What are BCAAs?
BCAAs are essential amino acids that bodybuilders use. BCAAs help many athletes increase power output, reduce fatigue, and improve fat loss. There are 20 different amino acids that make up the thousands of different proteins in the human body.
Nine of the 20 are considered essential amino acids, meaning they cannot be made by your body and must be obtained through your diet. Of the nine essential amino acids, three are the branched-chain amino acids (BCAAs): leucine, isoleucine and valine.
“Branched-chain” refers to the chemical structure of BCAAs, which are found in protein-rich foods such as eggs, meat and dairy products. They are also a popular dietary supplement. BCAAs are the largest collection of amino acids in the body, accounting for up to 35% of muscle proteins. Normally, BCAAs are excreted rapidly. BCAA intermediates can be toxic at high concentrations, so functional BCAA breakdown is vital. BCAA formulas have been on the market since 1996, mainly for treating liver diseases. Nowadays, BCAAs are mainly used by bodybuilders for exercise purposes, to increase energy, and to boost protein synthesis.
Here are 6 proven benefits of BCAAs:
1) BCAA Supplementation Improves Exercise Performance. Increase Muscle Growth.
Exercise leads to amino acid usage. BCAAs become rapidly depleted after exercise, showcasing the possible beneficial effects of BCAA supplementation. In a double-blind randomized controlled trial (DB-RCT) of 218 marathon runners, BCAA supplementation improved mental and physical performance. The running times of slower athletes improved. In a study (DB-RCT) of 12 volunteers, BCAA supplements increased power output. In another DB-RCT of 36 males, BCAA supplementation increased their muscle strength more compared to other supplements, like whey protein and carbohydrate supplements. This effect could be caused by increases in cortisol as seen in a DB-RCT of 10 volunteers. Cortisol controls the fight-or-flight response, which can flood muscles with glucose, providing great amounts of energy. A study showed that a 3.57% BCAA-supplemented diet increased swimming time until exhaustion by 37%.
BCAA Supplementation Reduces Fatigue and Increase Endurance
In a study (DB-RCT) of 218 marathon runners, BCAA supplementation reduced fatigue after a race. In another DB-RCT of 7 volunteers, their fatigue decreased by an average of 17.2%. Similarly, BCAA supplementation can increase endurance. In a DB-RCT of 10 endurance runners, the runners given BCAA supplements ran better times for two consecutive days in a row in both 5,000 and 10,000 m races. BCAA supplements also increase lactate threshold (LT) in a study (DB-RCT) of 8 volunteers. LT measures endurance capacity as any exercise below the LT means lactate does not build up in the muscles. Oxygen consumption (VO2) is a measure of LT and the study showed that overall VO2 measures increased by 13% and max VO2 increased by 4.2%.
BCAA Supplementation May Improve Fat Loss
In a DB-RCT of 7 volunteers, BCAA supplementation increased fat loss which is associated with improvements in aerobic exercise.
BCAA Supplementation Increases Lean Mass
In a DB-RCT of 36 body-builders, BCAA supplements increased lean mass by an average of 4 kg, which was more than other bodybuilding supplements like carbohydrate supplements and whey protein.
BCAA Supplementation May Reduce Soreness
In a DB-RCT of 12 healthy female volunteers, BCAA supplements decreased delayed-onset muscle soreness (DOMS) by 80%. Soreness reduces exercise performance in subsequent days.
BCAA Supplementation May Reduce Muscle Damage
Supplementing with BCAAs decreases protein degradation in the muscles. Additional studies have shown that supplementation with a metabolite of leucine (HMB) led to lower levels of enzymes that indicate muscle damage.
BCAA Supplementation May Increase Short-Term Memory Performance After Exercise
A DB-RCT of 12 volunteers showed that after exercise athletes without BCAA supplementation had reduced short-term memory. Memory performance in BCAA supplemented volunteers did not decrease.
BCAA Supplementation May Increase Reaction Times
In a DB-RCT of 10 soccer players, those given BCAA supplements showed an increase of up to 10% in reaction time.
BCAA Supplementation May Reduce Perceived Exertion
In a DB-RCT of 7 cyclists, BCAA supplementation reduced the exertion that was perceived by the athletes by up to 7%.
BCAA Supplementation Reduces Perceived Pain
Norepinephrine is released in the brain to manage pain. BCAA supplementation increased norepinephrine, thereby, reducing pain.
BCAA Supplementation Improves Breathing
BCAA supplementation decreased blood CO2 levels by 9%, which normally increases with exercise. It also increased average oxygen intake (by 19%) and minute ventilation (by 22%), which measures the volume of gas inhaled by the lungs per minute. Finally, BCAA supplementation increases ventilatory response, which allows the body to process and receive oxygen at higher rates.
BCAA Supplementation Does Not Affect Heart Rate
Although some BCAA users mention it as a typical concern before starting supplementation, scientific evidence shows that BCAAs don’t affect heart rate by themselves. In a study of 12 men taking BCAA supplements did not increase heart rate. Other studies showed that heart rate did not change, or that it even decreased. The increased heart rate seen by some users may be due to other components in the supplements such as caffeine.
2) BCAA Supplementation May Improve Liver Health
In one DB-RCT, BCAA supplementation not only increased nutritional status but also improved sleep and decreased fatigue in liver cirrhosis patients. Furthermore, in a DB-RCT of 16 controls, 20 chronic hepatitis patients, and 100 cirrhosis patients, BCAA supplementation greatly increased albumin in the blood, which leads to declines in both liver diseases. Liver survival rate without any detrimental event was around 63.6% with BCAA supplementation.
3) BCAA Supplementation Can Help the Kidneys
BCAA supplementation reduces the chances of kidney failure by up to 40%. It increases amino acid levels but not protein intake, which decreases kidney damage. BCAA supplementation also improved appetite and nutrition in dialysis patients.
4) BCAA Supplementation May Prevent Heart Failure
In studies, BCAA supplementation improved outcomes after induced heart failure and cardiac cachexia (severe weight loss), improving functions such as:
- Decreased heart rate
- Increased heart function
- Increased survival time
- Decreased weight loss
- Increased mitochondrial function
- BCAA breakdown deficiencies are linked to increased heart disease risk
5) BCAAs May Increase Energy
During states of increased amino acid levels, the amino acids will compete with glucose to provide energy, thereby becoming a secondary source of energy. In one study, people with high levels of amino acids required 36% less glucose. Isoleucine (a BCAA) decreased glucose usage by 20% in the blood and 71% in the muscles. Isoleucine and valine can also be converted to glucose for energy. One gram of BCAA is around 4 calories.
6) BCAA Supplementation May Improve Sleep
Some patients with kidney problems develop sleep disorders such as sleep apnea, which can reduce sleep quality and time. In a study of 7 patients, taking BCAA supplements at night increased rapid eye movement (REM) sleep and decreased end-tidal CO2 levels, which are important for dreaming and respiratory function during sleep.