The shoulder complex is delicate and yet robust. It contains multiple structures and types of tissues. As swimmers, we don’t want to mess up any of these – but that is easily done through poor technique or overuse, leading to a host of injury problems. By looking at a few anatomy and functional approaches, I share with you here some insights to help you avoid injury.
Anatomy
In Part 1, I presented some aspects of the shoulder complex:
· The glenhumeral joint, made up of the glenoid fossa and the head of the humerus (a ball and socket);
· The sternoclavicular joint, made up from the clavicle and the sternum.
These are vital articular joints which allow free-flowing motion of the shoulder complex.
Within these are five key structures:
1. Articular surface – the end of the bone, smooth surface for ease of movement;
2. Hyaline cartilage – the smooth, glass-like covering at joint surfaces, made from collagen;
3. Joint capsule – in two parts: the outer fibrous membrane the inner synovial membrane;
4. Synovial fluid – the lubrication within the joint capsule, it reduces friction between synovial cartilages;
5. Synovial membrane – the connective tissue lining the joint capsule. Contact with synovial fluid.
I started my idiokinesis investigation in order to develop a better insight into how, when swimming, I use my shoulder in relationship to the other parts of my body: the hand, elbow, and the collar bone. The difficulty is, I can only concentrate on one thing at a time – while thinking about my hand, what are my legs doing? As with any difficult situation, begin with the simplest thing.
Muscles
Muscles contract or relax; reciprocal inhibition. Biceps contract, triceps relax; if both contracted at the same time, there would be no movement at the joints. This is fine for holding positions, as in yoga to hold a sustained position over time, or for squats, where hamstrings and quads contract to stabilize the leg. However, in normal movement, contractions and relaxing muscle tones happen automatically.
There are three types of contraction:
1. Isometric – contraction with no movement, e.g. holding a weight with no movement;
2. Concentric – contraction with a muscle shorting and joint movement, e.g. an arm curl;
3. Eccentric – contraction with the muscle lengthening, e.g. running downhill or quads.
A combination of these take place whilst swimming: holding a position on the water’s surface; moving the arms and legs; and rotation of the thorax. We don’t have to think about each type of muscle contraction; they are automatic. To start, let’s consider that whole picture, or sequence of movements. We can use this image to get a feel for the overall process before breaking it down to smaller parts and diving down to micro details. We will need a good model for this picture.
Mimicry is a powerful tool; we copy in order to learn. When we observe someone else performing a task, mirror-neurons fire and that’s why we can benefit from observing the masters in action. Great swimmers move through the water smoothly and efficiently and it is these swimmers who can provide our model. Visualising these swimmers’ seemingly effortless strokes, the pre-motor cortex is activated. Because the pre-motor cortex is responsible for planning our movements, the visualisation process begins the transformation. From here, the motor cortex, responsible for movement after planning, can be engaged.
In a masterclass by an Olympic swimmer, a training event set up by SwimOxford in 2016, we followed exactly this process. We observed the over-all picture of a smooth and efficient stroke, then reduced this picture down to ever smaller parts – taking that right down to our fingertips. We can use this sort of visualisation to imagine using the fingers, hand, elbow, arm and shoulder, then apply these micro-images to the greater image. Play with the visualisations, hold them in mind, then let go, swim, and notice the changes.
So these are our steps:
1. Visualise – imagine how you see yourself moving, wanting to move.
2. Mimic – copy from great inspirational leaders, swimmers.
3. Overview – think from outside the body, observation and feel from within the body
4. Breakdown – think whole motion, complete body, rhythms, tiny parts, fingertips.
I realised that knowing muscles change length in response to stimuluses being placed on them was only part of the picture, especially as all this happens long before we become aware of it. For this article I will now let the sub-conscious autonomic responses do their job. As for being mindful of techniques: yes, to one at a time; yes, to organising the bones, joints and muscles in relationships to each other; and yes, to visualisations.
When considering the shoulder complex, the lesson is this: do not think of the shoulder as a group of muscles at the top of the arm; it is much, much more than just the rotator cuff muscle. An awareness of the different parts of the shoulder, of how they function together and with the rest of your body, is at the core of a smooth, efficient and injury-free swimming experience.
Post written by Darrin Roles