Swimmers often blame their shoulder injuries on weak rotator cuff muscles. And while the rotator cuff may have become weak, it’s likely not the actual weak link in the kinetic chain. According to Physiopedia, “Most swimming injuries are classified as overuse injuries and relate to faulty biomechanics.” With this in mind, the rotator cuff muscle group is usually “shouldering the load” for a weaker area downstream: the latissimus dorsi (lats). So, if someone feels like their stroke efficiency is suddenly struggling, the first thing I want to check is their lat strength.
Signs of lat weakness
There’s one common sign that’s easy to look for on land, before even testing lat strength: posture. Colloquially, the lats are known as the “swimmer’s muscle,” and they give swimmers’ backs a nice v-shape when properly developed. Keeping this image in mind, a lack of lat strength can appear as a “swimmer’s slouch” with rounded shoulders and forward head posture. Swimming only freestyle can worsen this postural dysfunction.
Despite this evident sign, many might not suspect their lats as the primary source of dysfunction because they don’t feel the pain in their lower back, or it feels like their arms are actually weak because their freestyle pull requires significant force. But those who understand the lats function know that it’s responsible for pulling movements–one of the primary movement patterns in swimming. Therefore, power should come from the lats and not the arms. Unfortunately, lat weakness can masquerade as other problems. Some swimmers won’t realize they have suffered through it until they have biceps tendonitis or delt strains–because they relied on arm muscle to get across the pool.
You’ll want to have a personal trainer or physical therapist assess this problem if you notice:
- Pain at the front of the shoulder, which can indicate that other shoulder muscles are taking over
- Weakness with pulling or throwing motions
- Difficulties raising the arm overhead
- Swelling around the lower back, side, or shoulder area
- Large muscle spasms around the shoulder blades
Mobility restrictions
Those with lat mobility restrictions will generally struggle with:
- Shoulder adduction
- Shoulder flexion
- Trunk lateral flexion (side bending)
- Thoracic extension
Therefore, any overhead movements or rotational movements in swimming become increasingly difficult, and swimmers may push their range of motion to achieve goals. Since upper body rotation is important in swimming, those who can’t rotate from their spine will compensate through over-rotating at the shoulders or hips. The lats also attach to the pelvis, so if one side is tighter than the other (common with swimmers who breathe uni-laterally during freestyle), this can lead to a “hip hike” that throws a swimmer off balance.
Lats also play a key role in shoulder internal rotation, shoulder extension, and overhead mobility, as they attach to the bicipital groove of the humerus. Swimming relies heavily on shoulder internal rotation for all catch positions and in bringing the arm behind the back. In addition, it requires frequent overhead arm motions. Any mobility restrictions here worsen the problem, leading to wide-arm recoveries, out-sweeping or shallow catches, and shoulder impingement.
Chronic overuse affects scapular stability
What happens if swimmers keep logging thousands of yards a day and don’t fix this problem?
Leaving lat weakness unaddressed can worsen existing overuse injuries and cause new ones down the road. Long-time swimmers might have heard about “scapular dyskinesis,” where the shoulder blade protrudes off the rib cage. Often times, this happens due to long thoracic nerve damage from accidents. But sometimes, this simply occurs when scapular stabilizers (rhomboids, serratus anterior) are chronically fatigued for extended periods, as they work to keep the shoulder blade in position.
Since this significantly affects the shoulder blade’s rotational pattern, it can feel like a nightmare for swimmers: crunching, popping, clicking, and other new sounds accompany what used feel like an effortless freestyle pull. You’ll also notice increased pain with every-day activities that require prolonged shoulder elevation, such as driving or working on a computer.
Exercises that will strengthen and mobilize
If you suspect that your lats could use some assistance, here is an exercise plan you can try. Start with a light resistance and then move to medium if you do not feel nerve or muscle pain with these movements.
Warm-up:
A) Lat foam rolling (30 seconds – 1 minute)
Lay on your side, across a foam roller. Roll up to the armpit area, and down to the top of the pelvis.
B) Lat stretch on swiss ball (2 x 30 seconds, with 15 second rest between sets)
Strength exercises:
- Lat pulldown (3 sets x 10 reps)
- Forearm plank (2 sets x 30 seconds)
- Bent over row, with bands (3 sets x 12 reps)
- Tricep pushdown, with rope (3 sets x 10 reps)
- Triceps assist the lats; strengthening them will contribute to proper lat function.
Cool down:
A) Child’s pose (30 seconds)
B) Downward dog (30 seconds)