ISCA Coach Education Program

We are thrilled that after about a year of production and development, the ISCA Education Program has officially launched!

The program is available online internationally and features evidence-based curriculum developed by sport scientists specifically for swim coaches. Our modern education portal is easy to navigate and secure, with transcript tracking and interactive course content.

ISCA Certification is available for coaches that are ISCA members and also complete the six core science-based courses (Biomechanics 101 & 102, Physiology 101 & 102, and Sport Psychology 101 & 102). The science behind swimming is something that all coaches need to understand to be effective and successful–and we look forward to providing this crucial piece of education to coaches around the world.

Get started today on the ISCA Education Portal: https://isca.courselaunch.com/

Learn more about ISCA Education: https://swimisca.org/education/

Get the details on ISCA Certification: https://swimisca.org/education/certification/

Demo an ISCA course: https://swimisca.org/courses/demo18/content/

4 Fundamental Shoulder Exercises for Swimmers

Fundamental shoulder strengthening exercises for competitive swimmers

Written by Behnam Liaghat, recognized specialist by the International Federation of Sports Physical Therapy, based in Denmark at the University of Southern Denmark. Email: bliaghat@health.sdu.dk

Following my recent blog about identifying joint hypermobility in swimmers, in this blog I will go through some of the top shoulder exercises for the competitive or elite swimmer to develop fundamental strength and neuromuscular control of the rotator cuff and scapular stabilizers.

In our recent research about young competitive swimmers with joint hypermobility (Liaghat et al., 2018), we found that swimmers with inherent shoulder joint hypermobility displayed reduced internal rotation strength and a tendency to poor activation of the scapular muscles. Another interesting finding was that swimmers with joint hypermobility not only display reduced absolute internal rotation strength, but these swimmers are weaker through the entire range of shoulder rotation. The suggested dry-land exercises in this blog can be designed to be beneficial for both hypermobile and non-hypermobile swimmers with few adjustments in range of motion, i.e. by increasing shoulder rotation to be as close as possible to the individual end range.

What are the benefits?

The four exercises specifically aim at improving shoulder retraction (refers to moving the scapula towards the spine), internal rotation and external rotations strength. To avoid injuries, it is important to target muscles on both sides of the shoulder to achieve a balanced intermuscular function. This is the rationale for including exercises for both internal and external rotation movements. Adequate strength in these movements has, besides injury prevention purposes, a positive effect on swimming stroke performance.

General guidelines

Some general guidelines for these exercises include performing them without producing any pain or discomfort and slowly through the entire range (approximately 6-8 seconds per repetition) to engage all important muscles. As there are no golden standard number of repetitions, you may want your swimmers to start with 3 x 30 seconds for the first 2-4 weeks and then move on to 3 x 8-12 repetitions with heavier resistance. Depending on the load applied and experienced level of muscle soreness, the exercises can be performed 3-5 times weekly. Make sure your swimmers breathe in a relaxed manner and engage the whole kinetic chain in all exercises.

When introducing these exercises to your swimmers, be certain that they can control the shoulder so excessive movement of the tip of the shoulder in either upward (towards the ear), backward or forward directions is avoided. In principle, reducing resistance and/or decreasing the range of movement may be applied to increase quality of shoulder control.

Fig. 1. Infraspinatus muscle on the posterior side of the scapula http://c1healthcentre.co.uk/one-of-our-top-5-reasons-you-have-arm-pain-infraspinatus-muscle-problems/

Active release of muscles before you start

Before instructing swimmers in performing these exercises, it is recommended to do some active release of the posterior rotator cuff muscles by standing against a wall with the arms perpendicular to the trunk and putting a pressure to the mid-point of the scapula with a lacrosse ball to target the infraspinatus area (Fig. 1). From here the swimmer can simply roll on the ball and add a shoulder external and internal rotation movement for up to two minutes to release tight and sore muscles (Fig. 2 A-C). The active self-release can be performed in supine for adding more pressure.

Fig. 2 A-C. The Danish swimmer Matilde Lerche Schrøder showing an active release of the posterior rotator cuff muscles.

