:1

The relatively high proportion of leucine can be explained by the fact that leucine has a notable influence on protein synthesis compared to the other two amino acids and is therefore particularly important for muscle building.

Isoleucine Leucine Valine

The amino acids isoleucine, leucine and valine are essential for the body and have a typical branching in their structural chains. Therefore, they are called branched-chain amino acids. All three belong to the neutral amino acids, they can behave both basic and acidic.

Isoleucine, leucine and valine are an important source of energy for the muscles. They reduce the breakdown of proteins and promote the synthesis and storage of proteins during increased physical stress. Because of this effect, they are called stress amino acids. Isoleucine, leucine and valine are not metabolized in the liver like other amino acids. They go directly to the muscles where they are used by muscle cells as an important source of energy. They also appear to protect muscle glycogen stores. During increased physical stress, for example during injury, illness and surgery, the body breaks down proteins to a greater extent. Isoleucine, leucine and valine help to reduce this breakdown. They also make it easier to synthesize and store proteins in the body. The branched-chain amino acids are also transported to the brain, but compete with the amino acids tyrosine and tryptophan for absorption there. Leucine also stimulates the release of insulin in the pancreas. This in turn promotes protein synthesis and hinders protein breakdown. Valine is a glycogen-active amino acid. It plays a role in the biosynthesis of pantothenic acid and penicillin and is important for nerve and muscle functions.

The best food sources for BCAAs

Fortunately, there is a wide range of foods that contain BCAAs. Some foods with the highest BCAA content include:

• Meat, poultry, fish: 3 to 4.5 grams per 3 oz (84 grams)
• Beans and lentils: 2.5 to 3 grams per cup
• Milk: 2 grams per cup (237 ml)
• Tofu and tempeh: 0.9 to 2.3 grams per 3 oz (84 grams)
• Cheese: 1.4 grams per 1 oz (28 grams)
• Eggs: 1.3 grams per large egg
• Pumpkin seeds: Ewa 1 gram per 1 oz (28 grams)
• Quinoa: 1 gram per cup
• Nuts: 0.7 to 1 gram per 1 oz (28 grams)

How do BCAAs work?

BCAAs make up a large portion of the amino acids in the body's amino acid pool. Together, the three BCAAs represent about 35 to 40% of all essential amino acids in the body and 14 to 18% of the essential amino acids found in muscle (2).

Unlike most other amino acids, BCAAs are mainly broken down in the muscles rather than in the liver. For this reason, they play a role in energy production during exercise (12).

But BCAAs play numerous other roles in the body. For example, the body can use them as building blocks for proteins and muscles (13, 14, 15).

They are also involved in regulating blood glucose levels by maintaining glycogen stores in the liver and kidneys and stimulating cells to use sugar from the bloodstream (16, 17, 18, 19).

In addition, BCAAs can help reduce the fatigue felt during exercise by reducing the production of serotonin in the brain (20). Of the three BCAAs, leucine has the greatest impact on the body's capacity to form muscle proteins (13). Isoleucine and valine, on the other hand, appear to be more effective in producing energy and regulating blood glucose levels (16, 21).

Health benefits and benefits for athletic performance:

BCAAs can reduce fatigue during exercise

Consumption of BCAAs may help reduce physical and mental fatigue. Studies in human subjects reported up to 15% less fatigue in subjects receiving BCAAs during exercise compared to subjects receiving only a placebo (4, 5).

In one study, this increased resistance to fatigue helped the BCAA group exercise 17% longer before reaching a state of fatigue compared to the placebo group (6).

In another study, subjects were exposed to heat stress during a cycling test. They were asked to drink either a BCAA drink or a placebo drink. The subjects who drank the BCAA drink were able to last 12% longer than members of the placebo group (7).

However, not all studies have been able to show that reduced fatigue resulted in improvements in physical performance (4, 5, 8, 9, 10). In addition to this, BCAAs may be more effective in reducing exercise fatigue in untrained individuals than in trained individuals (11).

Summary: For some people, BCAAs may help reduce training fatigue. Whether this can improve training performance is still a matter of debate.

