Correction: I didn’t mean “the recommended amount of protein”. I meant a little bit more than that (in order for the excess to be stored for 24h like you said), so… if in the middle of my sleep my muscles were to begin “digesting themselves”, those extra amino acids that were supposedly stored for backup would do their job. Right? In that case… Casein only makes sense if you think that the amount of protein intake during the day was not enough to garantee that some of it was stocked for later use.
The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine . 
I am 29 years old weighing 5'6"i use to be lowest i got to was way i got that weight was alot of jumping jacks,push ups,and sit with only having a whey protein shake after working durinig work at a nine hour shift i would eat salad with low fat cottage work i would pound down as much food as i thats all fine and well for losing weight now that i have all the weights and everything i need to gain muscle what is the best way to gain that muscle and not SINCE I HAVE A HISTORY OF HAVING A SLOW AND FAT GAINING METABOLISIM:^)