Some of these shoulder rotation exercises are derived from dance of shiva movements.
I use them in part as a shoulder awareness exercise, in part to develop better control of the shoulder rotators, including the rotator cuff muscles and also to, ideally, develop (or maintain) balance in the musculature of the shoulder.
Two types of rotation are internal rotation and external rotation. In both types the upper arm is rotated relative to the shoulder blade.
To differentiate rotation of the upper arm from rotation of the forearm focus on feeling the point of the elbow. With the arms down by the sides an external shoulder rotation will cause the elbow to point inwards. An internal rotation will cause it to point out to the sides.
Muscles that attach the shoulder blade (or scapula) to the ribcage include:
These muscles can be used to move the scapulae relative to the ribcage. They can also be used to stabilize it or fix it in place relative to the ribcage. Read more about using these muscles in scapular awareness.
Muscles that attach between the shoulder blade and the humerus include:
The first four of these muscles constitute the rotator cuff. Their tendons attach high up on the humerous close to the "ball" of the shoulder joint.
The teres major, with its tendon inserting further down the arm bone isn't included in this group even though it shares a similar name.
Other muscles that attach the scapulae to the arm bones include
The triceps long head and the biceps both attach to the bones of the forearm (the radius and ulna.)
Of all the muscles that cross the shoulder and attach the scapula to the humerus, the muscles of the rotator cuff are closest to the shoulder joint itself.
The supscapularis attaches to the front of the humerus. When it contracts it rotates the humerus internally (causing the front of the upper arm bone to roll inwards.)
The infraspinatus and teres minor both attach to the back of the upper arm bone. When contracted they rotate the upper arm bone externally.
The supraspinatus attaches to the side of the upper arm bone near the top. When contracted it abducts the arm pulling it out to the side.
When all of these muscles are contracted together so that the work against each other the feeling can be like you are tightening or squeezing the shoulder joint. You could also think of this action as "pulling" the arm into the shoulder socket.
For all of these exercises work at keeping your neck long.
Depending on whether you are doing external shoulder rotation or internal you may find it helps to either lift your chest (bend your thoracic spine backwards) or drop your chest (bend your thoracic spine forwards.) In either case work at making your neck feel long.
So that your neck and shoulders work together you may find that these shoulder exercises are more comfortable if you move your neck chest and shoulders in sync. To begin with practice just the chest (and neck) movements in isolation. Then add the shoulder rotations to that movement.
Start by lifting your ribcage and then lowering it. As you lift your ribcage lengthen your neck. As you lower your ribcage relax your neck and leg your head move forwards.
Repeat slowly and smoothly.
You may find that you automatically inhale when lifting your chest and automatically exhale while lowering it.
Start with your arms relaxed and down by your sides. Start by lifting and lowering your chest. Then as you lift your chest rotate your arms outwards. As you relax your chest let your arms relax and return to "neutral."
Notice how, in the pictures above, externally rotating the shoulders "opens" the fronts of the shoulders. If you look at the pictures below you can see that externally rotating the arms "closes" the back of the upper body, or contracts it.
In this instance my shoulder blades are squeezed together after externally rotating my arms.
Repeat slowly and smoothly.
Try the same exercise but with the scapulae retracted (pulled towards the spine.)
Next practice internal rotation with the arms down.
You can also try this rotation while exhaling, then relax on the inhale. If doing this variation then pull your chest down as you exhale rather than letting it relax down.
Notice how in the picture above, the front of my shoulders look more "closed" while internally rotated. In the picture below you can see that the back of my upper body is more open.
Initially practice rotating the arms internally and then relaxing without worrying about the position of your scapulae. Then integrate scapular control and focus first on keeping your scapulae stabilized away from the spine. Then repeat the exercise with your scapulae pulled in towards the spine.
You can do this both arms at the same time or one arm at a time.
With elbows bent you can focus on reaching your elbows down. It can be challening to isolate the upper arm, you may be just rotating your forarms. So that you know that you are using your upper arm (and thus exercising your rotator cuff muscles) focus on moving the biceps or front of the arm outwards for the external rotation exercise and inwards for the internal rotation.
For this rotator cuff exercise (with elbows bent and arms to the sides) again focus on rotating your upper arm, not just your forearms. Feel the front back of your upper arm rolling in opposite directions.
To rotate the arms with arms forwards and elbows bent, you can get the feel by rotating your arms externally with elbows straight, and then bend your elbows. (You may also find it helpful to bend your writs so that you hands have room to clear your chest.) Do the same when doing the internal rotation rotator cuff exercise.
If you look at my elbows in these two pictures you can see that in the second picture my elbows point straight ahead (arms externally rotated) while in the first picture my elbows point slightly out to the sides.
Note that internally rotating the arms with the arms up is difficult. However, if you reach the outer edge of your shoulder blade up you may find that you have room to do the interal rotation with your arms in this position. If you feel or get a sense of bone grinding against bone then don't do the internal rotation with arms up exercise.
The rotator cuff exercises above are relatively simple. However while doing them focus on "working" while inhale and then relaxing while exhaling.
While doing the active phase of each exericse, make the arms feel long and the shoulders open so that you add tension to the connetive tissue trains of your arms. In addition lengthen your spine (particularly your neck) and expand your ribcage.
When doing the active phase and relaxing phase of each exercise focus on moving smoothly between each extreme. Feel your body as you do this.
For more shoulder exercises check out the dance of shiva.