BCAA supplements can reduce muscle soreness

BCAAs could also help reduce muscle soreness after exercise. One way they could do this is by reducing blood levels of the enzymes creatine kinase and lactate dehydrogenase, which are involved in muscle damage. This could improve recovery and provide some protection against muscle damage (22).

In different studies, subjects were asked to rate their muscle soreness after performing certain strength training exercises. Subjects who had used BCAA supplements rated their muscle soreness as 33% less than subjects who had received only a placebo (23, 24, 25).

In some cases, those who received BCAAs performed up to 20% better when they retook the same strength training test 24 to 48 hours later (24, 26). However, the effects may vary based on gender and total protein content of the diet (23, 27).

Summary: BCAAs taken before or after strength training could reduce muscle soreness after exercise, although these effects may vary from person to person.

BCAAs could increase muscle mass

Many people who buy BCAA supplements do so to increase their muscle mass. Indeed, scientific research shows that BCAAs activate enzymes responsible for muscle growth (15).

Some studies also show that BCAA supplements may be effective in increasing muscle mass, which is especially true when they contain higher levels of leucine than isoleucine and valine (28, 29).

However, there is no evidence at this time that consuming BCAAs through a supplement is better than consuming them through food or a less expensive whey protein or soy protein supplement. Some studies even show that consuming supplements containing complete protein is better for muscle growth than taking a supplement containing isolated amino acids, at least in some cases (30).

Summary: A sufficiently high intake of BCAAs is likely to increase muscle growth. This intake can be in the form of protein-rich foods or supplements.

BCAAs could lower blood sugar levels

BCAAs may also help maintain normal blood sugar levels. It is believed that leucine and isoleucine can increase insulin secretion and cause muscles to absorb more sugar from the blood, resulting in lower blood glucose levels (16, 31, 32).

In practice, however, not all studies support this (33, 34, 35). Some studies even report a potential increase in blood glucose levels depending on the type of diet followed. For example, if BCAAs are combined with a high-fat diet, then consumption of these amino acids in supplement form may lead to insulin resistance (36, 37). However, many of the studies on the topic have been conducted with animals or isolated cells, which means that their results may not be directly applicable to humans. Even in humans, results may vary from person to person.

In a recent study, for example, subjects were given 12.5 grams of BCAAs three times daily. In 10 subjects, this led to a reduction in blood glucose levels, while no effects were observed in 17 subjects (38). For these reasons, further studies are needed before robust conclusions can be drawn.

Summary: BCAAs may help promote blood glucose control, at least in some cases. However, further studies are needed to confirm these effects.

BCAAs could accelerate weight loss

Branched-chain amino acids could help prevent weight gain and speed up fat loss.

In fact, observational studies report that people who consume an average of 15 grams of BCAAs per day as part of their normal diet have a 30% lower risk of becoming overweight or obese than people who consume an average of 12 grams of BCAAs per day (39, 40).

However, it is worth noting that those who consumed fewer BCAAs also consumed about 20 grams of protein per day less, which may have influenced the results. If one is trying to lose weight, then BCAAs could help the body to better break down unwanted fat.

Competition-level wrestlers who followed a high-protein, low-calorie diet and supplemented with BCAAs lost 1.6 kilograms more weight over 19 days than study participants who received a soy protein supplement instead of BCAAs (41). The BCAA group also lost 0.6% more body fat than the soy protein group, despite consuming the same amount of calories and slightly less protein per day.

In another study, weightlifters who received 14 grams of BCAAs per day lost 1% more body fat over 8 weeks than subjects who instead received 28 grams of whey protein per day. The BCAA group also built 2 kilos more muscle (42). However, these two studies have some limitations. For example, they provide little information about the composition of the supplement and the diet followed, which could have influenced the results.

In addition, studies that have examined the effects of BCAAs on weight loss provide inconsistent results (43).

Summary: BCAAs could prevent weight gain and accelerate weight loss. However, more studies are needed to determine if these supplements provide any benefits beyond those of a high-protein diet.

