In the first two parts of this shoulder impingement series, we reviewed shoulder impingement pathology and how to address mobility restrictions commonly seen with this condition. As you may recall from the first post, shoulder strength and stability are also potential contributors to shoulder impingement. It is not uncommon to see someone suffering from shoulder impingement who has full range of motion and great mobility but lack the strength to support the motion, especially when under load (like overhead pressing). This inability to adequately support the shoulder can contribute to mechanical changes within the joint and surrounding tissue which can then lead to injury. In this article we will go over some exercises and drills for common stability issues that may contribute to shoulder impingement.

Posterior Shoulder Strength:
It’s common to see an imbalance between the front (anterior) and back (posterior) shoulder muscles. Strengthening the back deep rotator cuff and scapula muscles can reduce this imbalance and improve general shoulder mechanics. Below are some of our favorites. Other common gym exercises to work on posterior shoulder strength include reverse flies, face pulls, pull-a-parts, and high rows.

Load Bearing Stability/Balance:
Being able to train the shoulder under load is important to return to sports and overhead weighted activities. Oftentimes, strict overhead pressing is painful for those with shoulder impingement. Fortunately, there are different ways to load the shoulder and provide a similar strengthening stimulus. Loading the shoulder and pressing also engage the serratus anterior muscle, an important scapula muscle. The video below shows some examples of loading the shoulder and activating your serratus anterior using your body weight, kettlebell, or barbell.

One important function of the rotator cuff muscles is to help stabilize the ball in the socket. A great way to train these muscles and challenge the shoulder is by increasing instability (“chaos”) through the use of bands and hanging weights. These exercises also often let those with pain under heavier loads to complete an exercise with less weight but still be greatly challenged. Below are some of the ones we like to use in the clinic. Be careful though as they are generally more challenging than they look!

Kettlebell Carries:
What’s more functional than carrying weight around? Not much. And certain kettlebell carries are great for strengthening the posterior shoulder, upper back, and rotator cuff muscles. Below are a couple variations you can try with kettlebells. You can get a similar effect by using dumbbells, barbell, or sandbags.

Not everyone will have similar benefit to each exercise as each person has different strength and stability limitations. For example, one person may have a large imbalance between the anterior and posterior shoulder muscles and may benefit more from focusing on those posterior muscles. Someone else could have great overall strength but have issues with keeping a good overhead press position. This person may benefit more from overhead carries and chaos exercises. Unfortunately, it’s challenging to tease out specifically what you need. If you find yourself unable to do so, I recommend seeing a physical therapist who can further evaluate and identify areas of weakness.

If you feel you have some shoulder weakness and dealing with shoulder pain, I hope this post has been useful. Please reach out if you have any questions!


In the first part of this shoulder impingement series, we reviewed the anatomy and mechanics behind it and possible contributors to this movement dysfunction, to include mobility restrictions. “Mobility” here is defined as the body’s ability to move through a joint’s intended range of motion. For example, knee mobility includes the ability to completely lock out the knee. An inability to do so would be considered a mobility restriction or impairment. Such restrictions can be due to limited muscular flexibility, joint capsule extensibility, altered joint structure/mechanics, postural limitations, or a combination of all the above. In this article we will go over some exercises and drills for common mobility restrictions that may contribute to shoulder impingement.

Pectoralis Major/Minor Tightness:

The way the pec muscles sit across the chest and attach to the upper humerus (pec major) and scapula (pec minor) can impact overall shoulder position, decreasing the available sub-acromion space. Decreased space here provides less “room to breathe” as we raise our arms past shoulder height. Check these out to help improve pec major and pec minor flexibility.

Latissimus Dorsi Tightness:

Although the lats are a “back” muscle, the muscle actually attaches towards the front part of the upper humerus. Therefore, along with restricted pecs, it can also pull the shoulder forward and decrease the available space. Here are few options to improve lat flexibility.

Thoracic Extension Restriction:

In Part 1 we discussed how the shoulder complex includes how the shoulder blade glides along the rib cage. The shoulder blade’s ability to do so partially depends on the thoracic spine’s ability to extend (bend upright/back). We oftentimes see patients and clients with more of a flexed forward posture and “stiff” going back. Here are a few of my favorites to improve thoracic extension.

Limited Shoulder Internal Rotation:

Internal rotation is the ability to rotate your hand towards your stomach or reaching for your back pocket. It can also indicate limited extensibility of the posterior (back) shoulder capsule. Restrictions can theoretically push the ball of the ball-and-socket joint forward, possibly creating irritation to the front shoulder structures. Here are some of our favorites to address this restriction.

Limited Shoulder External Rotation:

External rotation is the ability to rotate your hand out or cocking back as if throwing a ball. It is also responsible for being able to point your armpits forward and keeping elbows in when pressing overhead. Limited external rotation results in overhead movement dysfunction that can lead to shoulder impingement symptoms. Below are some exercises to work on this.

Everyone is unique, and not everyone will need the same flexibility exercises and mobility drills. If you feel you are “stiff” in an area or two, try out the associated exercises in the videos above and see how it feels. One way to assess if an exercise is beneficial is simply by testing and retesting a potential painful or “stiff” movement: try the movement (ex: overhead pressing), complete mobility work to address the restriction (ex: thoracic extension drills), then retest the movement. If the movement feels better, then it may be worth working on further.

If you feel you are restricted and dealing with some shoulder pain, I hope this post has been useful. The next part of this series will be geared towards shoulder strength and stability. Stay tuned!


