I put on about 50lbs in 3 years by eating nonstop(the right foods) and heavy lifting. I quit doing high reps/low weights and started lifting heavy and low and behold things that would never grow(like my chest and lats) started putting on size. Pretty soon my 8 reps on those heavy weights turned to 10, turned to 12, and then I had to increase the weight once again. Working so far!