What is cortisol?
Cortisol is the main catabolic hormone. Increasing its level leads to the destruction of muscles to amino acids that can be absorbed by the body, and glycogen (the main nutrient for muscles) to glucose, again for quick energy.
It is important that an increased level of cortisol leads to activation of the processes of accumulation of subcutaneous fat, enhances appetite (due to an increase in blood glucose), and also causes an increase in blood pressure.
Training and Cortisol Levels
Cortisol is produced in response to stress, fatigue, physical exertion, starvation, fear, and other emergency situations. For comparison: the normal level of cortisol is 10 g / dl, with a cold - 40 g / dl, with stress - 80 g / dl, with severe shock - 180 g / dl.
If we talk about physical activity, then in the first minutes of training, the natural level of cortisol rises to 63 g / dl, then it drops to 35 g / dl by about 45 minutes, and again begins to increase sharply (see graph *, top line).
How to lower cortisol levels?
It was found out that if during the training itself you use 5-10 g of BCAAs (the three most important amino acids for us) mixed with 20-30 g of simple carbohydrates (calculation for a person weighing 75 kg), then the level of cortisol is significantly reduced (see graph, bottom line).
This is easily explained by the fact that the hormone cortisol is produced for emergency supply of energy to the body, and if a person receives important amino acids and glucose anyway, then his body just does not need to make excessive sacrifices.
Optimal training duration
As can be seen from the graph, after 45 minutes of training (without additives in the form of BCAAs and glucose), the level of cortisol rises sharply - this means that after this time the body begins to eat its own muscles for energy.
Actually, it is from here that the recommendation comes in for no more than 45-60 minutes. But the good news is that when you take supplements, you lower the level of cortisol, and training can be longer and more effective.
Why does BCAA help?
BCAAs are the three most important amino acids that cannot be synthesized in the body on their own (leucine, isoleucine, valine). Moreover, leucine is critical for muscle growth, and with its lack of muscle just does not grow.
By taking BCAAs in the first half of your workout, you provide muscle with a significant supply of leucine. And the above 20-30 grams of simple carbohydrates (you can use regular sugar) are important for the body to quickly synthesize energy.
During training, the stress hormone cortisol is produced, which destroys muscles. Maximum production occurs at 45-60 minutes after the start of the workout. The use of additives can stop this process.
Scientific sources: Fahey TD, Pearl M. The hormonal and perceptive effects of phosphatidylserine administration during two weeks of resistanve exercise-induced overtraining.
Biol Sport, 1998 15: 135-144. The study involved 10 men aged 26 ± 1.5 years, weighing 89.3 ± 4.7 kg and a height of 176.8 ± 2.7 cm.