Substance use disorder occurs when a person needs alcohol or another substance (drug) to function normally. Abruptly stopping the substance leads to withdrawal symptoms. Addiction means that a person has a strong urge to use the substance and cannot stop, even if they want to.
So it is important to maintain positive nitrogen balance in the body while sleeping. When you do and conditions are right so that your rate of protein synthesis exceeds your rate of degradation, and you maintain a positive nitrogen balance, you can grow while you sleep.
According to this theory activities during the day deplete key factors in our brain or our body that are replenished and repaired by sleep. This theory makes sense since during stage 4 sleep there is a marked secretion of growth hormone, controlling many aspects of metabolism, physical growth, and brain development.