Should Coaches Change Asymmetries in Swimmers: Part III

Take Home Points on Should Coaches Change Asymmetries in Swimmers: Part III
  1. An appearance of asymmetry does not automatically imply asymmetry of function
  2. Asymmetrical strokes may be related to physical characteristics and physiological capacity
  3. Working with an asymmetrical stroke is a mix of science and art
In previous posts we have reviewed literature on swimming and asymmetries (Part I, Part II). This installment will integrate information recently published by Dr. Formosa, summarized in his interview. What seems like a simple issue can get very complex when we look at all the factors involved. Many kids have had their strokes changed simply because a coach did not like how the stroke looked. Now, I’m not suggesting that kids should be allowed to swim without correction, but rather that correction must rely on more than “it looks bad.” 

Before getting to the interview, recall from a prior post in this series that, "Despite attempts to impose ideal symmetry, a perfectly symmetrical stroke and body are both unrealistic. We all have favored brain hemispheres, eye, ear and limb preferences along with structural differences in how our organs sit within our bodies. Asymmetry may also follow us into the water. But there is still good reason to make swimmers “less asymmetrical” even perfect symmetry is a fiction."

Nearly every swimmer brings asymmetries to the water. This isn’t necessarily a bad thing; just something to be accounted for when dealing with technique. A key point from the literature is that we can’t fully determine functional symmetry without measuring force. Yet surely there are ways to estimate whether someone is symmetrical or not, which leads us to Dr. Formosa’s work. 

As Dr. Formosa summarized, 

"The front crawl and backstroke research papers highlight that although an athlete may present with a similar timing from hand entry to hand exit the force profile that they are producing through the water is variable. Therefore, it should not be assumed that if a swimmer presents with a symmetrical timing pattern their force profile is also symmetrical. 

Further, elite athletes that apply force in water based sports such as rowing and kayaking have the ability to subtly manipulate their stroke to optimise force production. The complexity of symmetry is evident with the findings that although athletes demonstrated symmetrical timing their net drag force values were asymmetrical." (Formosa 2011, 2012, 2013)

Practical Application

While better swimmers often deliver force symmetrically, HOW they accomplish via individual can vary greatly and requires a more critical thought process than simply how the swimmer looks. The practical implication here is that coaches must consider all the information. 

We have written previously about movement screening to learn more about swimmers’ individual qualities. Not everyone has access to high tech underwater force measurement devices, but knowing your swimmer’s physical baseline is valuable. Some swimmers move their arms asymmetrically in 2D video but ultimately produce power with symmetry. 

Breathing patterns are also key factors, as preferred breathing style may lead swimmers to gravitate toward an asymmetrical looking stroke. Prior injury may also lead swimmers to develop protective patterns around injury. Yet thanks to the amazing plasticity of the brain, talented athletes can learn to develop force symmetrically despite lasting mechanical limitations. The extent to which this actually happens has yet to be studied but is a possible line of inquiry for future research as the foundation of the current literature on asymmetries expands. 


  1. Formosa, D. P., Mason, B., & Burkett, B. (2011). The force-time profile of elite front crawl swimmers. Journal of Sports Sciences, 29 (8), 811-819.
  2. Formosa, D. P., Sayers, M., & Burkett, B (2012). Front-crawl stroke-coordination and symmetry: A comparison between timing and net drag force protocols. Journal of Sports Sciences, 31 (7), 759 – 66.
  3. Formosa, D. P., Sayers, M., & Burkett, B. Symmetry of elite backstroke swimmers utilising an instantaneous force profile. Journal of Sports Sciences, Accepted 5th July 2013.
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.

Early Diversification for Swimmers

Take Home Points for Early Diversification for Swimmers
  1. When to begin specialization is an individualized process.
  2. Some elite performers benefit from early specialization, but it may not be best for the majority.
  3. Weighing the risk of early specialization is mandatory for determining time for specialization.
Sports specialization is defined as intense, year-round training in a single sport with the exclusion of other sports. Sports specialization is occurring earlier than ever before. Previous surveys found parents were the main motivator to initiate a sport, where coaches were the main reason behind specialization. I discussed this topic in detail with much backlash on Swimming World, overall suggesting a two-month break rule. Once again, this is not a system for everyone, at every point in their career, instead a rough suggestion for youth athletes. Nonetheless, the idea of early sports specialization exist and become more pronounced with Michael Phelps succeeds with early specialization. However, sometimes considering trends in other sports questions the current state of our own sport. Other times, and admittedly most often, it bears minor help on the sport of swimming.

