by Dzuka Lin, PT at Action Reaction Physical Therapy
There are a lot of benefits of the Shoulder “W” exercise. The exercise combines shoulder external rotation with scapular retraction and posterior tilt, definitely a great benefit as it recruits the posterior rotator cuff (infraspinatus and teres minor) and the lower trapezius, which I emphasize for a significant number of my patients, including post-op/pre-operative shoulder patients and patients with impingements.
A study by McCabe et al (NAJSPT 2007) demonstrated that the shoulder W exercise exhibited a moderate amount of posterior rotator cuff and lower trapezius EMG activity. But more notable for me was the finding that this exercise produced minimal upper trapezius activity and the highest ratio of lower trapezius to upper trapezius activity. It has been found that upper trapezius often overworks more than the lower trapezius and may cause a muscle imbalance. This imbalance often leads to impingement of the shoulder (supraspinatus and biceps tendon to be more specific), so that explains why I like an exercise that really emphasizes the lower trap and posterior rotator cuff, especially since a lot of us (but not all of us) are people weighed down by gravity, which pulls us forward so we develop a nice hunched over “cooked shrimp” posture.
How to do a good shoulder “W” exercise
I grasp a good piece of Theraband about shoulder width apart and hold with my thumbs up. I’ve seen many people recommend that you point your thumbs back, I don’t really think that supinating your forearm changes the exercise so I’d rather keep the forearm in neutral and really just focus on the shoulder and scapula (don’t cock the wrist forward or back)
The other tidbit I would recommend, and the origin of the name “W” exercise, is that I like to keep a 90 degree angle at the elbow, which ends up form a “W” when you reach end range of external rotation. This happens because the lat muscle mass causes your arms to abduct a little bit of your body. I wouldn’t recommend trying to keep your forearms parallel to the ground.
If you perform the shoulder W exercise with thumbs back and keep your forearms parallel to the ground (and thus don’t form a “W”) I feel that you are really missing out on the scapula retraction and more importantly, the scapular posterior tilt that you achieve when forming a “W.” Give it a whirl, and you’ll see what I mean.