Pubmed is the easiest and most convienient database of research articles on the web. It combines all forms of studies, meta-analysis, cochrane reviews, RCTS, cohort, case reports, in vivo and in vitro studies. If there is something you would like to know about supplementation, physiology, medicine etc.. pubmed is your spot. Pubmed has a google like search strategy unlike medline so its extremely user friendly, however there are search strategies which will get you to where you want to go quicker.
http://www.nlm.nih.gov/bsd/disted/pubmedtutorial/010_040.htmlThis tutorial will show you everything you need to know about pubmed in order to navigate it. However, i will simplify it further. So anything can be typed into the search function, similar to google and it will give you relevant results barring spelling mistakes. I will use the example in the tutorial, but because of the Mesh feature pubmed searches like terms in case your search query is ineffective. For example
Renal transplant is a synonym for the MeSH term, Kidney Transplantation.
one way to get very specific is to search for particular quotes with greater precision using Boolean connectors, most likely you will be using AND, OR.
they have to be capitalized and to search for terms in a paper in quotations. Ill do some examples.
say you want to do a search for arginine on GH
or as an ergogenic aid in general
so your search would be "arginine supplemenation AND growth hormone OR ergogenic aid" what this does is specifys that you want to know about arginine and growth hormone or arginine as an ergogenic aid, it will search for both.
if your search is more specific in that you wanted a study with both effects it would be
"arginine supplementation AND growth hormone AND ergogenic aid"
another example
"arginine OR leucine AND protein synthesis"
you can search them without quotes to have a broader search. Complete the tutorial above and you should be able to navigate pubmed very easily and learn and research about anything you want related to bodybuilding. Any questions fire away. There are more advance searches and boolean connectors but i think they are unnescessary for this brief intro.