Shoulder impingement is arguably the most diagnosed musculoskeletal shoulder issue, especially in the functional fitness, weightlifting, and tactical worlds requiring repetitive overhead movements and heavy loading. Unlike most other musculoskeletal diagnoses, shoulder impingement is more of a biomechanical syndrome and movement dysfunction than an actual anatomical pathology. This is important to understand because, despite having the same diagnosis, those suffering from shoulder impingement can have varying impacted structures, symptoms, limitations, and causes. The goal of this article is to provide this physical therapist’s general overview of shoulder impingement and potential causes. Future posts will focus on possible treatment strategies based on identified impairments and limitations.

When researching shoulder impingement, you may see more specific diagnoses including internal versus external impingement. For this series, we will discuss external impingement, which is predominantly seen in these communities.

Simply, impingement, like the word “impinge” implies, is a mechanical encroachment or invasion of space in the shoulder, primarily in the sub-acromial space between the ball-and-socket joint and the acromion (boney roof over the joint). This encroachment can increase friction and pinch the structures running through this space. These include the joint capsule (the bag that wraps around the ball-and-socket joint), rotator cuff muscles and tendons, bursa (fluid filled sacs to reduce friction), and one of the two bicep tendons. The body is usually resilient enough to withstand the occasional pinch and rub, but repetitive exposure overtime develops associated pathology like tendonitis, bursitis, and microtears.

Fortunately, shoulder impingement is dependent on motion and is not a constant, always present, encroachment unlike a large disc bulge pinching a nerve. Typically, the sub-acromial space is unimpacted when the shoulder is resting, and most folks dealing with impingement are fine if the arm stays at or below shoulder height. Why is this? Well, like mentioned earlier, impingement is a mechanical syndrome; therefore, symptoms are dependent on shoulder motion (aka shoulder mechanics). Let me further elaborate.

The shoulder joint is more than just the ball-and-socket joint. It also consists of the acromioclavicular joint (aka AC Joint, where collar bone meets the shoulder blade) and the scapulothoracic joint (the shoulder blade floating along the rib cage). For you to raise your arm overhead, motion occurs in all three, especially the ball-and-socket and scapulothoracic joints. Initial movement is primarily the ball rotating and gliding in the socket; however, that only accounts for about 50-70% of the movement, depending on which way it is being raised. The rest of the movement comes from the shoulder blade gliding along the rib cage and rotating in order to point the socket upward. Shoulder impingement occurs when this combination of joint movements isn’t clean and the humerus (arm bone) jams up against the acromion, pinching all the structures between. Let’s take a moment to review some potential reasons this occurs in different individuals and why treatment needs to be individualized based on the person’s impairments and not the diagnosis alone.

Mobility, or lack of, is often a contributing factor to shoulder impingement. We will see folks strong as ox in their readily available range of motion; unfortunately, they oftentimes lack the mobility to easily get into a full overhead position with pressing, snatching, and pull-ups. Common contributors include tight muscles connecting directly to the humerus (ex: lats, pec major) and limited extension of the thoracic spine (mid/upper back). Additionally, postural limitations can play a big impact as it impedes the scapula’s ability to glide and rotate. Ideally, at rest while sitting or standing upright, the shoulder blade is vertical. With a rounded upper back and forward-dumping shoulder (commonly seen with a slouched position), the scapula is no longer vertical and now tilted and rotated forward. This puts the shoulder in a disadvantaged position as the scapula is now unable to fully point the socket upward when raising the arm overhead. To illustrate this, sit/stand with “perfect” posture then raise your arm overhead. Now, sit/stand with “bad” posture (think Hunchback of Notre Dame) and do the same. Feel the difference?

Not everyone with shoulder impingement needs mobility work because not everyone is “tight”. Plenty of weightlifters and CrossFit athletes have the available range of motion to get into these overhead positions; however, they may lack the strength and stability to support the movement, especially under load. Insufficient strength can alter the movement mechanics and rhythm of shoulder elevation or prevent unwanted micro movements within the joint. An example of altered mechanics may be decreased strength around the shoulder blade, impairing its ability to glide and rotate smoothly and timely along the rib cage. If the rhythm is off, the scapula will not be able to move the acromion out of the way in time as the humerus continues to rise, resulting in impingement. If the person has good strength and mechanics to get overhead, they may lack stabilizing strength while in that position under load. For example, the rotator cuff muscles ensure the ball is and stays seated in the socket. Weakness here can create micro movements within the joint that can result in impingement. So, as you can see, not  everyone with shoulder pain is tight and needs to perform banded distractions from the pull-up bar.

The last contributing factor to shoulder impingement I want to quickly address is general positioning and control. Individuals that fall into this category have the readily available range of motion and strength to support the movement but have some possible movement flaws that place their shoulders in a vulnerable position. For example, I may see an athlete who only has pain at the end range of overhead pressing. When reviewing their press, they press beyond the vertical position (bar directly overhead with bar, head, shoulders, torso stacked in line when viewed from the side) and actually end with the bar more rearward, placing more strain on the shoulder by jamming the humerus into the acromion. We will see similar issues with snatches and overhead squats, especially in the bottom of the squat position. Another example is kipping pull-ups where the athlete generates too much swinging momentum with their torso and lower body resulting in excessive overhead flexion. Unlike the mobility and strength impairments previously discussed, these are treated with proper coaching, cuing, and consistent clean repetitions under lighter loads.

In summary, shoulder impingement is a mechanical syndrome and not an anatomical diagnosis. It occurs when repetitive strain is applied to the structures located in the sub-acromial space. Contributing factors can vary and include mobility limitations, strength deficits, and movement flaws.

I hope you have found this to be useful. Stay tuned for future articles with ways to address these impairments!

Dr Pat Casey PT, DPT, OCS, CSCS