Jayanthia (2012) looked at sports specialization in tennis players. Rates of sports specialization appear to increase with age. A study of 519 US Tennis Association junior tennis players found that 70% began specializing at an average age of 10.4 years old. Specialization rate gradually increased after 14 years, with 95% of players having specialized by age 18 years. However, enjoyment and satisfaction ratings decreased in players older than 14 years old. 

Musicians have been believed to improve from early specialization. However, the rates of success with sporting specialization are unclear, despite frequent expert opinions. A few studies have actually suggested elite success inversely correlated with training volume at the age of 14.

Early diversification often leads to more success and is suggested to provide an: “athlete with valuable physical, cognitive, and psychosocial environments and promotes motivation (Jayanthia 2012).”

As it seems, the benefits of early specialization are uncertain, but the risks appear consistent: more burnout, less enjoyment, more injuries

Some degree of sports specialization is necessary for elite success, however it seems imperative to delay early intense specialization for long-term enjoyment, health, and success for the majority of athletes. 

Practical Implication

Early exposure is likely necessary for the creation of ultra-elite swimmers, yet early specialization increases the likelihood of early burnout and quitting. For this reason, it is essential to start children early in swimming, but encouraging them to participate in other sports and activities until their post-pubescent years.

Each child should have the opportunity for elite performance, unfortunately this situation is too often rushed. As Dr. Sokolovas notes, "females need about 9 to 10 years of year round training, while males need 10 to 11 years.” This results in many parents, coaches, swimmers, pushing their kid at the age of 4 to swim year round, peaking at 14 or 15. 

Why rush?

Sure there are unfortunate reasons, like swimming status, but this isn’t needed. Instead
of looking at the amount of time for elite swimming success as in years, many think about it in hours, but remember, there are a lot of ways to get hours in swimming (12 years of swimming, 20 hours a week, for 10 months a year equals 10,080 hours for example). Unfortunately, newer research is suggesting the time equation or 10,000 hour rule is over simplified. Instead, quality of training, physical capacities, and many other factors are involved as well as training hours.

Even Dr. Sokolovas says “year-round” training is training 48-50 weeks a year, I just argue this can be extended and potentially stretched out for longer athletic development. Perhaps swimmers should doubles 3 days in a row, then a day off for an entire season! Maybe this scenario would provide the recovery needed for long term success and enjoyment.

No matter what training frequency and break scheduled is considered, make sure it receives thorough investigation, as the plan a 10-year-old performs influences their enjoyment and health, not only for sport, but also exercise. If the swimming community is disrupting swimmer's long-term health by increasing the injury risk and enjoyment of exercise, then the current status quo requires reconsideration. Ask this, as well as:
  • Are swimmers getting faster are more swimmers getting faster earlier in their career? 
  • Are there more elite swimmers or just more fast swimmers? 
With data and research, these are simple questions, but difficult answers. Nonetheless, the should guide future plans for long-term success and emphasis on early diversification/specialization for swimmers.


  1. Jayanthia, N, Pinkham, C, Dugas, L, Patrick, B, LaBella, C. Sports Specialization in Young Athletes Evidence-Based Recommendations. Sports Health: A Multidisciplinary Approach October 25, 2012. 1941738112464626.
  2. Sokolovas G. Why Swimmers Need to Train Year Round
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.

Base Training for Swimming

Take Home Points on Base Training for Swimming:
  1. Different approaches exist for base training
  2. Traditional approaches have focused on building an aerobic base through
  3. Base training should be more individualized than uniform application of high yardage to an entire squad
As swimmers transition from summer training to fall training, many programs move from a
competition focus to base focus.  The term base training is often discussed but often has varied interpretations on the pool deck.  Traditionally, base training has marked a return to less intense and more aerobically based swim training after a summer of racing.  Though some would describe base replenishing the aerobic system after a period of shorter distance focus, optimal dosage is less clear, particularly in determining transfer to shorter events.

One of the most referenced studies in swimming (Costill 1991) found that adding a period of two-a-days for increased mileage in the early portion of a training cycle did not lead to significant short term improvements, but did result in significant improvement after a late season taper.  Was it the traditional base training that led to improvement or some other factors?  Wakayohsi (1993) found that six months of aerobic base training improved 4 x 400m swim test velocity, but its unclear if this training would have effectively transferred to shorter distance racing.  (additionally, this study was only eight male swimmers with no control group).  

Care must also be taken to accommodate swimmers entering base from different starting points.  On a single team you can have swimmers who competed all summer in national and international meets, those who did consistent but not intense training, those who cross trained, and those who barely did anything.  Each type of swimmer will require a different approach, no matter how emotionally invested a coach is in his/her one-size-fits-all program (and no matter how much they want to punish the lazy swimmers who didn’t train during the summer).   This is a key but often overlooked point of base. 

