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Kinesiotape for Swimmers: Length, Strength and Timing. Part II

Take Home Points on Kinesiotape and Swimmers:
  1. The evidence does not suggest that kinesiotape aids athletic performance
  2. Kinesiotape may affect knee mechanics and improve pain in those with patellorfemoral pain syndrome
  3. Kinesiotape has been shown to increase acromiohumeral distance, potentially limiting risk for shoulder impingement symptoms. 
This is not a new topic to this blog (See Part I). But like any topic, one snapshot of the evidence is never the final word. So is there anything new to report in the literature on kinesiotape, especially as it may relate to swimming?

Overall, the general consensus is that the performance effects of kinesiotape are negligible to non-existent. Fortunately though, there appear to be no detrimental effects on performance (minus the potential opportunity cost of forgoing other potentially more effective mechanisms). 

In a recent systematic review, Drouin (2013) noted, “There is scant evidence to support kinesiotaping techniques as a successful means of affecting athletic-based performance outcomes such as improved strength, proprioception and range of motion, in healthy persons.” This appears to be definitive statement on the effects of kinesiotaping, but does it end the discussion?


One problem is that in most studies, kinesiotape is applied randomly as opposed to particular subjects for whom kinesiotaping is theorized to work. While the latter approach may sacrifice objectivity for potential bias, the latter may be more reflective of how the intervention is applied in real life. Be careful of labeling any intervention as “good” or “bad” as a blanket statement. Instead, the follow up should be “good or bad for whom?” It is a mistake to justify kinesiotape for performance based of any supporting literature for injury/pain, just as it is mistaken to outright dismiss kinesiotape as a clinical adjunct based on a lack of evidence to support performance improvements. 

Swimmers often focus on taping for the shoulder, but don’t forget the possibilities in the lower extremities, particularly for dryland and breaststroke. Song (2014) recently found that kinesiotaping caused significant shifts in patellar positioning in females with patellofemoral pain syndrome compared to the application of sham tape or a no tape condition during a single leg squat. However, both the sham tape and kinesiotape were successful in pain reduction. 

One especially pertinent study for swimming (Luque-Suarez 2013) published after our previous blog post, examined whether kinesiotape affects acromiohumerdal distance in healthy subjects (a potential measure of shoulder impingement risk). Authors of this randomized controlled trial noted that although the kinesiotape group had significantly greater increases in acromiohumeral distance compared to the sham taping group, direction of taping did not matter.

Conclusion

Overall, little has changed in the evidence on kinesiotape, especially regarding the lack of support for its theorized improvement on performance. However, recent studies have opened relatively new lines of inquiry regarding potential improvements in knee and shoulder biomechanics, both of which may be helpful for swimming health and technique.

References

  1. Luque-Suarez A1, Navarro-Ledesma S, Petocz P, Hancock MJ, Hush J. Short term effects of kinesiotaping on acromiohumeral distance in asymptomatic subjects: a randomised controlled trial. Man Ther. 2013 Dec;18(6):573-7. doi: 10.1016/j.math.2013.06.002. Epub 2013 Jul 4.
  2. Song CY1, Huang HY1, Chen SC2, Lin JJ3, Chang AH4. Effects of femoral rotational taping on pain, lower extremity kinematics, and muscle activation in female patients with patellofemoral pain. J Sci Med Sport. 2014 Jul 24. pii: S1440-2440(14)00135-2. doi: 10.1016/j.jsams.2014.07.009. [Epub ahead of print]
  3. Drouin JL1, McAlpine CT, Primak KA, Kissel J. The effects of kinesiotape on athletic-based performance outcomes in healthy, active individuals: a literature synthesis. J Can Chiropr Assoc. 2013 Dec;57(4):356-65.
Written by Allan Phillips is a certified strength and conditioning specialist (CSCS) and owner of Pike Athletics. He is also an ASCA Level II coach and USA Triathlon coach. Allan is a co-author of the Troubleshooting System and was selected by Dr. Mullen as an assistant editor of the Swimming Science Research Review. He is currently pursuing a Doctorate in Physical Therapy at US Army-Baylor University.

Are Push-Ups Safe for Swimmers?

Take Home Points on Are Push-Ups Safe for Swimmers?
  1. Push-ups are a safe and effective exercise for swimmers with proper biomechanics and programming.
Questioning the safety of push-ups seems like it would make for a rather straightforward article, and 
if it was as straightforward as it seems, I would say that they are undoubtedly safe, and an extremely effective exercise for swimmers, at that; however, we need to create some more questions in order to form an educated answer. Is the coach qualified to supervise a push-up? Do they know what to look for in the exercise? Do they understand what variations may be best for different populations? Is the athlete doing enough mid and upper back work to balance the effect push-ups may have on the muscles of the shoulder girdle? 

Is the Coach Qualified to Supervise a Push-Up and Do They Know What to Look For?

When I say ‘qualified’ I don’t mean certified in Strength and Conditioning, or having a background in exercise science, all I mean by this, is that the coach or athlete has a basic understanding of what is really happening during a push-up, and what contraindications to look for in their respective populations.

Some of the most common flaws in an athlete’s push-up pattern are: poor arm position (either too close or too far from the body), extended or flexed head position (looking up, or down too far), and the most common—sunken hips with an arched back.

When judging arm position the rule of thumb is to put 45 degrees of space between the torso and the upper arm. This 45 degree position prevents the athlete from flaring the arms out too far and therefore placing too much stress on the shoulder girdle, it also prevents the arms from being in too close, causing too much flexion at the elbow, and therefore acute elbow pain or tendinitis.