BCAAs can prevent muscle loss

BCAAs can help prevent muscle breakdown and loss. Muscle proteins are continuously broken down and rebuilt. The ratio of muscle protein breakdown to muscle protein build-up determines the amount of protein in the muscle (44). Loss of muscle mass occurs when protein breakdown exceeds protein synthesis. Muscle breakdown is often a sign of malnutrition and occurs with chronic infections, cancer, periods of fasting, and as a natural part of the aging process (45). In humans, BCAAs account for 35% of the essential amino acids in muscle protein. They also account for 40% of the total amino acids needed by the body (46). For this reason, it is important that BCAAs and other essential amino acids are replaced during periods of muscle breakdown to halt or slow this process.

Several studies support the use of BCAAs to inhibit muscle protein breakdown. This could improve health and quality of life in certain populations such as the elderly or people suffering from diseases such as cancer that lead to muscle breakdown (47, 48, 49).

Summary: Taking BCAA supplements can prevent protein breakdown in certain populations that suffer from muscle loss.

BCAAs could reduce complications of liver disease

BCAAs may help reduce complications associated with liver failure. One possible complication is hepatic encephalopathy (HE), which can lead to confusion, unconsciousness, and coma.

A recent study review suggests that BCAA supplements may be more useful than other supplements in reducing the severity of HE in patients with liver disease (41). However, BCAAs did not improve overall survival or reduce the risk of other complications such as infection and gastric bleeding.

Another study review involving subjects who had undergone liver surgery reported that BCAA-enriched solutions could help improve liver function, reduce the risk of complications, and reduce the length of hospital stay (42).

BCAA supplements may also be effective in reducing fatigue, relieving weakness, improving sleep quality, and reducing muscle cramps in people with liver disease (43).

In the case of liver cancer, taking BCAA supplements could help reduce water retention and lower the risk of premature death by up to 7% (44).

Summary: BCAA supplements could be effective in improving liver function and reducing complications in people with liver disease.

BCAAs could alleviate sleep disorders

In a clinical trial of 5 healthy men, nocturnal BCAA infusions improved respiratory control and could potentially help reduce sleep apnea (54).

In a study of 7 patients with renal failure, evening intake of a BCAA supplement increased the time of REM sleep and reduced end-expiratory CO2 levels, which are important for dreaming and respiratory function during sleep (55).

Typical groups for an additional demand of isoleucine, leucine and valine

The need for the branched-chain amino acids isoleucine, leucine and valine is particularly increased during physical stress and intensive sports training. The daily intake from the diet may then not be sufficient to cover the necessary requirement.

• People with high physical stress
• Athletes with intensive training
• In diseases associated with low levels of branched-chain amino acids.

When isoleucine, leucine and valine are missing in the body

During strong physical stress, possibly also during high athletic performance, the need for the branched-chain amino acids isoleucine, leucine and valine can increase. They are then broken down more quickly, with protein reserves in the muscles also being dissolved. Leucine, in particular, can oxidize during very intense training and thus drops out for protein synthesis. These amino acids can be reduced in disturbed functions of the nerve muscles and must then be supplemented. In schizophrenia, they lower the blood levels of the amino acids phenylalanine and tyrosine, which are needed for the formation of the neurotransmitter dopamine.

Maple syrup disease is a very rarely occurring metabolic disease in which the breakdown of isoleucine, leucine and valine is disturbed. This disease is therefore also called valine-leucine-isoleucinuria. Typical is the smell of the urine like caramel or maple syrup. It is caused by the decomposition of the amino acids isoleucine, leucine and valine, which are present in increased amounts in the blood. This disease manifests itself already in infancy and leads to brain damage. Therapy involves a lifelong diet in which the intake of isoleucine, leucine and valine is reduced.

Sports use

In order to stay in optimal shape, athletes who train regularly in particular are forced to provide themselves with sufficient protein on a daily basis. Since variation is the key to a balanced, high-quality diet, on the one hand they face the problem of also having to choose protein sources that contain a relatively high amount of fat, and on the other hand they must always achieve a protein surplus (even if not excessive) in order to balance amino acid balances and digestive losses.

