By Rob Brandham | St Kilda Rd Sports & Physiotherapy Centre | www.skrphysio.com.au
Shoulders are a complex body part. They consist of several moving parts that allow arms to move in different directions. These parts work seamlessly together to create a wide range of motions, with four small muscles known as the rotator cuff playing a key part.
What is the rotator cuff?
Shoulders consist of a ball and socket, two bone structures that are not completely congruent with each other – think a basketball trying to articulate with a dinner plate. That’s why the rotator cuff is required. These muscles are designed to pull the ball in and keep it pressed against the socket. They get their name as the muscles contribute to rotation of the arm and the tendon forms a cuff around the ball holding it into the socket. These muscles act as stabilisers, primarily helping to hold the ball in the socket rather than generating movement. This joint does not have the stability of the hip for example, where the socket is deeper and the balls fits snugly inside.
Rotator cuff injuries
Injury to the rotator cuff can come in a variety of forms. Tendon degeneration and tear, either acutely or slowly over time, is often seen in older age groups. Impingement of cuff tendons is also common. This occurs when the function of the cuff muscles deteriorates and allows the ball to move upwards and squash the tendon into the top of the socket.
Why are rotator cuff injuries common in swimming?
The nature of the swimming shoulder action requires the arm to repeatedly go through a large range of movement and pull against the water many times. When the shoulder does this it demands a lot from the rotator cuff muscles to control the movement and assist in the “pull phase” of freestyle, which can cause a degree of imbalance amongst these muscles, or even compensatory strategies if they struggle to cope. All of this can reduce the ability of the rotator cuff muscles to work effectively together. As rotator cuff muscles are involved in every shoulder movement, they need adequate strength, endurance and co-ordination to provide the required support.
Another consequence of the repetitive nature of swimming is the effect this has on other structures supporting the shoulder, like the ligaments. These gradually stretch over time, for example when the arm exits the water and reaches ahead prior to the catch, a fair amount of strain is placed on the ligaments around the joint. If these ligaments stretch then a greater demand is transferred to the rotator cuff to overcome this reduced support.
This largely depends on the degree of the damage to the rotator cuff. A significant tear may require surgery to repair, which could result in up to six to nine months out of the water. Recovery is much quicker for a minor tear, which typically needs between four to six weeks. It is important that the shoulder and rotator cuff is at full strength before returning to full competitive training to prevent further damage.
Recovery times for impingements also varies, if muscle imbalance is not considerable it can heal in one to two weeks. More extreme cases may take up to three months. Training can usually be resumed earlier, starting with pain free strokes like breastroke and as the condition improves gradually working back towards overhead strokes like freestyle.
A common mistake is not focusing on maintaining the balance between the rotator cuff muscles and having too much emphasis on attempting to increase power and strength. Rotator cuff muscles are actually quite small and work at a lower intensity for longer periods of time, therefore need to be trained in a different manner to emphasise this endurance. As the most commonly used swimming stroke – freestyle has a bias towards the internal rotation motion, there is a need to pay more attention to the external rotation element of the cuff muscles. A good test is to stand with both elbows bent at 90 degrees and have a friend resist you pushing your wrists out laterally apart from each other, if there is a significant difference between the sides or they both collapse easily with you unable to maintain the resistance for longer than 10 seconds, then there is a weakness that needs to be addressed.
Here is a link to a simple exercise you can do to target the external rotator muscles:
Also another great stretch for swimmers is the posterior capsule as this often gets tight with high volumes of training, here is a link that shows the “sleeper stretch”: