Tight shoulders restrict athletic performance and our daily activities. A key aspect of upper body health is to have full shoulder flexion, meaning you’re easily able to lift your arms straight up over your without arching your back. If you are interested in contortion, handstands, or advanced yoga poses you will want even more range, building the ablility to move your arms behind your ears with strength and good form.
There are a number of different structural and muscular factors that can restrict mobility here including the ability of the scapulae to rotate upward and correctly position the shoulder socket (see my blog post on shoulder anatomy for more info about this), instability in the rotator cuff muscles leading to tightness (see the rotator cuff post for more info), and tight lats, among others.
But today we are going to talk about a reasonably common cause of decreased mobility with a relatively easy short-term fix (yay): stretching the pectoral muscles.
What is the Pectoralis Major?
The pectoralis major muscles connect the front of the upper arm bone (humerus) to the bones of the front of the rib cage and the clavicle. It is one of only two bones that connect the arm to the torso rather than the scapula, and it’s a big, powerful muscle capable of lifting a lot of weight. This is the muscle that leads the way for weighted movements like push-ups and bench presses.
The pec major is a pretty common muscle to be highly active and over-worked. Lots of people train push-up style exercises without doing a corresponding amount to work the back of the body. Exercises like benching heavy or continuous sun salutations bias these muscles. If your form is off and your back muscles aren’t active, or your shoulders are forward rotated because of poor posture, those pec muscles can get very stressed out and tight.
How Does the Pectoralis Major Effect Shoulder Flexibility?
Since the whole job of the pec muscle is to pull the arm in towards the body, it makes sense that they could get in the way of that overhead shoulder flexibility. Tight pecs will pull the arm bone in and down, creating a concave chest, hunched shoulders, and forward rounded scapulae. Then when you try to stretch your arms overhead they may feel very heavy, blocked, or pinchy, and it will be hard to straighten your elbows and find external rotation.
For folks with chronically tight pecs, a relatively quick stretch of the pectorals can immediately confer a satisfying increase in range of motion of the shoulders. For my favorite pec stretch (I call it the clock stretch) check out the video below. All you need is a wall to do it, and it targets all the different fibers of the pectorals and even gets a little bit into the pec minor which runs underneath the pec major and is a big contributor to hunchy shoulders.
This is a Short-Term Fix!
Pro tip: the gains provided by the clock stretch can potentially feel miraculous, but they do not address the root causes of your tight pectoralis muscles!
If you find that the clock stretch provides a noticeable improvement in your shoulder flexibility I highly recommend that you take a look at your posture and training regimen in order to figure out why they are tight.
Passive stretches like the clock stretch are great quick fixes. They can feel good and provide windows of opportunity to try out greater ranges in our joints, but they don’t change our bodies’ fundamental configuration. Sleuthing down the root causes of tightness will give you a more sustainable change and ease of movement in the ranges you desire.
For ideas on how to create more stable, mobile shoulders and address your root causes, please check out our catalogue of shoulder mobility videos at Video Club.