A flexed head position is caused simply by the athlete either looking to make sure the arms are in the correct spot or just general poor body awareness (very common in swimmers). The best neck position is going to be neutral, where the head is looking straight down; not down at the feet, but simply down at the ground directly below their face.

An extended neck position is the result of some poor mechanics lower in the body. When the head is hyperextended, it is generally following the rest of the spine. When the spine is hyperextended, it is generally a result of passive restraints dominating throughout the core and hips. To mitigate this, the athlete must be cued to squeeze the glutes, as well as the abs. This whole complex of muscles firing is one reason why I trust athletes who tell me they can do 5 push-ups more than those who tell me they can do 50—at this number, it is very likely that the athlete is relying on passive restraints (ligaments, tendons, and bones) rather than actively engaging the appropriate muscles, and likely shortening range of motion, as well. 

If push-ups are done correctly, it is very possible for the abs and glutes to give out before the triceps or chest. This weakness usually subsides as the athlete becomes more experienced.

Does the Coach Understand What Variations May Be Best for Different Populations?

This question is crucial. Athletes have many different backgrounds, levels of experience, shoulder pathologies, leverages, and strength—all of which can drastically change exercise prescription. Most swimmers should stick with the simplest variations of push-ups, focusing on a tight core, as well as going through as large of a range of motion as possible (without pain). Even with a basic push-up many swimmers are not strong enough to demonstrate an entire set with decent form, and in many cases can’t even perform one single repetition. Many coaches here would have the athlete do push-ups from the knees, this variation however, tends to really hamper core activation, among other things, which drastically changes the movement. I prefer to have the athlete be assisted with bands. You can do this by setting up a large band around low pegs in a squat rack, then having the athlete lay over the band so that they are assisted as they get closer to the ground, and less as they get closer to the lockout, this is known as accommodated resistance. The further up the legs/torso that the band is placed, the athlete receives more assistance, the further down, less assistance is given. If a band is not available, a secondary option is to have the athlete perform a push-up to a bench or wall. Again, the more upright the athlete is, the most assistance they are receiving, so try to work the athlete to get close to the ground, and in the banded set up, have the athlete work at lowering the band placement each session. 

Some of my favorite progressions for the exercise are: hand-release, clapping, foot-elevated, single foot, gymnastic ring push-ups. These are all rather advanced and should only be attempted after a mastery of the standard push-up is present. On the other hand, some of the best regressions are the aforementioned band-supported, and incline push-ups (to a wall or bench).

It is very possible that having the hand on the ground during the push-up can irritate the athlete’s wrist. In this case, I suggest using dumbbells, placing them slightly outside of shoulder-width, and having them turned so that the hands can be slightly supinated—this will further reduce pain/ joint problems. Dumbbells with hexagonal bells are ideal here because they won’t roll away from the athlete during the movement. 

Is the Athlete Doing Sufficient Upper and Mid-Back Work to Balance the Effects of the Push-Ups?

Push-ups are partially so awesome because they can be done anywhere that there is the space to perform them, but what is not so awesome is that push-ups can make up far too much of a swimmers dryland program because there may be very restricted access to further equipment. Too many pressing exercises can pull the shoulder girdle forward over time causing pain, as well as poor performance. To counter problems associated with this, we must make sure that enough work is in place for the mid and upper back to keep the shoulder girdle in a neutral resting position. Many strength coaches go as far as saying that the ratio of pulling to pushing exercises should be 3:1, I however, think 1.5:1 is more reasonable, as long as the athlete already has a decent resting posture. 

This back work should hit the lats, traps (upper, mid, and lower), rhomboids, and rear delts. Great exercises for this are dumbbell rows, pull-ups, chest-supported rows, rear delt raises, among others. There are thousands of variations to the exercises already listed, focusing on these, and variations thereof, will give you enough dryland programs to last for years. 

Many argue that the demands on the back are high enough in swimming that there should be a reduction in back work during dryland to compensate. The work done by the back in swimming is usually too low in intensity/load to make significant hypertrophic differences, plus the fact that outside of the pool time, many athletes are in a state of flexion, be it at a desk at work or school, at home watching tv, or driving, which all needs to be accounted for (the 22 hours outside of practice are frequently overlooked during program design). 

The push-up is a fantastic exercise for swimmers and should be a mainstay of a swimmers’ training programs. Proper coaching of the exercise is more likely to determine its safety and effectiveness more so than any other factor. Keeping exercises balance is another huge key to long-term athletic development and safety, so be sure to implement a full dryland regimen to improve body awareness, speed, and conditioning.

Written by John Matulevich a powerlifting world record holder in multiple lifts and weight classes, as well as a Head D-2 Strength Coach, and previously a nationally ranked college athlete. His concentrations are in sports performance, powerlifting, and weight training for swimming. To learn more about how John trains his athletes, check his Twitter page: @John_Matulevich. He can also be reached at MuscleEmporium@gmail.com with inquiries.

Friday Interview: Dr. Lizzie Hibberd Discusses Swimmer's Shoulder Prevention

1. Please introduce yourself to the readers (how you started in the profession,
education, credentials, experience, etc.).

Hello all! My name is Lizzie Hibberd and I am currently serving as an Assistant Professor and the Director of the Athletic Training Research Laboratory in the Department of Health Science at The University of Alabama. I received my B.A. and M.A. degrees in Athletic Training from the University of North Carolina at Chapel Hill (2008 and 2010) and received a Ph.D. in Human Movement Science from the University of North Carolina at Chapel Hill in 2014.