Now let us move on to the top dry-land exercises for fundamental shoulder strength

 

Exercise 1: Prone 1-arm diagonal lift

Either lie on the floor or on a gym ball supporting with your feet and one arm. Apply resistance with an elastic band. Slightly retract and depress your shoulder before lifting your arm with a 45 degrees angle away from the trunk´s midline. While lifting the arm, a maximum external rotation is performed in the arm so the thumb points towards the ceiling.

Level down by lifting the arm perpendicular to the trunk’s midline.

Level up by adding a back extension in the movement or lifting the opposite leg.

 

Exercise 2: Supine internal rotation 1

Either lie on the floor or on a gym ball supporting with your feet. Apply resistance with an elastic band. Slightly retract and depress your shoulder before turning one arm at a time internally as far as possible without losing shoulder control (e.g. protracting the shoulder towards the ceiling).

Level up by adding oscillation (fast movements back and forth) through the movement.

 

Exercise 3: Supine internal rotation 2

Description: Either lie on the floor or on a gym ball supporting with your feet. Apply resistance with dumbbells. Slightly retract and depress your shoulder before slowly turning one arm at a time externally in cranial direction and then back to vertical position in the underarm without losing shoulder control (e.g. avoid pushing the shoulder towards the ceiling).

Level up by adding more load and increasing range of external rotation.

 

Exercise 4: Prone external rotation

Lie on a gym ball supporting with your feet and one arm. Apply resistance with a dumbbell. Slightly retract and depress your shoulder before externally rotation your arm with the upper arm perpendicular to the trunk.

Level up by adding more load and increasing range of external rotation.

 

Every swimming coach should be familiar with these top shoulder exercises and include them in some content as part of the dry-land routines for injury prevention and for enhancing swimming stroke performance.

 

A special thanks to the Danish swimmers Matilde Lerche Schrøder and Line Virkelyst Johansen for giving their photo consents.

Resource:

Liaghat, B., Juul-Kristensen, B., Frydendal, T., Marie Larsen, C., Søgaard, K., & Ilkka Tapio Salo, A. (2018). Competitive swimmers with hypermobility have strength and fatigue deficits in shoulder medial rotation. Journal of Electromyography & Kinesiology, 39, 1-7. DOI: 10.1016/j.jelekin.2018.01.003

Download link: https://authors.elsevier.com/a/1WU8g3kurobLDS

How to Analyze Breaststroke Swimming

As a take home message:
1. In this piece we did the analysis of three age-group breaststrokers.
2. Modeled data sometimes does not fit completely the individual data of a specific swimmer.
3. After benchmarking the swimmers against data retrieved from the literature we have learned that one of the swimmers is able to reach a high speed (strong point), but with a high speed fluctuation (main concern).
4. Several analyses were carried out to run a full diagnosis, prescribe what to change and predict the outcome of such improvements. He would be able to increase the speed by 0.1 m/s (faster) and decrease the speed fluctuation by 10% (more efficient).

In my latest piece eventually I shared a picture that depicts modeled and real data. At that time, it was explained that most textbooks and even research papers share modeled data because: (i) it will be easier to understand a concept having “smoothed” data and; (ii) the modeled curve aims to represent the main trend across all subjects assessed.

Unfortunately, there is a huge drawback of this. Most of the times the theoretical model does not fit in the data of one particular subject. In academia, this falls under the topic “universal versus individual data analysis” (Barbosa et al., 2010). I.e., data from a pooled sample of swimmers does not represent what is the best for my swimmer. Indeed, the inter-individual variability is a concern for several researchers (Seifert et al., 2011).

A very good example is the assessment of the speed fluctuation. The academic jargon for speed fluctuation is “intra-cyclic variation of the velocity”. Meaning, it is how speed changes over one fig1single stroke cycle. As you are aware the swim speed is the result of the balance between thrust (propulsion) and resistance (drag). So, over one single stroke cycle the speed goes up whenever the thrust is higher than the resistance. The speed goes down if the thrust is lower than the resistance.

Let’s apply these two concepts (universal v. individual analysis; assessment of the speed fluctuation) to breaststroke. Figure 1 (top panel) depicts what would be the typical speed fluctuation at breaststroke reported in a textbook. At the begging of the stroke cycle the speed goes up due to the kicking and eventually reaches a first peak (thrust by the kick is higher than the water resistance). After the kick the swimmer will glide in the streamlined position. Because there is no thrust, only passive drag is acting upon the body, the speed decreases and we can find that “valley”. After the glide it is performed the arms’ stroke and the speed increases once again (second peak). With the legs’ recovery the resistance increases significantly and speed goes south sharply.

