During physical exertion, your muscles produce lactic acid. This acid lowers the blood pH to an abnormally low level. This acidification process releases the blood tryptophan from the proteins that normally trap this amino acid. The level of free tryptophan increases, which facilitates its journey into the brain. Tryptophan then invades the neurons and transforms into serotonin, a neurotransmitter that causes fatigue. Performance levels collapse. Some people start to feel sleepy, while others develop headaches.
There is a way to block these adverse effects of tryptophan and serotonin: valine acts in synergy with leucine (2). Their intake, through a kind of competition, prevents the transformation of tryptophan into serotonin, which delays the arrival of fatigue. For trained athletes, taking BCAAs 30 minutes before exertion immediately boosts performance by 6% compared to those taking a placebo. This improved resistance is due to a 12% increase in VO2 max (3). Abnormally low levels of valine are found in athletes suffering as a result of over-training and chronic fatigue (4).
BCAAs during training sessions
During weight training, blood BCAA levels decrease by 20%. Without supplementation, this level remains low, right at the time that it is important to boost BCAA concentrations. Ninety minutes after training, this decrease still hits 16%. Leucine is the most affected of the three BCAAs, with a 21% drop (5).
Unlike other amino acids, the level of valine in the muscles increases sharply (+ 35%). This explains the drop in valine in the blood, which is where this amino acid has its anti-fatigue effect. This counter-productive performance crossover highlights the importance of BCAA 2.1.2 Nutrimuscle Resistance before and during exercise.
BCAAs and dieting
If your low-calorie diet causes severe fatigue, Nutrimuscle BCAA 2.1.2 Resistance will help you regain energy while fighting catabolism. BCAAs increase the level of hormones that stimulate fat loss (growth hormones) and decrease your appetite (GLP-1). At the same time, they inhibit the activity of the enzymes responsible for adipose development (1).
For example, for 19 days, athletes followed 1800-calorie diets containing varying levels of BCAAs (1).
With an unsupplemented diet, they lost 1.9 kg. With the same diet supplemented with BCAAs, they eliminated 4 kg. Fat loss was 50% greater around the stomach area and waist, and muscle wasting was reduced by 30%. Thanks to BCAAs, the body draws more calories from adipose tissue and less from muscle.