What is the maxmium rate, in pounds, of muscle growth for someone lifting weights who is not on steroids? And how long does it take on average to gain each pound of muscle?
There are too many variables for a pat answer. Here is an article that covers most of the bases:
Um, even the author of that article is a bit liberal with his numbers.
Look for more like 8-12 pounds of lean muscle mass a year.
Of course it varies from person to person, 15 pounds would be pushin’ it.