Assuming a normal intact endocrine system.
The key regulators of skeletal muscle protein synthesis are mechanical loading, availability of essential amino acids and proper recovery. This has been clearly demonstrated in the literature and I think we all know this by now with plenty of anecdotal experience.
With regard to supplements beyond a solid diet, I haven't seen any sound science that consistently supports enhanced skeletal muscle protein synthesis that results in performance enhancement (i.e., increased strength) from any OTC non-hormonal product, the only exception being some of the newer prohormones (1-AD) that may in a few guys have some anabolic effects, but we're still back to AAS, just legal ones with more sides than some of the illegal ones.
While there are some that truely believe that glutamine, BCAAs and other OTC products really help, the studies done to date really don't support those contentions. I as well as a number of my colleagues have been down that road (BCAAs, glutamine, HMB and just about everything else) with no added muscle building effects beyond a solid training program and good diet with plenty of protein and energy.
The only exception being creatine, but it doesn't directly enhance muscle protein synthesis, however in the long run, may increase lean mass because of its positive effects on cell volumizing and enhancing mechanical loading.
I do believe in anti-oxidants (NAC, grape seed, Vit C and E, r-ALA, lycopene, cruciferous veg extract and lutein), not for performance enhancement, but long-term chronic disease prevention (heart disease, stroke, cancer, immune dysfunction and other disease of inflammation). Same with essential fats (omega-3 (EPA and DHA) and omega-6 (GLA)).
Aside from AAS, nothing else really compares (i.e., GH, IGF-I, clenbuterol, insulin, etc.).
mg for mg, nothing promotes protein synthesis better than anabolic-androgenic steroids, assuming all else is optimized and you've pretty much hit your genetic limits which vary widely from person to person.
Believe me, I've been searching for years, reading the literature, listening to other lifters and their experiences and all the hype from supplement company reps.
W6
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Gives muscles a little roundness, gives you a nice pump (so your workouts are great) and also holds a little extra water, so the scale shows a little more weight (makes us, guys, happier). So.. it is great for when your are off, I am planning to get some for myself and my gf, but I doubt it would add any muscle.