'The longer and more substantial is this basic form of training, the better and longer an athlete will be able to hold a peak performance capability when serious competitions occur. The corollary to this statement is: an athlete's ability to hold a peak performance status is directly proportional to the amount of base (preparatory or background) training that is done." (Rushall 1994)

Now, while most would agree with this statement, the HOW is less clear.  Some interpret this to mean base training should include record setting yardage with ample doses of 400-1000yd repeats.  Others may interpret “longer and substantial” to mean never take a break.  In truth, the varying interpretations of base training reflect the nature of base training as being grounded in as much art as science.  True, it’s possible to measure baseline fitness through time trials, lactate, VO2max, etc but deciding how to improve those parameters and what to do with that information is less well established. 


Though many definitions of base exist, we should all agree that base is about preparing for the next phase of training.  Base can also be seen as having dual purposes, from preparing for future competitions while actively recovering from prior hard training.  This may also support the idea of planned time off in which swimmers focus on non-swimming activities.  

“The basic preparatory phase can include activities drawn from sports which are related to swimming. This phase of training would also include the greatest amount of auxiliary training.  However, because such activities are beneficial for establishing a physiological base, does not mean that they are just as beneficial when highly specialized training is employed. At that time they have the potential to disrupt refined neuromuscular patterns associated with skill.” (Rushall 1994)

Ultimately, base should be seen as simply that: a base.  Determine what the athlete needs for late season success and build the foundation from the base phase.  


  1. Wakayoshi K1, Yoshida TIkuta YMutoh YMiyashita M.  Adaptations to six months of aerobic swim training. Changes in velocity, stroke rate, stroke length and blood lactate.   Int J Sports Med. 1993 Oct;14(7):368-72.
  2. Costill DL1, Thomas RRobergs RAPascoe DLambert CBarr SFink WJ.  Adaptations to swimming training: influence of training volume.  Med Sci Sports Exerc. 1991 Mar;23(3):371-7.
  3. Dr. Brent Rushall.  ANNUAL PLANNING FOR SWIMMING FITNESS.  Adapted from NSWIMMING COACHING SCIENCE BULLETIN: Volume 2 Number 6 - July-August, 1994.
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.

Friday Interview: Liz Sanil Discusses Motor Learning

1) Please introduce yourself to the readers (how you started in the profession,
education, credentials, experience etc.).
I first became interested in kinesiology after a visit to an athletic therapist following a high school wrestling injury. During my undergraduate degree I became particularly interested in motor learning and control. My MSc, Ph.D. and postdoctoral research have focused on practice factors such as practice scheduling and feedback and providing choice to the learner during practice.

2) You have published many articles on motor learning. What are the different theories on motor learning?
Theory plays a large role in my research projects. The predominant formal theory in motor leaning today is Schmidt's schema theory, which addresses movement production and evaluation. This theory borrowed the effective parts of earlier motor learning and psychology theories and built upon them with knowledge about motor control and leaning processes. Schmidt's Schema theory does not however provide us with a complete understanding of motor learning and there are other important theoretical perspectives and hypotheses which can contribute to our understanding of motor learning.  Schmidt and Lee (2011, chapter 13) divide these perspectives into categories including the cognitive perspective which addresses the role of cognitive processes such as planning and evaluation of movement in motor leaning, the hierarchical control perspective which addresses the construction of motor programs, shifting control of a skill from higher to lower-level control processes, and the Bernstein perspective which addresses stages of learning though which degrees of freedom (e.g. joints) are progressively released and reorganized. This perspective also emphasizes the interaction between the sensory-motor system and the environment. Recently, some aspects of motor learning have also been examined from motivational perspectives originating in psychology theory.

3) What is the motor learning research confident about?
Much of the application of motor learning research is dependent upon factors such as the type of task to be learned, the characteristics of the learner (such as age or experience level) and the type of environment in which the skill is learned and performed. New theoretical perspectives and hypotheses are also being examined in attempts to address the shortfalls of current theories. Nonetheless, there are several general concepts we can be reasonably confident about that are applicable to coaching. One very  straightforward concept is termed "law of practice", which states that with all other things being equal, the more practice trials completed, the more learning will occur. Improvements are generally large at the start of practice and decrease in magnitude over time (Schmidt & Lee, 2011, chapter 11). Another example is the concept of stages of learning; several researchers have proposed that learners move through a series of stages in the learning of a motor skill.  While the number of stages and their specific names differ between researchers, it is generally agreed that at the start of practicing a new skill, learners engage in a lot of cognitive activity figuring out appropriate strategies. At this early stage performance is quite variable and many training techniques are most effective, aiding in the development of appropriate strategies. In the next stage learners have already figured out what it is they need to do and now focus more on adjustments to how the skill is performed. In this stage the movements become more consistent and effective through relatively small changes. After quite some time of practice the skill may become relatively automatic, freeing up resources for the learner to use on other tasks (Schmidt & Lee, 2011, chapter 13). Understanding approximately where a particular learner or athlete is in terms of these stages of learning can help a coach choose appropriate training techniques to benefit learning.

