The Rotator Cuff is a group of 4 muscles which originate from your shoulder blade (scapula) and attach around the top of your upper arm bone (humerus), assisting with all shoulder movements and keeping it stable in the socket.
The shoulder socket is known as the Glenohumeral joint, as your humeral head sits in the glenoid cavity.
There’s a mnemonic to help you remember the 4 muscles: The Rotator Cuff SITS on your shoulder:
Supraspinatus is above-the spine of your shoulder blade and is the topmost rotator cuff muscle. It helps the Deltoid lift the arm up & away from the body (abduction).
Infraspinatus is below-the spine of your shoulder blade, on the back of your body. It’s main task is external rotation of your arm, but also helps with abduction & adduction (lifting up away from the body & pulling it back down again).
Teres Minor is a small, narrow muscle which sits just underneath the Infraspinatus and attaches to the humerus slightly lower. It’s main job is external rotation alongside the Infraspinatus, but, because of it’s slightly different position it’s more active when your arm is lifted (abducted) over 90 degrees.
Subscapularis is the only rotator cuff muscle on the front of your body therefore the only one responsible for internal rotation. It’s the largest of the four muscles and also contributes to stabilisation when you lift your arm.
They’re so commonly grouped together because even though they all have their own main task, it’s very difficult to completely separate their actions. These four muscles work together every time you move your shoulder, both creating movement and by reducing unwanted/unexpected wobbles.
Our Favourite Rotator Cuff Exercise
If you’ve ever injured your rotator cuff, you’ll know how essential these muscles are – shoulder injuries are no fun at all! So, to help strengthen and maintain the health of your rotator cuff muscles the best thing you can do is to rotate your shoulders – simple!
Here’s our favourite exercise, adjust the weight to suit your level and get ready for some awesome feeling shoulders: