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  • Writer's pictureUltra Sports

Why does my shoulder hurt while swimming?

Updated: Feb 10, 2019



That triathlon and ironman is looming: you’re running fit, (you’ve successfully avoided straining that calf again), you’re cycling fit, (the knee has been holding out well) and you were swimming fit until your shoulder started hurting.

This is the way it usually goes: you swim the lengths, you do the drills, and you expect to get to the end of an event (even the end of the season) without any hiccups. Fair enough. But then one morning during training you notice a recurring niggle in your shoulder as your arm passes a certain point in the swimming stroke.

Over the course of the next few training sessions it gets worse, you possibly start feeling a nagging ache or the pain with specific movements during the day, and so it gradually deteriorates until swimming training is almost impossible.

What has caused my shoulder pain?

You have developed “swimmer’s shoulder”. This is a generic term indicating pain in the shoulder, usually nearer the front of the shoulder. There are a variety of issues that can cause this pain, most often through some form of impingement.

Let’s look at the basic anatomy of the shoulder joint.


It’s a pretty tight fit, which means that it is essential for all the structures to work in perfect harmony to prevent injury.

Prevention is better than the cure. Yes it’s a cliché, but clichés only become clichés because they are true! How do you prevent your shoulder from becoming your Achilles’ heel?

Broadly speaking, there are a few possible scenarios to avoid:

1) Doing too much too soon:

Do not increase your training distance suddenly if the muscles do not have the necessary strength or endurance; or be sure to allow enough recovery time between training sessions. Pace your training.

2) Not using your body correctly:

Be sure your swimming technique is good. Poor form will most certainly lead to straining of the tissues in the shoulder.

3) Applying excessive force on the structures by using inappropriate training tools:

One example would be the use of training paddles. There certainly is a place for this, but don’t overdo it.

4) Returning to swimming after a prolonged period of rest:

The muscles will have lost strength and endurance and to a certain extent muscle memory. Don’t rush into picking up training where you left off.

The arms are responsible for most of the propulsion in all four swimming strokes, so not only is there a huge load placed on the shoulder joint, but it is done so repetitively, in an overhead position. To look more closely at protecting the structures of the shoulder, it’s important to understand the basics of the functional shoulder girdle.

In order for there to be good range of motion in the shoulder, the top of the arm (humeral head) has to be held very securely and in a very specific position in the socket. This is achieved by the action of the various muscles surrounding the shoulder joint and the joint capsule. If there is tightness or laxity in any of these structures, the humeral head will shift as the shoulder moves, causing impingement and/or pain.

The shoulder blade (Scapula) also plays a vital role in enabling movement in the shoulder; it provides the socket for the humeral head, so it has to be stabilised in specific ways to allow the shoulder joint to move freely.

These two groups of muscles (those moving the humeral head in the socket and those stabilizing the shoulder blade) have to work together to allow for the free motion that is required to complete the swimming stroke. For a better understanding of how the shoulder blade moves when the arm moves, click on the animation link below.


What can you do to ensure these muscles are all playing their part? This is a very complex area, with a vast array of exercises and bits of advice that would be relevant.

For the scope of this blog, let me highlight just a few of the possibly lesser known common problems and how to prevent them.

A quick disclaimer: the demonstration videos I have selected below are examples of what may help, but generally it really would be better to see one of the Physiotherapists or Strength and Conditioning specialists at Ultra Sports Clinic to provide you with advice and exercises that best suit your needs, and possibly some form of soft tissue treatment too.

Problem 1: Tight muscles in the front of the chest, especially Pectoralis Minor. Looking at the image you will see it attaches to the Coracoid process in the front of the shoulder, which is actually part of the shoulder blade.


If this muscle is tight it tilts the shoulder blade, reducing the space in the shoulder, and may potentially result in impingement.

What causes this? Slouched or forward posture is possibly the main culprit (the shoulders roll in and this muscle becomes shortened); you could be overtraining the muscles of the chest; and/or maybe you’re not stretching enough.

What can you do? If you spend many hours sitting or standing at a desk, be conscious of your posture, and frequently roll your shoulders back. Stretch the muscle regularly, before you develop problems.

For an excellent video demonstration of the stretch, see video link below. Note the care taken not to overstretch the shoulder joint capsule to the front of the shoulder. (Apologies for the loud intro to the video!)


Problem 2: Under active or weak muscles that help to stabilize the shoulder blades in a “back and down” position. These are the Middle and Lower Fibres of Trapezius.


What causes this? Once again, poor posture and prolonged sitting place the muscles in the middle back on constant stretch. They subsequently become weak and are unable to maintain the necessary forces on the shoulder blade as the shoulder moves, especially when near constant force is applied to the shoulder in an overhead position, as is the case with swimming.

What can you do? Apart from the obvious “pay attention to your posture” advice, actively strengthening these muscles is essential. Not only is strength necessary, but endurance is equally important to maintain the stability in the shoulder blade when swimming for a prolonged period.

Follow the video link below to watch a demonstration of this simple, yet highly effective exercise. I’ll reiterate what he says at the end of the video: do not allow your shoulders to ride up towards your ears as the muscles become tired.


Problem 3: Another stabilizer of the shoulder blade that very often becomes weak is the lesser known Serratus Anterior. It originates on the outside of the ribs and attaches to the underside (against the ribs) of the shoulder blade.


Its job is to hold the shoulder blade close to the rib cage whilst enabling it (the shoulder blade) to upwardly rotate, which in turn facilitates overhead arm movements.

When this muscle is weak or fatigued, it can have a direct impact on the dynamics of the shoulder girdle, which once more, can lead to impingement and/or pain.

What causes this? Weakness in this muscle can be as result of damage to the nerve innervating it (the Long Thoracic Nerve), and this usually happens with some kind of trauma. However, the Serratus Anterior also has a tendency to become deconditioned through lack of use or, yes you guessed it, poor posture.

What can you do? If there is damage to the nerve, it more often than not recovers spontaneously over time. During this process, and also if the muscle has simply become deconditioned, you need to activate and strengthen it. There are many exercises that will do the trick, but this is one of my top choices (further down the line in rehab) as it works this muscle along with another (the Infraspinatus muscle) at the back of the shoulder. Click the video link to watch.


What if this advice is too late and your shoulder has recently started hurting?

Pain relief is important. Stop or modify the activity that causes pain, in this case swimming and any other exercise that aggravates your symptoms. Ice will also help reduce the pain and inflammation. Consider taking anti-inflammatory medication. Acupuncture has been shown to work well for the relief of shoulder pain … and we happen to offer acupuncture as an add-on to physiotherapy at Ultra Sports Clinic. Why not talk to us to see if this would be a suitable option for you?

It is important to find out what the origin of the problem is. This way treatment can be focussed on addressing not only the current symptoms, but also the cause and as such prevent this from becoming a recurrent problem. Seeing one of our physiotherapists for an assessment and a course of treatment (including exercise rehab) is the best way to do that.

If there are any concerns or misgivings regarding your shoulder pain, Ultra Sports Clinic does have an in-house consultant radiologist who we can refer you to, and who will be able to perform an ultrasound scan to help with diagnosis. If need be he can also administer an ultrasound guided injection into the tissue.

Hopefully you will not yet have crossed into the realms of shoulder pain. If you have, and even if you haven’t, we have a great multidisciplinary team of Strength and Conditioning coaches, Massage Therapists, a Chiropractor, a consultant radiologist and Physiotherapists at Ultra Sports Clinic to help keep you on track or to get you back there.

And if all goes well …



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