What are the pectoralis muscle (Pecs): well a picture is worth a thousand words. the Pecs will roll the shoulders forward and be part of a postural change creating pain in the neck and upper back. Therefore stretching the Pectoralis minor and major muscles will decrease the stress on the neck and upperback.
Here is how you stretch these muscles.
Start lying on the floor as the picture shows, then with the back of your hands on the ground, move then SSSLLLOWLY up over your head, maintaining the back of your hands on the ground.
then you can lay on a bolster or a foam roller the length of your spine.
Another great Pec stretch is standing in a doorway, with all of these you want to hold the stretch for about 2 minutes.
As you can see on this picture the elbow is in the doorway and tail bone tucked. You can move your elbow from shoulder height to higher, maintaining the stretch in your chest area.
Prevent. Perform. Recover.
Equinox Health Clinic