My interest in athletic training began when I was in high school. After injuring my shoulder and relying on the help of athletic trainers for evaluation and rehabilitation, I began working as a student athletic trainer. From my experience as an injured athlete and working as a student athletic trainer, I chose to attend UNC-Chapel Hill and started in the Athletic Training Program. After undergrad, I stayed at UNC and worked as a graduate assistant athletic trainer for UNC’s Swimming and Diving and JV Basketball teams. As soon as I began working with the UNC Swim Team, I realized there was a huge gap in the literature about prevention, assessment, and treatment of swimming related shoulder injuries. In order to improve the quality of care for athletes and advance the profession through evidence-based medicine, I continued my education in the Human Movement Science Program. While in the program, my research focused on injury biomechanics and injury prevention in overhead athletes- primarily swimming and baseball.

2. You have been the predominant researcher in the US on swimming shoulder injuries. What have been your pieces and interest in the sport?
My interest in the sport developed when I was working as an athletic trainer with the UNC Swimming Team. This was really my first exposure to the sport, where I understood the demands that were placed on the athlete. The first few months were definitely a huge learning curve for me to really understand the training and the culture of the sport. During this time, I developed such an appreciation for a sport that very few people know anything about. As I was treating athletes and trying to develop injury prevention programs, I discovered that there was a huge gap in the literature related to swimming injuries. From this experience, I decided that I wanted to focus on clinically applicable research to improve the quality of care for swimmers and other overhead athletes and began my research career on injury biomechanics and injury prevention. During this time, I have worked with youth, collegiate, and masters swimmers both in clinical and research capacities.

3. For your paper regarding the general rehabilitation program and scapular stability (dyskinesia), what did you look at?
For this paper (Effect of a 6-Week Strengthening Program on Shoulder and Scapular-Stabilizer Strength and Scapular Kinematics in Division I Collegiate Swimmers), we looked at the effect of a shoulder injury prevention program on physical characteristics in collegiate swimmers during the training season. The injury prevention program that we used was adapted from exercises that have been shown to be effective for injury prevention or strengthening scapular stabilizing musculature in baseball players. The characteristics that we looked at as part of this project were glenohumeral range of motion, scapular kinematics, posture, shoulder and scapular stabilizer strength, and pain score.

4. What were the main results?
In this project, we found that overall all swimmers moved in to greater forward shoulder posture and altered scapular kinematics that promote impingement regardless of group assignment. The strengthening program that was used in this paper was not robust enough to counteract the demands of the training load during the training season.

5. How could the rehabilitation programs prescribed be improved?
From the results of this study, the biggest places for improvement is on the timing of implementation. While most swimmers take a short rest period before their training season, this may be the most beneficial time to complete an injury prevention program. During the training season, the fatigue they experience from high training loads increases their risk for the development of injury. Completing a strengthening program prior to this heavy training would put the athlete in better position to mitigate the demands of the training. During the training season, a maintenance program should be completed with a greater emphasis on stretching.

Also, the findings of this study highlighted the importance of research specific to swimmers. Many times all overhead athletes are grouped into the same category and programs that are effective for baseball players are automatically applied to swimming. The demands and adaptations are unique to each overhead sport, and research is needed specific to each sport to best help the athlete.

6. You had another study monitoring shoulder pain via questionnaire in club swimmers. What were the main results of this study?
In this study (Practice Habits and Attitudes and Behaviors Concerning Shoulder Pain in High School Competitive Club Swimmers), we looked at 13-18 year old competitive swimmers that are training on the top training level at their clubs in order to understand the culture of swimming. We found that these adolescent club swimmers have a high frequency of practices, comparable to collegiate and professional swimmers. They believe that shoulder pain is normal and should be tolerated to complete practice and are regularly taking pain medication in order to manage their pain so that they can complete practice yardage.

On the plus side, we found an association between the swimmers' attitudes and behaviors, which indicates that interventions that educate the swimmers, coaches and parents may be effective in changing their attitudes and ultimately their behaviors, and potentially changing these cultural norms.

7. As a PT, these results really upset me. What were your thoughts on the incidence of pain and current practice?
From working clinically with swimmers, I was not surprised that training with shoulder pain is the cultural norm in competitive swimmers. Currently, the training demands in these youth athletes are tremendous and so far, there is only anecdotal evidence that these training methods are effective. This high volume of training leads to alterations in physical characteristics that predispose swimmers to shoulder pain and injury. In the future, I hope coaches and researchers partner to identify training methods that maximize performance while minimizing injury risk. This will take a lot of collaborative work, but I will be imperative in preventing these injury and making evidence-based practice and injury prevention guidelines.

8. If a swimmer is having pain in their shoulder in practice, in your opinion, what should the coach do?
I think the biggest thing that the coach can do is make it known that injury prevention and awareness is a priority. It seems like many of the swimmers that I have previously worked with (across levels) are afraid to tell their coach or don’t even think that it is something they should report because shoulder pain has been normalized in the sport. It would be beneficial for coaches to have education sessions with their athletes, or even better bring in a sports medicine professional, to talk about shoulder pain and injury prevention.

If an athlete does report true shoulder pain, where they are having pain and altering their stroke mechanics in order to complete the necessary yardage, the coach should remove the athlete from practice for that session, have then kick (not with a kickboard because that is impingement position!), or have them do some type of cardio out of the water. Removing from practice is only one part of the solution, though. The coach should talk with the athlete to determine what bothers them and evaluate how dryland training, weights, or specific swimming drills may be contributing to their pain. Making these alterations would benefit that specific athlete, but also others who are not reporting their pain. It would also be imperative for this athlete to begin a rehab program- which is where a sports medicine professional (physician, athletic trainer, or physical therapist) would be crucial.

