" It hasn't been scientificly proven that localized growth however in theory it should work for three reasons:
1) It has been proven that the stretch of the fascia in the muscle creates additional space for new muscle to be developed. This is why muscle memory exists , and it is always harder to gain muscle size you have never had compared to gaining muscle size you have had before. The stretch of the fascia takes time and requires hard training to encourage where as if the fascia is already stretched the time required to add muscle in that space is much less.
Based on this the belief is localized injections will cause a stretch of the fascia... which explains why synthol works.
2) Fast acting AS such as prop and winstrol are believed to be acting immediately in the muscle of which it was injected. Because of this behavior the muscle of which you inject in should have an additional benifit of this fast acting steroid.
3) Everyone who has injected locally has confirmed tremendous muscle pumps. It has been proven that the bigger the pump the more blood ( carrying nutrients ) will fill the muscle. Therefore , the belief is that more blood in the muscle leads to faster recovery and eventually more growth. Hence , the bigger pumps help increase the amount of growth for the injected muscle.
Based on this I would say localized growth does exist. "
source :
http://www.elitefitness.com/forum/archive/index.php/t-93768.html
Like I said , it is a myth and there is no scientific proof . So you can choose to believe it or not .
Victor
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