The research provides consistent evidence for the effectiveness of many training techniques in relation to factors such as practice scheduling, feedback, focus of attention, models, guidance and part versus whole practice, but in interest of space I won't go into great detail here (See chapters 11 & 12 in Schmidt & Lee, 2011).

4) What are some big unknowns or misconceptions?
Perhaps one of the biggest misconceptions about motorlearning, particularly in sport, is
that performance during practice is indicative of learning that has taken place. Because motor learning is considered a relatively permanent change in performance, due to practice, sometimes the changes that are taking place with learning are not immediately evident. Many strategies that have been shown to benefit learning can be detrimental to performance during a practice session. Dr. Damian Farrow gives a great example of this distinction using an example of swimming training sessions (see pages 372-375 in Skill Acquisition in Sport: Research, Theory and Practice, Hodges, N.J. & Williams A.M. eds.) He distinguishes between performance-based practice sessions and learning-focused practice sessions. Performance-based sessions have a focus on performance outcome measures (e.g. time, stoke rate) and the inclusion of all elements of a race environment (e.g. starting with a dive rather than at the edge of the pool), while learning-focused sessions focus on technical skill production, sometimes including trial and error, with much less emphasis on outcome measures. Even though swimmers may indeed be learning and improving technique during the learning-focused sessions, the changes may not be evident until a later performance -based session.

Another misconception is that learners (athletes) are good at predicting how well they have learned a skill. As discussed above, some training strategies may lead to poorer performance during a practice session even though significant learning has occurred. Conversely, a practice session during which an athlete has shown very good performance, may have resulted in relatively little learning. Often learners who have performed well during a practice session using a less effective training strategy for learning will over-estimate how much they have learned, while those who produced poorer performance using a more effective strategy will under-estimate how much they have learned (e.g. Simon & Bjork, 2001.)

5) What aspects of motor learning should coaches, particularly swim coaches use?
There are several training strategies, in particular, practice organization, instruction and feedback strategies with evidence from motor learning research, that are helpful for coaches. Distinguishing between performance and learning as discussed above is one aspect  of practice that should be considered by coaches. In general, coaches should also consider variety in practice schedules when deciding upon drills for a particular practice session. A simple application of this would be to space out the practice of a particular skill (e.g. flip-turn) throughout the practice rather than completing several in a row at the beginning of practice. Another consideration for coaches is that too much feedback from external sources, such as a coach, can produce a dependency on that feedback. One way to guard against this dependency is to ask swimmers how they felt they performed before providing feedback. Another way would be to withhold feedback from certain trials or delay the feedback provision until several trials have been performed. Dr. Farrow gives specific examples of changes he has suggested for typical swimming training sessions in the past. (see pages 372-375 in Skill Acquisition in Sport: Research, Theory and Practice, Hodges, N.J. & Williams A.M. eds.)

6) What were the practical implications for coaches and swimmers from your study?
One important thing to note is that our study used what we call a discrete skill (a skill with a definite beginning and end) while the majority of swimming would be considered a continuous skill (a skill with no inherent beginning and end). With this in mind, this study would be most applicable to aspects of swimming such as a dive or flip turn. However, please keep in mind that these swimming-specific skills are more complex and difficult than the simple crokinole-type skill used in our study. In our study one group started with the easiest version of a task and progressed through more difficult versions throughout practice. The other group began with the most difficult version and progressed through easier versions. In most sport situations where an athlete is learning a new skill, the schedule of the first group (easy-to-difficult progression) is the one followed. In our study the second group (difficult-to-easy progression) performed better during practice and on a transfer test. A transfer test measures how well a learner (or athlete) is able to adapt what has been practiced to a new version of a task. In swimming the need for this type of adaptation may arise when an athlete encounters an unfamiliar starting block, or begins a turn from a less-than-ideal location. In our study, the second group started practice with a large amount of error and decreased the amount of error throughout practice as the versions of the task got easier and as the learners gained more experience. This suggests that for some tasks (such as our relatively easy discrete task) error at the start of practice isn't necessarily a bad thing. In fact, we suggest that the challenge of a more difficult task at the right time during practice may be what benefits the learner on later transfer tests. In terms of practical implications for coaches, of course, with the safety of the athlete kept in mind, a coach might consider that errors at the beginning of practice are not necessarily detrimental to learning in the long run and may help with adaptation to new situations. Some factors to consider when designing practice schedules are the difficulty of the task itself, the experience of the learner and how important adaptation of the skill is. With further studies examining the role of errors at the beginning of practice for more difficult and/or continuous tasks, more specific recommendations applicable to swimming may come forth.