9. Recently, you were part of a study monitoring stroke biomechanics in college swimmers. What did this study look at and find?
In this study (Prevalence of Freestyle Biomechanical Errors in Elite Competitive Swimmers), we evaluated the prevalence of biomechanical stroke errors in collegiate swimmers using underwater cameras. We focused primarily on freestyle, because of the heavy training load in the freestyle stroke regardless of stroke specialty. Both coaches and an athletic trainer graded each swimmer based on the defined errors. The biomechanical errors that we defined were a dropped elbow during the pull-through phase, a dropped elbow during the recover phase, an eyes-forward head-carrying angle, incorrect hand position during hand entry, incorrect hand entry angle, incorrect pull-through patter, and inadequate body roll. We found a high prevalence of errors in these elite swimmers, with dropped elbow during the pull-through and the recovery phases with the highest prevalence. We also found relationship between dropped elbow during recovery and improper hand entry position and angle and eyes-forward heady carrying angle with incorrect pull-through pattern. This indicates that presence of one of these errors is related to having an additional error.
 
10. Did these results surprise you?
Not really. From previous work that we have done, most youth athletes believe that there is not enough time spent on technique work in practice. I think there is so much emphasis on the number of yards that the quality of the yards is sometimes put aside. Further, the errors that we identified were from a variety of coaching and biomechanical literature, but to our knowledge a comprehensive list of stroke errors related to injury had not previously been created. Finally, some of the coaches the evaluated the videos commented that while they understood why this was biomechanical error, performance-wise it was how they taught the stroke. This is another area of opportunity for biomechanists and coaches to work together to identify ways to maximize performance while minimizing injury risk.

11. What steps can be made for improving biomechanics in college swimmers?
In my opinion, the biggest way to improve biomechanics is to put an emphasis on it in age-group swimming. It is hard to change the motor patterns of a collegiate swimmer, who may have been swimming with a certain stroke for 13+ years. However, if you do have an athlete that you want to focus on changing their stroke, I believe video is one of the most important tools for the athlete. Many athletes, and especially swimmers because they rarely get to see their stroke, respond well underwater video where they see the problem in their stroke, as well as have their progress tracked as they make the change. While there are many expensive software and cameras out there for this, things like GoPros and even iPhones with an underwater case may be adequate as a beginning step in film evaluation.

12. Same question, but with age-group swimmers?
This is the place where there is the greatest opportunity for installing proper swimming mechanics and making changes! An emphasis on proper stroke regularly during practice, individual work if necessary, video analysis, and modeling of proper strokes is imperative at this age. Ensuring proper mechanics before moving on to high yardage is critical.

13. What research or projects are you currently working on or should we look from you in the future?
I recently completed a project tracking youth swimmers over the course of their training season to identify what physical characteristics change during the training season and how this relates to alterations in pain levels and another project tracking postural changes in collegiate swimmer during the season. The findings from this study will help in developing evidence based injury prevention programs.

My future research agenda includes: validation of an evidence-based injury prevention program, development of a swimming pain and function survey, prospective analysis of risk factors for injury in competitive swimmers, and research on training load and recovery. All of these areas/projects will hopefully help in maximizing performance while minimizing injury risk in competitive swimming!

Thank you for the opportunity to discuss my research with you! Please feel free to contact me with questions, research ideas, or comments.

Elizabeth Hibberd, PhD, ATC
The University of Alabama
483 Russell Hall
Box 870311
Tuscaloosa, AL 35487-0311
eehibberd@ches.ua.edu
205-348-7320

Closed Kinetic Chain Upper Extremity Testing for Swimmers

Take Home Points on Closed Kinetic Chain Upper Extremity Testing
  1. Predicting injury has been difficult in swimming
  2. Closed kinetic chain upper extremity testing may help identify factors in the future
  3. Recent literature shows differences in upper extremity stability between males and females
Preventing injury remains a daunting task for coaches at all levels.  Though more information continually emerges to help us identify swimmers at risk, the process remains an imperfect science.  As Dr. Mullen and I wrote in the opening to the Troubleshooting System

"Injury and poor performance often result from unchecked movement dysfunction. While smart training remains paramount, coaches should be heartened that overuse is not the cause of all injuries. Training exposes movement deficiencies. Greater training demands require a higher physical preparedness standard."

One form of testing that has been gaining acceptance in land based sports with upper
extremity demands has been closed kinetic chain testing.  Such testing is common for lower body dominant land sports, as most of the injuries occur in a closed kinetic chain for the lower body (Squat mechanics assessment is one common example).  However, most upper body demands occur in an open kinetic chain (distal point not fixed).  Swimming presents an interesting case, for although the hand is never truly fixed to an anchor like the foot is to the ground, there are elements of anchoring in the swim stroke, particularly underwater when we talk of “catching” and “holding” water.   

Though literature is relatively new in this area for swimmers, some data is emerging.  Butler (2014) studied male and female division I swimmers and assessed all subjects in the upper quarter Y balance test (UQ-YBT).  The UQ-VBT involves upper extremity stability in the closed chain and examines reach distance in three directions: medial, inferolateral, and superolateral.  Essentially, the subject/swimmer is asked to reach in different directions while supporting himself/herself with a stationary anchored arm. 