Branched chain amino acids (BCAAs), so called because of their specific molecular structure, may be the solution. They offer the following advantages to the athlete:

• They are extremely important for the regeneration and maintenance of muscle tissue,
• have a strong anabolic (anabolic) effect,
• positively influence the energy balance
• improve endurance, and
• act as nitro donors (nitrogen suppliers) for the build-up of non-essential amino acids (alanine/glucose cycle).

When you eat a protein-rich meal, the branched-chain amino acids are the first to be absorbed. After being reworked in the liver, almost 70% of all amino acids entering the blood are BCAAs. After that, they are absorbed very quickly by the muscles. In the first three hours after a meal, branched-chain amino acids account for about 50-90% of the total amino acid uptake by muscles. In addition, BCAAs, especially leucine, stimulate the production of insulin. Insulin, together with BCAAs, supports the uptake of all other aminos (except tryptophan) by muscle cells. To get the most out of the branched-chain amino acids, they must all be taken together (taking leucine alone has a negative effect on protein utilization in the body). The rapid absorption of BCAAs prevents the absorption of two other important amino acids of the same group, tryptophan and tyrosine. As single, free amino acids, they should not be taken together with BCAA preparations, but preferably at a time interval of three hours.

Three substances are particularly important for the metabolism of BCAAs: biotin, pantothenic acid and vitamin B 6. If you take a preparation with branched-chain amino acids, you should make sure that you have a sufficient supply of these nutrients.

The isolated supply of BCAAs, i.e. the sole intake of all three branched-chain amino acids before strength or endurance training, can no longer be justified according to recent findings. The intake before the workout results in a considerable urea load during the energy production from BCAAs. From 1g BCAAs, approx. 0.5g urea is produced, which puts a strain on the organism. For this reason, it is not advisable to take BCAAs before endurance training in particular, but even forced strength training is likely to cause the body to use previously taken isoleucine or valine mainly for energy production.

The isolated supply of leucine, isoleucine and valine can temporarily disrupt protein synthesis for muscle building. BCAA preparations should therefore be taken better in conjunction with other protein, preferably with proteins that have only small amounts of branched-chain amino acids.

One advantage of the supply of BCAAs for the athlete is the ammonia-lowering effect that these amino acids exert on the organism. While arginine and ornithine support the liver in breaking down the metabolic "slowdown agent" ammonia, leucine and isoleucine can perform the same task in the muscles. Since BCAAs are preferentially transported in the blood, they inhibit the delivery of other amino acids of the same group, such as tryptophan, phenylalanine and tyrosine to the brain. Therefore, if you value a high serotonin output (and thus a higher HGH output), you should not take BCAAs in addition to dietary protein if possible. The branched-chain amino acid L-leucine is of particular importance in energy metabolism. Especially in times of reduced carbohydrate intake (slimming diets, competition preparation), leucine can mitigate the effects of reduced energy intake from glucose from carbohydrates - (blood) plasma glucose to maintain blood glucose levels - by inhibiting the breakdown of glucose in muscles and brain. Valine and isoleucine are mainly used for gluconeogenesis (new formation of glucose) in carbohydrate deficiency. But the effect of leucine as a regulator in glucose deficiency should not be overestimated and does not alone justify increased leucine intake.

More important in this context is the disproportionately high breakdown of leucine in the muscles during physical exertion compared to other amino acids. The loss of leucine is quickly compensated by the body's own reserves (amino acid pool, muscle protein). This circumstance would justify a disproportionate intake of leucine in athletes. However, it is not advisable to take leucine in isolation. Better is the intake of high-quality protein, which has a high content of leucine, or the combination of BCAAs with other protein.

Dosage

The amount of BCAAs you should supplement depends on your individual needs and goals.

A 1985 World Health Organization (WHO) report states that the average adult should consume a minimum of 34 mg of BCAAs per kilogram of body weight per day (1).

However, more recent studies suggest that the daily requirement may be as high as 155 mg per kilogram of body weight per day (2, 3).