7) What is the future of motor learning and sports?
Motor learning researchers and coaches have much to offer each other. For example, coaches can help researchers understand the applied nature of skill-learning for his or her sport, while researchers can provide new evidence-based training strategies for coaches to consider. Skill acquisition specialists, knowledgeable about motor learning are currently working together with high-performance sport organizations (e.g. in Australia and New Zealand) to impact the performance of elite athletes.

8) What research projects are you currently working on or should we look from you in the future?
Plans for my future research program focus on practice variables such as scheduling and feedback and taking a look at the wider picture of the practice context as a whole. This work will be based in motor learning and control theory as well as sport and exercise psychology theory.

References and relevant reading
Schmidt, R. A., & Lee T.D. (2011) Motor Control and Learning a Behavioral Emphasis (5th ed.) Champaign, IL, Human Kinetics.
Hodges, N. J. & Williams, A.M. (Eds.).(2012). Skill Acquisition in Sport Research, Theory and Practice (2nd ed.) New York, NY, Routledge.
Simon, D.A., & Bjork, R.A. (2001) Metacognition in Motor Learning. Journal of Experimental Psychology: Learning, Memory, and Cognition, 27, 907-912.
Farrow, D., Baker, J., & MacMahon, C. (Eds.).(2013). Developing Sport Expertise Researchers and Coaches put Theory into Practice (2nd ed.) New York, NY, Routledge.

Adjusting to College Swimming

Take Home Points on Adjusting to College Swimming

    1. Managing stressors outside the pool is critical for an effective transition between age group and college swimming 
    2. Communication is key as swimmers adapt to new training programs 
    3. Sleep and nutrition are two areas that are common downfalls for swimmers making the transition to college
    The new school year marks a transition for swimmers across the country. An entire
    freshman class is not far from making their college swimming debuts. In this post, we’ll explore key issues in the transition from age group to college swimming.

    Sleep: Sleep has been a major topic on this site. (Sleep Restriction Impairs Performance, Does Extra Sleep Enhance Performance) Though early mornings are not unique to college, swimmers often walk a finer line with an adjustment to college life. The predictable rhythm of days filled with high school class and parental monitoring can give way to varied class schedules and curfew-less nightlife. Sleep also had recent attention in an NCAA report finding that swimmers had the highest use of sleep aids among college athletes. (Swimmers Biggest Users of Sleep Aids in NCAA

    Nutrition: Many programs have resources beyond what is offered in high school (athletic department nutritionists and athlete dining), but as with sleep, the onus is still largely on the swimmer to make good choices independently. (see Swimming Nutritional Program, Peri Workout Nutrition, Dr. Mougios interview, Dr. Rosenbloom interview, Dr Carvalho interview) In the same report cited above, college swimmers (especially females) were shown to have among the highest uses of nutritional supplements compared to other college athletes. 

    Training: Generally, swimmers will choose a program that is compatible with how their bodies historically respond to training. Kids with high yardage, lower intensity backgrounds will be more drawn to similar college programs. Likewise, kids with high intensity backgrounds may favor similar training at the college level. Still, despite recruiting overtures, not every match is perfect, leading some swimmers requiring more time for adjustment in the pool. Communication is key, as some coaches believe their "one-size-fits-all" program is beyond reproach, meaning that any poor performance is the swimmers fault in their eyes! 

    Little fish, big pond. For kids coming from nationally recognized clubs and who have major national and international meet experience, this is less of a shock having been in the water regularly with swimmers better than them. But for those in smaller programs and with more fragile mindsets, it can be a shock. Now, this reaction is perfectly normal and many swimmers do get more comfortable. Unfortunately though, many do not and fail to meet expectations. It is critical to see being surrounded by faster swimmers as an opportunity for growth, not a blow to the ego! 