Results indicated, “Average scores in the medial and inferolateral directions and composite score were higher in men than in women." (this means the only measure not shown to have significant gender difference was superolateral).

Though these patterns don’t exactly mimic the swim stroke, the results do suggest greater stability in males with greater reach in different positions.  This study only tracks gender difference and does not directly aid with injury prediction, but future literature may lead this direction.  (For additional discussion on injury prediction factors see Dr. Angela Tate interview).

Despite the lack of predictive literature thus far for the UQ-YBT and swimmers, we do know that significant differences do exist between genders in this sample.  Now, its unclear if we can generalize this across the entire swimming population, as we don’t know how these swimmers were coached leading up to the study (same coaching staff, same dryland staff?), but there are significant differences to suggest gender may indeed be a critical factor in planning dryland training. (See Should Females Train Differently Than Males, Part I, Part II, Part III)  

References


With many teams nearing the end of summer season and with a fresh fall/winter on the horizon, consider closed kinetic chain upper extremity testing as part of your team’s preseason intake.  Not only can such testing help organize information as a preseason baseline, it can also help guide return-to-swim protocols if injuries occur later in the season.  

Reference

  1. Butler R1, Arms JReiman MPlisky PKiesel KTaylor DQueen R.  Sex Differences in Dynamic Closed Kinetic Chain Upper Quarter Function in Collegiate Swimmers. J Athl Train. 2014 Jul 11. [Epub ahead of print]
Written by Allan Phillips is a certified strength and conditioning specialist (CSCS) and owner of Pike Athletics. He is also an ASCA Level II coach and USA Triathlon coach. Allan is a co-author of the Troubleshooting System and was selected by Dr. Mullen as an assistant editor of the Swimming Science Research Review. He is currently pursuing a Doctorate in Physical Therapy at US Army-Baylor University.

Subacromial Bursa Thickness and Swimming Shoulders

Take Home Points on Subacromial Bursa Thickness and Swimming Shoulders
  1. Changes to subacromial bursa thickness correlate poorly with painful symptoms
  2. Always consider imaging changes in their full context of structure, symptoms, and training load
  3. Certain changes may be a natural adaptation to repetitive movements in swimming
Shoulder injuries are an unfortunate reality in swimming.  We’ve written about this general topic before (Radiologic Imaging and the Asymptomatic Athletic Shoulder), but have additional information to add based on recent studies and with a focus on a particular shoulder area, the subacromial bursa. 

One “en vogue” diagnosis in rehabilitation has been bursitis.  For non-radiating pain with generalized pain symptoms, many providers will simply diagnose the condition as bursitis when they can’t figure out the underlying cause.  It might be harsh to call this a throwaway diagnosis, but in some cases that’s the unfortunate reality.   While this may in fact be correct in some cases, in others it may overlook the underlying problems entirely. 

The diagnosis is only part of the story without addressing overall function (that a whole topic unto itself).  But the focus in this post will be the significance of whether changes to the subacromial bursa are meaningful indicators for painful shoulders. 

Most recently, Couainis (2014) studied 22 open water marathon swimmers competing in a 19.7km event.  Ultrasounds were taken four months and two weeks prior to the race and one week after.  Authors noted the following findings:
  • SAB (subacromial bursa) thickness is significantly correlated with kilometres swum in the pool in the preceding week.
  • SAB thickness was not significantly correlated with pain when measured prior to the race.
  • At 1 week post-race, SAB thickness of shoulders with pain were significantly greater than those without pain
Now does this mean SAB thickness is a meaningful pain indicator?  Maybe but maybe not.  Authors conclude that painless SAB thickening may be a natural adaptation to repetitive swim mechanics when viewed chronically and thus not a cause of painful symptoms.  But when viewed acutely after a triggering event, increases in SAB thickness may in fact be meaningful.  Ultimately, “these two entities can only be differentiated by clinical history and examination.”  Also consider training factors.  Although most pool swimmers won’t swim 19.7km continuous, a series of hard training bouts may cause changes to structure and trigger painful symptoms.  (See, Hell Weeks and Swimming; Hell Weeks and Swimming Revisited)   

Appreciating the connection (or lack thereof) between SAB thickness and symptoms is especially important in determining whether to have surgery and in evaluating post-op outcomes.  Remember that many clinicians, though highly competent and well meaning, may not always appreciate the specialized demands of swimming and may not be aware of structural changes that accompany swimming biomechanics.

Hodgson (2012) studied patients with full thickness rotator cuff tears detected by ultrasound, with 18 having pain and 15 having no pain.  After finding no relationship between SAB thickness, rotator cuff tears, and pain, authors concluded, “Although enhancement of the subdeltoid/subacromial bursa was common, no evidence was found to support the hypothesis that bursal enhancement is associated with pain in rotator cuff tears. It is therefore unlikely to determine reliably which patients would benefit from rotator cuff repair. Advances in knowledge Bursal enhancement and thickening does not reliably correlate with symptoms or presence of rotator cuff tear.”

Studying post-op shoulder patients after rotator cuff surgery, Tham (2013) found short term increases in SAB thickness up to six months (along with increases in tendon vascularity and posterior glenohumeral capsule thickness), but noted these changes normalized after six months.  Ultimately, there was no significant connection between structural changes and pain. 

Conclusion

Nothing here is a new message, but recent literature reinforces what had already been suggested in prior findings.  Changes to structure observed through advanced imaging are only one piece of the puzzle in evaluating painful swimming shoulders.  Key take home point is to not only to correlate imaging with clinical findings but also to appreciate how modulations to training load may affect the swimmer’s condition, as both recent and long term training may determine what is normal and what is abnormal for each individual swimmer’s shoulder.  

