Steroid isolation , depending on context, is the isolation of chemical matter required for chemical structure elucidation, derivitzation or degradation chemistry, biological testing, and other research needs (generally milligrams to grams, but often more  or the isolation of "analytical quantities" of the substance of interest (where the focus is on identifying and quantifying the substance (for example, in biological tissue or fluid). The amount isolated depends on the analytical method, but is generally less than one microgram.  [ page needed ] The methods of isolation to achieve the two scales of product are distinct, but include extraction , precipitation, adsorption , chromatography , and crystallization . In both cases, the isolated substance is purified to chemical homogeneity; combined separation and analytical methods, such as LC-MS , are chosen to be "orthogonal"—achieving their separations based on distinct modes of interaction between substance and isolating matrix—to detect a single species in the pure sample. Structure determination refers to the methods to determine the chemical structure of an isolated pure steroid, using an evolving array of chemical and physical methods which have included NMR and small-molecule crystallography .  : 10–19 Methods of analysis overlap both of the above areas, emphasizing analytical methods to determining if a steroid is present in a mixture and determining its quantity. 
I get 2, 4 and 5 and I’m completely natural. I have had people accuse me of taking steroids many times and it pissed me off. It gets me to the point where I want to take steroids just so that I can say “Now this is me on steroids fckers!”. Lol. But nah I get a lot of acne outbreaks naturally and I have had many stretch marks as well as abnormally fast muscle gains. I’m a very lean person and when I stop working out I’m capable of drastically going from jacked to skinny as heck. When I start back up again I blow up quick. Another thing I’ve noticed is my pumps are naturally a lot more intense then the average lifter. Like my shoulders blow up like bowling balls and veins and shreds show up all over them along with my arm’s and chest. I’ve had a tone of people accuse me of taking steroids because of these factors. I also had a relative hug me once and say I was jacked and as solid as steal. He said only steroids do that. (He took steroids in the past) But it is to my understanding that muscle is solid… or at least a lot more solid than fat. At the time I was taking creatine and l-arginine with citrilline malate (which is a precursor to arginine) and a lot of BCAA’s.