Now, that we did the re-cap of the stroke cycle at breaststroke, I must share with you that this curve is the modeled data of three age-group breaststrokers. Figure 1 (bottom panel) depicts the variations in the modelled curve considering the individual differences among the three swimmers. For instance, at the beginning of the stroke cycle (the first upward slope, i.e., kicking) the vertical lines are rather small. That means that the three swimmers are quite similar, little difference can be found among them. But, the vertical lines on the second peak are big. So, it seems that the three are doing thing in a different way at this phase of the stroke cycle.

So far, we did the analysis of the pooled and modeled data of three swimmers (i.e. universal analysis). Moving on to the individual analysis. Figure 2 depicts the individual curves of each subject. One seems to be a top-tier age-group breaststroker (blue line), the other two a mid- and a low-tier swimmers (red and green lines, respectively). Now, you understand why I told you at the beginning that unfortunately the modeled curves most of the times do not fit the individual curves. Figure 1 was computed based on the data of these three swimmers represented in Figure 2. We can see that at the beginning the curves of the three match almost perfectly, but then start to drift away from each other. This is why the variation is low at the beginning of the cycle and high at the end as shared earlier (vertical lines, i.e. standard deviation, in figure 1 – bottom panel).

 

fig2

Now, we are ready to do the quantitative analysis. For the kinematic analysis, I selected the average swimming velocity (v), stroke frequency (SF), stroke length (SL), maximal velocity (v-max) and minimal velocity (v-min) within the stroke cycle. Two other variables were selected as efficiency estimators, and this includes the stroke index (Costill et al., 1985) and the speed fluctuation (e.g., Barbosa et al., 2005).

Based on the average speed over the cycle it is easy to follow that we are assessing swimmers of different competitive levels. The green swimmer has a lower speed, SF, SL, dv and v-max. What makes the difference between the blue and red swimmers? The SF is slightly higher, but the SL shorter for the later breaststroker. The red swimmer has a lower speed fluctuation than the blue counterpart. So, this deserves some further investigation.

table1

First things first, we should benchmark the swimmers against other subjects in our database or data retrieved from the literature. Today I will benchmark the swimmer against the data reported in a research paper (Barbosa et al., 2013). The black dots are the data reported in the paper, the coloured dots are our swimmers. We are benchmarking the relationship between speed fluctuation and swim velocity. Now, we are sure that the green swimmer is an average breaststroker, the red a mid-tier-almost-top-tier and the blue a top-performer. The main concern is that the blue swimmer despite reaching a high speed also shows a big speed fluctuation in comparison with two other counterparts that race at similar paces (1.2-1.3 m/s, black dots). These two reach the same speed with speed fluctuations lower than 40% though. Being the bigger picture, now we should do the analysis of the individual curve of the blue swimmer.

fig3

The top-left panel (figure 4) depicts the kick. The blue swimmer is the one reaching the highest speed (2.01m/s). The rate of speed development is the same for the three, but the kicking action is 0.03s longer for the blue swimmer (the kick took 0.28s). So, one might say that the kick power (or mechanical impulse) is quite nice for the three, the main difference might be in the legs’ insweep. This is the end of the kick, when the swimmer squeezes up the water between the calf and feet, the plantar surface almost touches each other and toes point backwards-inwards.fig4

The top-right panel (figure 4) is related to the glide. This seems to be a major drawback for the blue swimmer. The speed drops 0.99m/s in 0.32s. Probably the glide is a little bit too long and the body position not the best. For instance, the red swimmer does not have such a significant decrease in speed. One should have arms fully extended and horizontal, head in a neutral position between the upper-arms and looking downward-forward, hips high close to the surface, legs fully extended and horizontal with no sinking of the feet.

