*sigh* --
There is no "upper chest"!!! The chest grows as a whole!!! You cannot target one part of your chest at the exclusion of another....you CAN however, train the different pressing angles (flat, decline, incline) for a different stimulus to the
chest muscles, which may produce more overall growth for the entire muscle, but you cannot specifically target one portion over another.
I used to believe that you could as well, but the evidence overwhelmingly is in agreement that you cannot target a specific part of the chest....
My
advice based on what I am finding right now, is that if you are not into powerlifting, skip the
flat bench press and concentrate on declines, inclines, and dips. I see no need for the flat bench unless you are training for bench press glory--the decline press (on a slight decline mind you, around 15-20 degrees) I find will work the entire chest muscle much more throroughly than flat press, and will be less stressful on your shoulders. IMO, it is the one pressing movement where you can completely concentrate on your chest muscles without too much help or involvement from the shoulders or tris....