References

  1. Tham ER1, Briggs L, Murrell GA.  Ultrasound changes after rotator cuff repair: is supraspinatus tendon thickness related to pain?  J Shoulder Elbow Surg. 2013 Aug;22(8):e8-15. doi: 10.1016/j.jse.2012.10.047. Epub 2013 Jan 23.
  2. Couanis G, Breidahl W, Burnham S.  The relationship between subacromial bursa thickness on ultrasound and shoulder pain in open water endurance swimmers over time.  J Sci Med Sport. 2014 May 20. pii: S1440-2440(14)00087-5. doi: 10.1016/j.jsams.2014.05.004. [Epub ahead of print]
  3. Hodgson RJ1, O'Connor PJ, Hensor EM, Barron D, Robinson P.  Contrast-enhanced MRI of the subdeltoid, subacromial bursa in painful and painless rotator cuff tears. Br J Radiol. 2012 Nov;85(1019):1482-7. doi: 10.1259/bjr/45423226.
Written by Allan Phillips is a certified strength and conditioning specialist (CSCS) and owner of Pike Athletics. He is also an ASCA Level II coach and USA Triathlon coach. Allan is a co-author of the Troubleshooting System and was selected by Dr. Mullen as an assistant editor of the Swimming Science Research Review. He is currently pursuing a Doctorate in Physical Therapy at US Army-Baylor University.

Forgotten Aspect of Swimmer's Shoulder Prevention/Rehabilitation: Motor Control Training!

Take Home Points on the Forgotten Aspect of Swimmer's Shoulder Prevention/Rehabilitation: Motor Control Training!

  1. Overhead sports increase shoulder laxity and decrease motor control.
  2. Shoulder impingement decreases motor control of the shoulder.
  3. A complete shoulder injury prevention program must include motor control training.
Recently, I've been writing extensively for About.com about the shoulder injury rate in
swimming and the future injury rate. Overall, the exact prevalence of shoulder pain in swimmers was 3% in a study published in 1974 and has increased in recent publications: 42% in 1980 (Richardson 1980; Neer 1983), 68% in 1986 (McMaster 1987), 73% in 1993 (McMaster 1993), 40 – 60% in 1994 (Allegrucci 1994), 5 – 65% in 1996 (Bak 1996), 38% (Walker 2012). These rates in frequent surgeries for the swimmer's shoulder.

Even more disturbing is the prevalence of shoulder pain. Eighty-five percent of high school-aged swimmers reported mild shoulder pain in the past year, 61% reported moderate shoulder pain, and 21% reported severe shoulder pain. Of these, only 14% had been to a physician (Hibberd 2013). Also, 47% of these swimmers report using pain medication one or more times per week (Hibberd 2013). These unsafe and improper practices increase burnout, prevent swimming improvement, ending many swimmer's careers.

This results in many swimming programs performing elongated shoulder injury prevention
programs. Despite their best intentions, traditional shoulder prevention programs do not improve shoulder blade strength and control, termed motor control (Hibberd 2012). Even worse, many programs incorporate dangerous shoulder stretching programs which further increase instability at the shoulder, leading to worse shoulder motor control [consider mobility for swimmers, a more practical use of mobility training and static shoulder stretches].

I commonly refer to motor control as timing, a simpler way of understanding the importance of timing between various muscles at the joint. 

Shoulder impingement is thought to be the most common cause of shoulder pain in swimmers. There are several causes of shoulder impingement, one is poor motor control of the peri-scapular muscles. Overhead athletes undergo high levels of stress at their shoulder during maturation.  This high force is thought to cause microtrauma that over time causes adaptive changes which increase one's injury risk. One adaptive change is adapting the soft tissue around the shoulder, causing an increased range of motion which is thought to affect the shoulder motor control. However, as the motor control decreases, so does an athlete's ability to maintain correct biomechanics. Does high volume of overhead motions decrease motor control?

Motor Control in Healthy Overhead Athletes

Launder (2012) analyzed thirty collegiate baseball players (13 pitchers and 17 position players) without a history of shoulder injury for the past two year.

Shoulder motor control was tested on the throwing arm with the participant in the seated position with the shoulder and elbow flexed 90 degrees. Then, the shoulder was moved into 75 degrees external rotation, 30 degrees external rotation, or 30 degrees internal rotation. With the participant blindfolded, the shoulder was moved into one of these three positions, then the arm was held there for 10 seconds. After this, the arm was moved into a different position and then asked to return to the last position. The mean error for each position was measured.

The mean anterior shoulder deviation was 14.1 mm. There was no relationship between anterior glenohumeral laxity with 30 degrees internal an external rotation. However, there was a moderate association between anterior glenohumeral laxity with 75 degrees external rotation.

This study suggests as the amount of shoulder range of motion increases, the greater decrease in shoulder motor control. 

“This is most likely due to the increased tension placed on the static restraints and potentially increased activity of the mechanoreceptors at the higher range of shoulder external rotation (Launder 2012)”.

These findings suggest prevention programs should focus on improving motor control at the end-range of motion. However, it can not be concluded increased joint laxity causes altered joint proprioception.

In swimming, high amounts of shoulder range of motion are used for swimming success. Unlike baseball, swimming uses high amounts of shoulder internal rotation during the catch. This study showed 30 degree internal and external rotation did not find association with altered position sense, but did not assess full internal range of motion. However, this reviewer hypotheses large internal rotation results in similar motor control deficits. This suggests proprioception training at full range internal range of motion is required for prevention of injury of swimmers.