    Travel: again, probably less adjustment for kids with national and international experience, but the frequency of out of state travel can be a new stressor, even for kids who have international experience. Finding yourself constantly on a bus or plane with school assignments looming is a different type of stress than big international trips during summer vacation. The frequent travel can also compound with other responsibilities, leading to…

    Academics, Social: It might seem odd to lump these two areas together, but both share the common theme of being non-swimming factors with the potential to heavily impact swimming. As with other factors, these too will depend on how the swimmer chooses to react to his/her new environment. History has shown that many swimmers can strike an effective balance, but it does take planning and the right mindset.


    The transition to the collegiate level is an exciting challenge for all. NCAA swimming represents some of the fastest swimming on the planet. Freshmen can establish a foundation for a successful swimming career by entering school with right mindset and by knowing where the most critical challenges reside. 

    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.

    Drills to Ditch: Side kicking and 6-beat switch

    Take Home Points on Drills to Ditch
      1. Hip rotation may contribute less to rotation than previous belief
      2. Hip stability is crucial for energy transfer
      3. Reconsider drills that teach hip rotation beyond the degree used in the full stroke
        Many non-scientific beliefs exist in swimming. One form of dogma is the role of hip

        rotation in long axis strokes.  Conventional wisdom says that increasing hip rotation is critical for propulsion, hydrodynamics, and healthy biomechanics.  While most would agree that a completely flat stroke devoid of any rotation is suboptimal, there’s great uncertainty in how much is optimal, both in general terms and for each individual.

        Some factors that may dictate hip rotation include:
        • Individual stroke preferences: Different types of freestyle (Body Roll in Freestyle)
        • Injury patterns: Some swimmers must adjust their strokes to avoid pain, as everyone brings different alignment to the pool.
        • Event: It has been suggested that sprinters require less hip rotation than middle distance and distance swimmers.
        • Kicking patterns: 2 beat versus 6 beat kick may dictate body roll patterns.
        Unfortunately, most data on hip rotation comes from the naked eye and from 2D still and video images.  Unlike land based sports such as baseball, golf, and tennis, there is far less data on swim strokes readily available to the coach.  Still there has been enough research for authors such as Maglischo (2003) to conclude,

        "Rolling the body from side to side is essential to efficient front-crawl and backstroke swimming, although not for the reasons usually espoused.  Body roll does not add to propulsive force, except indirectly."

        In an interview on this site, Dr. Jan Prins noted from research in his own lab (paraphrased):

        "Because water is unstable, stability must come from the hips. Hips are translators of velocity and roll in reaction to movements of the hands and feet. Hip velocity tells us how fast you are going. People assume you roll your body but that is incorrect. Previous biomechanical models were based on fixed resistance (land), but water is an unstable medium. Hip stability allows force transfer initiated by the hands and feet. Roll occurs naturally via arm extension. Don’t try to swim on your side like a fish." 

        Previously, Dr. John had begun a series on drillsto ditch segment focusing on traditional drills that deserve rethinking.  The discussion here begs the question whether drills involving side kicking merit continued use in light of what we know (or don’t know) about hip rotation.  Now, if the purpose of the drill is to improve side kicking (such as out of a wall), then perhaps that is more defensible.  But if the goal is to teach a swimmer to swim on their side mid-pool, the latter justification seems to sit on shakier ground. 

        Two drills coming to mind are side kicking and 6-kick switch on side.  Both drills may have merit for coaching beginners with zero concept of body rotation, but do they have merit for anyone beyond the beginner level (if even for novices?)?  Ultimately, there is no definitive answer, but given what the trends are regarding hip stability, perhaps any attempt to exaggerate hip rotation may infect the overall stroke pattern that we are aiming for. 


        While part of this post is as much theory and conjecture as the drills themselves, it does reflect how much is still unknown in this area.  Anecdotally there seems to a movement away from emphasizing hip rotation for the sake of hip rotation, as many now recognize that more factors come into play.  Ultimately, our drill selection should follow accordingly with changes in knowledge.    

        1. Maglischo, E.  Swimming Fastest.  Human Kinetics.  2003
        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.

        Burnout Among Swim Coaches

        Take Home Points on Burnout Among Swim Coaches
        • Burnout among coaches is a “brain drain” on the sport.
        • Athletes may suffer if coaches are burned out.
        • Understanding causes of burnout is critical for long term development and retention of coaches.
        Burnout is a common but unfortunate topic in the swimming community. (Why do Young
        Swimmers Burnout? and How to Prevent Swimming Burnout) Many swimmers hang up the goggles long before reaching their potential. Sometimes frustration due to injury discourages swimmers from pressing onward. Other times, burnout is purely mental, where a swimmer is fed up with staring at the black line and living by the strict rhythm of the pace clock. 

