12 pounds of muscle in a year? Bowflex commercial

There is this commercial showing some guy that plays in a Rock Band as a hobby and claims he added 12 pounds of muscle in a year. That can't be possible can it? I thought full time Gym rats/ amature bodybuilders might add 5 pounds a year but Twelve?

5 lbs a year even sounds like a lot. I had always heard 1/2 to 1 lb of lean muscle tissue per year. Not sure if that includes previously lost muscle tissue or if that is only completely new muscle tissue.

Haven't been able to find a figure for that anywhere.

Dave

I just put a Bowflex on the curb hoping some one haul it off.

Don't get me wrong, I am not considering buying a bowflex, I just thought the commercial claim was a bit much.

I just want to look like the bowflex guy...

I don't know, I'm sure there are studies on this but I don't know about them.  I actually don't find 12 hard to believe.  In college I got to 19% body fat at ~220 pounds in two years from 285 and not working out at all.  I think I must have exceeded 5 pounds a year, though I haven't done the math (and don't know my starting LBM).  It's going to depend on genetics, routine, nutrition, how much extra fat you're willing to have on your body (more room to grow), how big you are (surely a 6'5" guy can add more than a 5'6" guy).  Age is going to be very important; I'm sure I can't put muscle on as fast as when I was 18, and guys over 40 have to overcome an uphill climb.  Also, beginners are going to be able to add a lot more than people 10 or even 2 years out.  We are all approaching a genetic limit in total muscle mass the shape of a logarithmic equation (for the math geeks, oh, I'm the only one? sorry.).  The further down you are on the graph, the more you can gain in time X. So is 12 pounds possible?  I think very much so (though probably not typical).  That said, I wouldn't buy a bowflex.