Motor Control and Shoulder Impingement

Worsley (2012) matched sixteen young adults with shoulder pain with 16 healthy controls. All those with shoulder pain were assessed for shoulder impingement manually and with ultrasound. Then, the group received motor control training where alignment, coordination, proper scapular orientation at rest, specific muscle (trapezius and serratus anterior), and manual therapy. The intervention was performed at home twice a day for 10 weeks, with 5 follow-up appointments.

Before and after the intervention scapular kinematics and surface electromyography of the shoulder muscles were assessed. Subjective questions of function were also provided before and after the intervention.

Before the intervention, the impingement group demonstrated  significant muscle delays in both the serratus anterior and lower trapezius. However, these muscles also had early termination during arm lowering in all planes. Imagine a swimmer having a delay of their muscles rotating the their shoulder for 1,500 strokes during a practice!

After the intervention, the subjective exam (shoulder pain and disability index, SPADI) improved significantly, on an average of 3.4 points [not a huge drop, but not bad for the intervention applied]. Also, post-intervention the delayed onset of muscle activation reduced significantly for these muscles.

This study further suggests improving motor control or muscle timing of the periscapular muscles for shoulder rehabilitation. 

Further studies the blinding of athletes is necessary, as well as a comparison intervention group, and more subjects. Moreover, the use of surface EMG increases the amount of cross-talk between muscles, further confirmation studies should utilize fine wire EMG. Unfortunately, until this research is performed all those seeking ideal shoulder injury prevention and rehabilitation should include shoulder motor control or timing exercises. I've been advocating these forms of exercises for swimmers for the past three years with limited acceptance in the shoulder prevention community. Let's change the course of shoulder injury in swimmers and start adding shoulder motor control training today! 

Check out this motor control exercise:

If looking for a complete shoulder injury prevention and rehabilitation program for swimmers including muscle length, strength, timing and improved biomechanics, check out the COR Swimmer's Shoulder System!

References:

  1. Worsley P, Warner M, Mottram S, Gadola S, Veeger HE, Hermens H, Morrissey D, Little P, Cooper C, Carr A, Stokes M. Motor control retraining exercises for shoulder impingement: effects on function, muscle activation, and biomechanics in young adults. J Shoulder Elbow Surg. 2012 Sep 1.
  2. Laudner KG, Meister K, Kajiyama S, Noel B. The Relationship Between Anterior Glenohumeral Laxity and Proprioception in Collegiate Baseball Players. Clin J Sport Med. 2012 Aug 14. [Epub ahead of print]
  3. Hibberd EE, Oyama S, Spang JT, Prentice W, Myers JB. Effect of a 6-week strengthening program on shoulder and scapular-stabilizer strength and scapular kinematics in division I collegiate swimmers. J Sport Rehabil. 2012 Aug;21(3):253-65. Epub 2012 Mar 2.
  4. Hibberd EE, Myers JB. Practice Habits and Attitudes and Behaviors Concerning Shoulder Pain in High School Competitive Club Swimmers. Clin J Sport Med. 2013 Sep 13. [Epub ahead of print]
  5. McMaster WC, Troup J. A survey of interfering shoulder pain in United States competitive swimmers. Am J Sports Med. 1993; 21:67-70.
  6. McFarland EG, Wasik M. Injuries in female collegiate swimmers due to swimming and cross training. Clin J Sport Med. 1996 Jul; 6(3):178-82.
  7. Muth S, Barbe MF, Lauer R, McClure PW. The effects of thoracic spine manipulation in subjects with signs of rotator cuff tendinopathy. J Orthop Sports Phys Ther. 2012 Dec;42(12):1005-16. doi: 10.2519/jospt.2012.4142. Epub 2012 Aug 17.
  8. Travell, J. Simons, D. Myofascial Pain and Dysfunction The Trigger Point Manual. Williams and Wilkins 1983.
  9. Tucker, Ross. "Training, Talent, 10000 Hours and the Genes."The Science of Sport. 11 Aug. 2011. Web. 08 Jan. 2012. .
  10. Weir PL, Leavitt, JL. Effects of model's skill level and model's knowledge of results on the performance of a dart throwing task. Human Movement Science. 1990 Sept; 9(3): 369-383.
  11. Wilk, KE, Reinold, MM, Andrews JR. The Athlete's Shoulder. Elsevier Health Sciences, 2008
  12. Kenal KA, Knapp LD. Rehabilitation of injuries in competitive swimmers. Sports Med. 1996 Nov;22(5):337-47. Review.
  13. McMaster WC, Roberts A, Stoddard T. A correlation between shoulder laxity and interfering pain in competitive swimmers. Am J Sports Med. 1998 Jan-Feb;26(1):83-6.
  14. Stocker D, Pink M, Jobe FW. Comparison of shoulder injury in collegiate- and master's-level swimmers.Clin J Sport Med. 1995;5(1):4-8.
  15. Ruwe PA, Pink M, Jobe FW, Perry J, Scovazzo ML. The normal and the painful shoulders during the breaststroke. Electromyographic and cinematographic analysis of twelve muscles.Am J Sports Med. 1994 Nov-Dec;22(6):789-96.
  16. Bak K. Nontraumatic glenohumeral instability and coracoacromial impingement in swimmers. Scand J Med Sci Sports 1996;6(3):132-144.
  17. Richardson AB, Jobe FW, Collins HR. The shoulder in competitive swimming. Am J Sports Med 1980;8(3):159-163.
  18. Neer CS, 2nd. Impingement lesions. Clin Orthop 1983(173):70-77.Allegrucci, Whitney SL, Irrgang JJ. Clinical implications of secondary impingement of the shoulder in freestyle swimmers. J Orthop Sports Phys Ther 1994:20(6):307-18.

