Man boobs dont go away with exercise, if they are mostly glandular mass. If you have had man boobs most of your life it is most likely glandular, and will require surgery. I know because I live that nightmare, since 2nd fking grade, had surgery at 14, decent results, but gained alot of weight, now my boobs are back, but shaped differently and are mostly fat, which can be lost, but surgery will still be required. If you are as unfortunate as I am, surgery is your only hope, and even with surgery you may never have a normally flat chest.
Oh yeah, life is a bitch