Different types of AAS bind to the AAR with different affinities, depending on their chemical structure.The effect of AAS on muscle mass is caused in at least two ways: first, they increase the production of proteins; second, they reduce recovery time by blocking the effects of stress hormone cortisol on muscle tissue, so that catabolism of muscle is greatly reduced. It has been hypothesized that this reduction in muscle breakdown may occur through AAS inhibiting the action of other steroid hormones called glucocorticoids that promote the breakdown of muscles. AAS also affect the number of cells that develop into fat-storage cells, by favouring cellular differentiation into muscle cells instead. Anabolic and androgenic effects
As their name suggests, AAS have two different, but overlapping, types of effects: anabolic, meaning that they promote anabolism (cell growth), and androgenic (or virilizing), meaning that they affect the development and maintenance of masculine characteristics. Some examples of the anabolic effects of these hormones are increased protein synthesis from amino acids, increased appetite, increased bone remodeling and growth, and stimulation of bone marrow, which increases the production of red blood cells. Through a number of mechanisms AAS stimulate the formation of muscle cells and hence cause an increase in the size of skeletal muscles, leading to increased strength.The androgenic effects of AAS are numerous. Depending on the length of use, the side effects of the steroid can be irreversible. Processes affected include pubertal growth, sebaceous gland oil production, and sexuality (especially in fetal development).
Children and Teenagers
It is not recommended for children under the age of 18 to consume several caffeinated drinks according to the American Academy of Pediatrics (AAP). If they were to consume caffeine it is recommended to follow some guidelines so they do not consume too much throughout the day. If they do, they can become dependent on caffeine and without it can suffer many different side effects. These include increase of heart rate and blood pressure, sleep disturbance, mood swings, and acidic problems. Long lasting problems on childrens nervous system and cardiovascular system are currently unknown and studies are still being conducted on it. Tolerance
Tolerance levels regarding caffeine typically vary from person to person. Caffeine tolerance occurs when the stimulatory effects of caffeine decrease over time due to regular consumption. According to H.P. Ammon from the National Library of Medicine, caffeine tolerance occurs when the body responds to an intake of caffeine through the up-regulation of adenosine-receptors. References


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