Based on recent studies, adults should aim for the following amounts of BCAAs per day:

• Women: At least 9 grams of BCAAs per day.
• Men: At least 12 grams of BCAAs per day.

People who consume adequate amounts of protein-rich foods usually do not need additional BCAA supplements. However, the daily requirement might be higher for athletes and people who train with weights. In these cases, supplementation may be beneficial.

Most studies that observed benefits in trained subjects used supplementation in the range of 10 to 20 grams of BCAAs per day. The best time to take BCAA supplements is before and/or after a workout. Many people trying to build muscle also take BCAAs in the morning and before bed. However, whether the exact time of ingestion makes a big difference has not been adequately studied.

Is it possible to overdose on isoleucine, leucine and valine or are there side effects?

Side effects of supplemental intake of isoleucine, leucine and valine are practically unknown. At high intakes, they are converted into other amino acids, used as energy or converted into storage fat. However, people with liver and kidney diseases should not take these amino acids without therapeutic recommendation.

High doses of these amino acids can also hinder the transport of the amino acid tryptophan, a precursor of serotonin, into the brain.

Precautions and warnings

Pregnancy and lactation: Not enough is known about the safety of BCAAs during pregnancy and lactation. For this reason, pregnant and lactating women should avoid BCAAs to be on the safe side.

Amyotrophic Lateral Sclerosis (ALS): The use of branched chain amino acids has been associated with lung failure and higher death rates when used by ALS patients. For this reason, if you suffer from ALS, you should not use BCAAs until more is known.

Ketoaciduria: In people suffering from ketoaciduria (maple syrup disease), an increase in the intake of branched-chain amino acids can cause seizures and serious physical and mental disorders. For this reason, BCAAs should be avoided if you suffer from this disease.

Chronic alcoholism: Use of branched-chain amino acids by alcoholics has been associated with liver damage leading to brain damage (hepatic encephalopathy). Low blood glucose levels in young children: There are reports that taking the branched-chain amino acid leucine can lower blood sugar in young children suffering from idiopathic hypoglycemia. However, the cause of this is unknown. Some scientists suspect that leucine stimulates the pancreas to secrete insulin, which lowers blood glucose levels.

Surgeries: Ackerkraut could affect blood sugar levels and therefore there are concerns that BCAAs could affect blood sugar control during and after surgery. For this reason, one should stop taking BCAAs two weeks before upcoming surgeries.

Interactions

Caution should be exercised when combining BCAAs with the following medications

Levodopa

Branched-chain amino acids could reduce the amount of levodopa the body absorbs. By reducing the amount of levodopa the body absorbs, BCAAs could decrease the effectiveness of levodopa. For this reason, branched-chain amino acids and levodopa should not be taken at the same time.

Diabetes medications

BCAAs could lower blood sugar. Diabetes medications are also used to lower blood sugar levels. Taking branched-chain amino acids in combination with diabetes medications could result in an excessive drop in blood glucose levels. For this reason, blood glucose levels should be carefully monitored. It is possible that the dosage of diabetes medication may need to be adjusted.

One should be vigilant when combining BCAAs with the following drugs

Diazoxide

Branched-chain amino acids are used by the body to make proteins. Taking diazoxide in combination with BCAAs could reduce the use of branched-chain amino acids for the purpose of protein production. However, more information is needed on this interaction.

Medication against inflammation (corticosteroids)

Branched-chain amino acids are used by the body to produce proteins. Taking glucocorticoids in combination with BCAAs could reduce the use of branched-chain amino acids for the purpose of protein production. However, more information is needed on this interaction.

Thyroid hormones

Branched-chain amino acids are used by the body to make proteins. Some thyroid hormones can slow the breakdown of BCAAs by the body. However, more information is needed to make a statement about the significance of this interaction.

Conclusion

BCAA supplements can bring impressive benefits in certain circumstances, which is especially true when it comes to muscle growth and physical performance. However, BCAAs are also found in many protein supplements and a variety of protein-rich foods. For this reason, a BCAA supplement may not be absolutely necessary, which is especially true if adequate amounts of BCAAs are supplied via protein supplements and/or the normal diet.

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