        Now, no one said swimming (or any sport) at a high level is easy, so attrition is a natural byproduct of rising through the ranks. But most would agree that burnout is far too common. Veterans of the sport all know several swimmers who left the pool early with unmet physical potential. 

        Burnout among swimmers is frequently discussed, but what about burnout among coaches? Coaching swimming can be a tough gig…long and irregular hours, lost weekends, external pressure (parents, institutional, athletes). As a result, many coaches leave the profession before reaching their potential as coaches. This topic is especially poignant with many coaches desperately looking forward to some rest and relaxation after summer season. 

        If a young coach leaves the sport due to burnout, many mentorship hours have been squandered in the process. Secondly, burnout is not sudden, and many coaches aren’t able to give their athletes their very best if they are on the road to burnout. Additionally, potential coaches may be discouraged from entering the field if they suspect burnout will occur, which can contribute to negative self-fulfilling cycles. 

        Though swim coach burnout has not been a hot topic in research-land, there is still much to learn from other sports that have been studied. A survey among Turkish judo coaches (Gencay 2011) revealed “moderate” levels of burnout among those studied. The point here is not to study judo, but instead to explore generally why do coaches burnout? 

        This study found that coaching experience and (lack of) satisfaction from administrators both factored into emotional exhaustion. Authors concluded, “Burnout appears to be a problematic issue for judo coaches. When coaches begin to feel emotionally depleted, they distance themselves from athletes, and experience a reduced sense of meaning about their work; it is likely to affect the quality of the athletic experience for both the coach and the athletes.”

        Malinouskas (2010) found similar correlations among university coaches, with experience greater than 10 years being related to burnout, though gender was not related to burnout. Yet burnout has many dimensions beyond strictly mental depletion. Tashman (2010) studied coaches from multiple sports and found that maladaptive perfectionism (as contrasted with adaptive perfectionism) was linked to burnout.

        Additional research from the world of athletic training also can offer insight. Though athletic training is a completely different field than coaching, the job stresses are very similar: long irregular hours, pressure to perform, low to moderate pay relative to time worked. 

        “No matter their marital or family status, ATs employed at the Division I-A level experienced difficulties balancing their work and home lives. Sources of conflict primarily stemmed from the consuming nature of the profession, travel, inflexible work schedules, and lack of full-time staff members.” (Mazerolle 2008)

        Some of these factors are inherent for any job at high levels of sport. Travel and long hours are unavoidable, but other stressors can be managed. One similar theme that emerges is the role of leadership. In the coaching context, head coaches and administrators can shape the future of assistant coaches. 

        While there is certainly a balance to be had between being too tough and too lax, leaders in the field must recognize the influence they have on their subordinates. “The foundation for a successful work environment in the NCAA Division I clinical setting potentially can center on the management style of the supervisor, especially one who promotes teamwork among his or her staff members. Although a family-friendly work environment is necessary for work-life balance, each member of the athletic training staff must have personal strategies in place to fully achieve a balance.” (Mazerolle 2013)


        Despite the dark and gloomy tone of this article, most would agree that more viable opportunities exist in the coaching field than in the past. Performance levels among young swimmers continue to elevate, in part due to more free access to knowledge for young coaches. But the sport can always do better in cultivating young coaching talent. Understanding what potentially drives some coaching prospects out of the field is one step in the right direction. 


        1. Gencay S1, Gencay OA. Burnout among judo coaches in Turkey. J Occup Health. 2011;53(5):365-70. Epub 2011 Jul 20.
        2. Malinauskas R1, Malinauskiene V, Dumciene A. Burnout and perceived stress among university coaches in Lithuania. J Occup Health. 2010;52(5):302-7. Epub 2010 Aug 6.
        3. Tashman LS1, Tenenbaum G, Eklund R. The effect of perceived stress on the relationship between perfectionism and burnout in coaches. Anxiety Stress Coping. 2010;23(2):195-212. doi: 10.1080/10615800802629922.
        4. Mazerolle SM1, Bruening JE, Casa DJ. Work-family conflict, part I: Antecedents of work-family conflict in national collegiate athletic association division I-A certified athletic trainers. J Athl Train. 2008 Sep-Oct;43(5):505-12. doi: 10.4085/1062-6050-43.5.505.
        5. Mazerolle SM1, Goodman A. Fulfillment of work-life balance from the organizational perspective: a case study. J Athl Train. 2013 Sep-Oct;48(5):668-77. doi: 10.4085/1062-6050-48.3.24.
        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.

