wolverine, it's been my experience that you don't want to try to increase one muscle group only. like you said you wanted to keep your chest its same size. by working out to try and keep your chest its same size and increase your arms, you're confusing your body, which will do what it naturally does, which for you, i think, is to stay small. i think if i remember your picture, you're a type of ectomorph. what you want to do is when you're trying to increase one muscle group, you're going to need to increase them all. now here's a secret.

what you should do is stick with the weight gainer shakes/complex carbs, protein, and lots of hard work. with that, you should work to increase all muscle groups, but hit your arms the hardest. try the 5x5 routine. i never did it, but i was always slightly endomorphic, so i didn't need to. work your chest with slightly less intense regimes, and the same with your back, traps, legs, etc. here's another tip-don't devote one day to "arms" just like that. what i do is 'back and bi's', then 'chest and tris', then another day is 'shoulders, traps, and forearms' like that. this way, the lion's share of muscle-building nutrients goes to the section of 'arm' you did that day, provided you work those arms harder than the rest. try that out, and see the results!!
