i've been natural since day 1 of lifting. and i've packed half an inch onto my arms in about 2 1/2 weeks. this is totally natural not even taking creatine. this is the first time i've ever had it happen to me like this its really odd. and what i find twice as odd about it is my chest being trained in the same way as my arms hasn't grown any. what could've cause this? keep in mind it is naturally.well ok i can't say my chest hasn't grown any there is a visible difference in my pecs. but it doesn't measure any bigger. is this odd or what?
How long had you been training when this happened? Could be because you'd taken a break and trained with more intensity when you got back, could have measured it slightly differently, eg time of day, location, slightly pumped, not at all pumped. If this 1/2 inch is still there a couple of days later rejoice.
Absolutely no reason to worry about the pecs, if there is a pronounced imbalance worry about it then. Like Bluto said, you may also have a body part that responds well.
