You exhibit the classic
posture problem many other people have.
You may be
surprised that your problem of not being able to work your chest properly while
performing push-ups is most likely your posture.
If the muscles in your upper middle back are weak, your shoulders wont be
able to properly stabilize in retraction.
This means when you perform push-ups you will be primarily using your
anterior deltoids (front of shoulders) and triceps.
Read about muscle imbalances
and you can learn why you need to work on your pecs flexibility as well as the
strength of your scapular retractors, primarily rhomboids and lower/middle
As far as exercise form. If you are looking to work your chest with
push-ups you must have a wide hand stance.
Your elbows should be far out to the side and not in towards your body.
Start with your chest on the floor and make sure you go through as full a
range of motion, preferably touching your chest towards the floor each
Another option is to get push-up stands or perfect - push-ups.
These elevate you above the floor and allow you to get more range of motion,
stretch your pecs and work more of your pecs muscle mass in the process.
Muscle soreness does not necessarily mean your muscles are getting worked and
definitely does not indicate if you will gain muscle.
you don't think your pecs are growing because of your inability to recruit them
work on your posture and muscle balance as well as exercise form. If you
are recruiting your chest muscle fibers and not gaining muscle, it is problem
with your diet.