The bottom-left panel (figure 4) reports the arms’ action. That took 0.26s and he reached a maximal speed of 2.09m/s. The blue swimmer is very balanced because the ratio between the maximal speed reached by kick and arms is 2.01 v. 2.09m/s. Several breaststrokers are more kick-driven and neglect the arms’ stroke. Both the red and green swimmers are not able to reach the same speed over the arms’ stroke they did at the kicking. I.e., the second peak (arms) is smaller than the first (kick). If they improve the arms’ action, the average speed would increase even though at the cost of the efficiency (i.e. probably speed fluctuation would increase). With that, they would reach the performance level of the blue swimmer. After reaching such level, would be time to think about the speed fluctuation (which is what we are doing right now to the blue swimmer).

The bottom-right panel (figure 4) help us to have a deeper understanding of the legs’ recovery, when the knees and hips bend. This should be another concern for the blue swimmer. In 0.34s he loses 1.83m/s reaching the lowest speed (0.25m/s). I.e., for tenths of a second he almost stopped in the water. Avoid dropping the thighs. Less bend by the hip and keep the knees high. The end of the arms’ insweep and legs’ recovery happens at the same time. Head moves as one with the torso (spine completely aligned). Do not bend or extend the neck. This phase is all about tempo and sync between upper and lower limbs.

An analyst must be able to answer a few questions:

  1. What is happening?
  2. What can we do to improve?
  3. How much will be the improvement?

Well, the diagnosis is done. So we can try to help the blue swimmer to be one of the finest breaststrokers.

Time to re-cap what we’ve learned so far: his propulsion is very good. Let’s keep this good work. The resistance after the glide and legs’ recovery are two concerns and deserve special attention.

Good coaches will suggest a set of drills in order to improve the gliding position, the tempo (notably the duration of the glide), the thigh and shank positions over the legs’ recovery and timing between arms and legs. Follow the link for a comprehensive list of drills (WARNING: the original paper is in Portuguese. Sorry for the inconvenience. If you speak a Latin language it is easy to understand. Alternatively I have a nerdy solution for you: 1. Install the “google translate” in your smartphone or tablet; 2. Set the app to translate from Portuguese to English; 3. Below the field to type the word to be translated you will find the camera icon. Press that icon/button. 4. Point the camera to the text and the app will automatically translate the text for you. 5. To clarify: you need a hardcopy of the piece or softcopy being displayed in a second device. E.g., display the piece on a laptop and use the phone for the automatic and real-time translation).

A good analyst will try to predict what happens with the changes advised. He will have to work the math, do some modelling, signal processing, chunk the numbers and provide a result. My prediction for the blue swimmer is as follows. If over the legs’ recovery the speed does not decrease up to 0.25m/s but 0.33m/s, the speed fluctuation improves to 36.03% and the speed to 1.36m/s (i.e. 0.1m/s faster). Figure 5 includes the real glide (blue line) and the “optimal” glide (magenta line). If the swimmer improves his glide, the speed fluctuation reduces to 35.29% and the speed to the same 1.36m/s.

So, if the swimmer and the coach embark in only one of these two solutions, the dv-v will be 35%-1.36m/s. End of the day, shifting the blue dot in the figure 3 to the coordinates (35; 1.36) one can learn that the swimmer not only becomes the fastest but also the most efficient.

fig5

References
1. Barbosa TM, Keskinen KL, Fernandes RJ, Colaço C, Lima AB, Vilas-Boas JP. (2005). Energy cost and intra-cyclic variations of the velocity of the centre of mass in butterfly stroke. Eur J Appl Physiol. 93: 519-523.
2. Barbosa TM, Morouço P, Jesus S, Feitosa W, Costa MJ, Marinho DA, Silva AJ, Garrido ND (2013). Interaction between speed fluctuation and swimming velocity in young competitive swimmers. Int J Sports Med. 34(2): 123-130
3. Costill D, Kovaleski J, Porter D, Fielding R, King D (1985). Energy expenditure during front crawl swimming: predicting success in middle-distance events. Int J Sports Med. 6: 266-270
4. Seifert L, Leblanc H, Herault R, Komar J, Button C, Chollet D. (2011). Inter-individual variability in the upper-lower limb breaststroke coordination (2011). Hum Mov Sci 3:550-65

By Tiago M. Barbosa PhD degree recipient in Sport Sciences and faculty at the Nanyang Technological University, Singapore

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