just to add some personal experience in here. I used to blast my arms with isolations when i was younger. Even through college my arms didnt grow much, went from 16.25" to around 17" or so in 4 years.

It wasnt until I dropped most of the isolations that they got bigger. They are now slightly over 18".

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I don't do this for my family, my friends, women, accolades, pride, or ego. I do it for me and no one else, its just part of who I am.