By Dr. G. John Mullen received his Doctorate in Physical Therapy from the University of Southern California and a Bachelor of Science of Health from Purdue University where he swam collegiately. He is the owner of COR, Strength Coach Consultant, Creator of the Swimmer's Shoulder System, and chief editor of the Swimming Science Research Review.

Loaded Eccentric Training for Swimmer's Shoulder

Take Home Points on Loaded Eccentric Training for Swimmer's Shoulder

  1. Loaded eccentric shoulder training may improve shoulder strength.
  2. Loaded eccentric shoulder training does not improve function more than traditional shoulder impingement rehabilitation programs. 
Shoulderinjuries are the most common site of injury in swimming. Specifically, shoulder
impingement is the most common injury, commonly called swimmer's shoulder. However, two types of impingement exist, requiring further classification:

Shoulder external impingement (Subacromial Impingement)

This is the most common injury associated with a swimmer. In fact, the term “swimmer’s shoulder” is synonymous with shoulder impingement. However, in recent years the volume of external impingements in has decreased swimming is decreasing secondary to an increase in types of impingement (see below). External impingement is usually caused by an inflamed rotator cuff tendon (supraspinatus) that gets pinched while raising your arm overhead. The symptoms are noticeable during a “painful arc” of overhead motion of 60-130 degrees (for example, the recovery of freestyle). There are many causes for the rotator cuff to be pinched, most commonly irritation to a tendon is the cause. Often times, the area is irritated because the muscles around the shoulder are too tight, decreasing the area in the front of the shoulder and rotator cuff, thereby causing compression.

Shoulder internal impingement

Internal impingement involves the infraspinatus, a rotator cuff muscle located in the back of the shoulder. Repeated internal rotation (for example, the freestyle catch) can pull the labrum. The infraspinatus pulls on the labrum either due to tightness of the infraspinatus, weakness of the shoulder upward rotator muscles, or poor timing of the infraspinatus during stressful tasks causing irritation to the infraspinatus, labrum, or both.

Eccentric Exercise for Subacromial Impingement

Eccentric exercises have recently been found beneficial in tendon injuries, especially in the hip and ankle. Tendon degeneration occurs in subacromial impingement and heavy eccentric loading is believed to increase collagen production. Research of the shoulder with heavy eccentric exercises is lacking, but associations suggest that heavy eccentric exercise should improve shoulder impingement.

Maenhout et al. looked at sixty-one patients with subacromial impingement were randomly assigned to the traditional rotator cuff training (TT) or traditional rotator cuff training with heavy load eccentric training (ET). Isometric strength of abduction at 0, 45 and 90 of scapular abduction and internal/external rotation was measured. A questionnaire was used to measure shoulder pain and function. Outcomes were assessed at baseline, at 6 and 12 weeks after starting the intervention. The traditional rotator cuff training performed rotator cuff strengthening exercises 1x/day and the rotator cuff training and eccentric training group performed normal rotator cuff training 1x/day and heavy load eccentric exercise training 2x/day for 12 weeks with 9 physiotherapy treatments.

Results of Loaded Eccentric Training for Swimmer's Shoulder

Improvements in strength was greater in all directions in both groups, with the TT + ET group showed 15% higher gain in abduction strength at 90 degrees. Self-rated perception of improvement was similar in both groups.

Practical Implication of Loaded Eccentric Training for Swimmer's Shoulder

The improvement in strength is promising, but the mechanism of strength improvement was not physiologically analyzed. Also, the lack of self-reported function improvement is discouraging, as function is the the biggest factor in sports. Another problem with this study is the difference in training volume between groups. The extra volume in the TT + ET group could (and is likely) the reason for improvement.

For those with subacromial swimmer's shoulder, adding heavy eccentric exercises in
combination of traditional physical therapy rehabilitation may improve strength. Unfortunately, swimmer's commonly have secondary impingement our internal impingement of the infraspinatus, not the supraspinatus. Therefore, it is important to realize not all impingements are the same and subacromial impingement is unlikely for young swimmers. Also, remember biomechanics and other aspects of rehabilitation are as essential as improving strength. At COR, we provide a balanced approach of rehabilitation and return to swimming, ensure your rehabilitation program fits the bill. 

Reference

  1. Maenhout AG, Mahieu NN, De Muynck M, De Wilde LF, Cools AM. Does adding heavy load eccentric training to rehabilitation of patients with unilateral subacromial impingement result in better outcome? A randomized, clinical trial. Knee Surg Sports Traumatol Arthrosc. 2012 May 12.
Written by G. John Mullen received his Doctorate in Physical at University of Southern California (USC) and is a certified strength and conditioning specialist (CSCS). At USC, he was a clinical research assistant performing research on adolescent  diabetes, lung adaptations to swimming, and swimming biomechanics. G. John has been featured in Swimming World Magazine, Swimmer Magazine, and the International Society of Swim Coaches Journal. He is currently the owner of COR, providing Physical Therapy, Personal Training, and Swim Lessons to swimmers and athletes of all skills and ages. He is also the creator of the Swimmer's Shoulder SystemSwimming ScienceSwimming Science Research Review, and the Swimming Troubleshooting System.