What are the Shoulder External Rotators?
The most common rotator cuff muscles people tend to have weakness in is their shoulder external rotators (infraspinatus and teres minor). These constitute two of the four muscles in your rotator cuff. When these muscles can’t produce enough force, they can be easily overpowered by the bigger muscles around your shoulder such as your pecs, lats and deltoid and can lead to shoulder impingement/pinching/pain. The best staring point for this issue is to increase the force generating capacity of the external rotators aka their strength.
- insert photo of infraspinatus, teres minor
In order to build strength in these muscles we need exercises that load isolated shoulder external rotation. There are a two main options for loading – resistance bands or dumbbells. My go-to starting option would be with a resistance band, which I will then progress to loading with dumbbells. In some situations, a resistance band is too much load and you may need to start with isometrics – I will also discuss when this is required.
How to Perform Shoulder External Rotation with a Band
You’ll need to secure a band at roughly elbow height. A rolled towel is crucial to make this exercise work better. As you firmly squeeze on the towel, you better isolate a pure rotation movement vs a whole arm swinging movement. If you don’t use the towel, your deltoid will take over and you won’t recruit your external rotators as effectively (you’re cheating!). You also need to stabilize your scapula (shoulder blade) by pulling it back and holding throughout the whole movement. This greatly improves the leverage of the external rotators as these muscles originate on your scapula. Finally, you must feel this exercise on the back of your shoulder blade (where these muscles are located). If you feel it in other areas (front of shoulder, lateral shoulder or into your arm), you need to re-adjust.
– insert video for resistance band external rotation
- Secure band at elbow height
- Place rolled towel between elbow and side
- Grab band with elbow bent to 90 degrees
- Start with some tension on the band with arm in front of your belly
- Squeeze shoulder blade back and hold
- Squeeze elbow firmly into the towel as you pull the band out to the side
- Hold 5 seconds at the end point
- Return to starting position while keeping your shoulder blade back and maintaining the squeeze on the towel until your hand is back in front of your belly.
Re-adjustments to try if you don’t feel it in your external rotators
-embed video for adjustments to resistance band external rotation
- start with less tension on the band
- Move through a smaller arch of movement – stop at a position before you feel all the “wrong” muscles kicking in.
- Switch to a lighter resistance band
If the re-adjustments don’t work, then you are not ready to load with a band and need to do isometrics instead. Isometric exercises involve engaging your muscles without any movement. This allows you to start with the exact workload that your external rotators can produce without calling on other muscles in the area to take over and cheat.
How to Perform Isometric External Rotation
- embed video for isometric external rotation
- Place rolled towel between elbow and side
- Bend elbow to 90 degrees
- Place the end of your forearm/wrist on a doorframe or wall
- Squeeze your shoulder blade back and hold
- Squeeze firmly on the towel (with your elbow) and hold
- Gently press wrist into doorframe/wall, thinking about twisting your arm into external rotation while maintaining the squeeze on the towel
- You can use your opposite hand to help palpate your external rotators to help with the “feel” of these muscles
- Press as strongly as you can while maintaining isolation of your external rotators – this could be 10% effort or less to start with
- Once you are able to do this with 50-75% effort for all of your sets/reps, you are likely ready to start band work
Using your other hand to palpate your external rotators can be useful to restore your brain’s awareness of these muscles. When a muscle becomes very weak, your brain often loses some of the sensory map/awareness of these muscles. Using tactile feedback from your hand while you do this exercise can help rebuild this awareness.
Once you find band external rotation is no longer challenging, it is time to progress to dumbbell external rotation. With a dumbbell you MUST lie down on your side for this to work. I have seen many therapists, trainers and fellow gym goers perform neutral dumbbell external rotation in standing – this is a waste of your time. If a physio or trainer is prescribing these, they clearly slept through their biomechanics classes! Check out this article to find out why (insert link to DB ER error)
How to Perform Side Lying Dumbbell External Rotation
-embed video for dumbbell external rotation
- lie on your side with rolled towel between elbow and side
- Hold weight with elbow bent to 90 degrees
- Roll body forwards slightly
- Squeeze elbow firmly into towel as you lift the weight up over the course of 2 seconds
- Pause and squeeze your external rotators for 1 sec
- Keep squeezing the towel as you slowly lower the weight down over the course of 3 seconds
Programming Shoulder External Rotation Isometrics and Resistance Band Work
Sets: 3
Repetitions: 10-15
Hold: 5 seconds
Rest Interval: 30-90 seconds between sets
Frequency: minimum 3 times per week (ok to do daily)
Programming Shoulder External Rotation with Dumbbell
Sets: 3
Repetitions: 10-15
Tempo: 2 seconds up, 1 second pause, 3 seconds down
Rest Interval: 30-90 seconds between sets
Frequency: 3 times per week on non-consecutive days
Your external rotators are more of an endurance-type muscle group and respond best to relatively lighter loads and higher rep ranges – it is not useful to do 5 sets of 5 reps with these as you might do with a bench press or squat! For intensity, we want an effort level of 7-9/10 (0 = no effort, 10 = max effort/failure) by the time you have finished the last repetition of your 3rd set.
For information on how choose the appropriate weight and progress dumbbell work, please refer to this article
- insert link to select and periodize weight
If you plan to do some external rotation work as a part of your usual workouts, save it for the end of your workout. If you pre-fatigue these muscles before doing any upper body work (bench press, shoulder press etc), you will likely compromise the ability of these muscles to stabilize/control your shoulder during these bigger lifts. You could however do 1-2 sets of non-fatiguing band work as a part of your warm-up.
The Foundation Has Been Laid
This rotator cuff treatment series provides you with starting off point for fixing a rotator cuff issue, but likely will not restore full function to your shoulder. Stay tuned for future posts discussing the next level of shoulder strengthening exercises that are needed to take things further.