        Does Altitude Training Work for Swimming?: Part II

        Take Home Points on Does Altitude Training Work for Swimming?: Part II
        1. Individuality is a key point in recent literature on altitude training.
        2. Altitude may change biological markers, but changes in race swim speed are uncertain.
        3. Despite the prevalence of individuality, individual response is not a fixed trait.
        Altitude training is always a controversial topic in swimming and sports as a whole.  We
        have covered this topic before, but it is worthwhile to review the recent literature to note recent updates.  Many teams have taken swimmers to altitude locations during the summer and are anticipating meaningful improvements at late summer long course meets. 

        One key point in recent literature is how responses to altitude training are highly individual.  Though teams will often take an entire squad to an altitude site, swimmers under the same program may respond in highly varied ways to similar workouts.  Whereas certain athletes thrive on altitude, others may be overstressed just by the altitude exposure before factoring in training.  As Chapman writes (2013),

        “some athletes are clearly more negatively affected during exercise in hypoxia than other athletes. With careful screening, it may be possible to develop a protocol for determining which athletes may be the most negatively affected during competition and/or training at altitude.”

        Screening protocols may be effective but altitude responsiveness is a moving target.  McLean (2013) studied elite footballers in 19 and 18 day training camps at altitude spaced on year apart.  Most swimmers improved physiological markers through altitude training, but “the same individuals generally did not change their hemoglobin consistently from year to year. Thus, a 'responder' or 'non-responder' to altitude for hemoglobin does not appear to be a fixed trait.” 

        Many studies such as the one cited above will measure progress through hemoglobin levels.  But is this change in physiology meaningful to actual swimming performance? 

        Boone (2014) studied elite swimmers at a 3-4 week “live high-train high” altitude camp and compared them to a similar group training at sea level.  Authors noted that the altitude group improved hemoglobin mass and swim performance in the incremental step test and in the 3000m time trial more than the sea level group.  There was no significant difference between groups in the 4 x 50m test, though both groups did improve.  Thus, at least in this study, altitude appeared beneficial for swimming performance (but did they actually race faster when it mattered?). 

        Garvican-Lewis (2013) studied elite water polo players in Australia over repeated exposures to altitude training and likewise found improvements in hemoglobin mass.  However, because competition performance is determined by many factors (especially in water polo), authors were guarded with the conclusion "since match performance is nuanced by many factors it is impossible to ascertain whether the increased hemoglobin contributed to Australia's Bronze medal."


        As always with altitude training, remember that potential benefits may result from repeated exposure or through a sequestration effect in which swimmers may have the opportunity to focus on training without real world distractions.  Despite the abundance of literature, there’s still much we don’t fully understand.    

        Though there is nothing groundbreaking in the recent literature, be reminded about the importance of individuality, especially when it much more convenient to package a team into a single training plan at a camp.  Also critical is that responses within individual athletes may change over time.  


        1. Chapman RF.  The individual response to training and competition at altitude.  Br J Sports Med. 2013 Dec;47 Suppl 1:i40-4. doi: 10.1136/bjsports-2013-092837
        2. Bonne TC1, Lundby CJørgensen SJohansen LMrgan MBech SRSander MPapoti MNordsborg NB.  "Live High-Train High" increases hemoglobin mass in Olympic swimmers.  Eur J Appl Physiol. 2014 Jul;114(7):1439-49. doi: 10.1007/s00421-014-2863-4. Epub 2014 Mar 27.
        3. Garvican-Lewis LA1, Clark SAPolglaze TMcFadden GGore CJ.  Ten days of simulated live high:train low altitude training increases Hbmass in elite water polo players.  Br J Sports Med. 2013 Dec;47 Suppl 1:i70-3. doi: 10.1136/bjsports-2013-092746.
        4. McLean BD1, Buttifant DGore CJWhite KKemp J.  Year-to-year variability in haemoglobin mass response to two altitude training camps.  Br J Sports Med. 2013 Dec;47 Suppl 1:i51-8. doi: 10.1136/bjsports-2013-092744.

        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.

        How Good is the Swimming Science from 2013?

        Take Home Points on How Good is the Swimming Science from 2013?

        1. In the last year it was published a good mix of papers dealing with elite (25%), age-group (27%) and sub-elite swimmers (31%)
        2. Vast majority of the papers are interdisciplinary (31.34%), biomechanics (25.37%) and physiology researches (20.90%)
        3. Swimming research was published in journals with a mean impact factor of 1.570 and median of 1.600
        4. Papers were published mainly in the first (21%), second (31%) and third (42%) quartiles.

        What have in common academics and swimmers? Probably not so much, but their performances are measured, quantified in a more or less accurate way (more accurate for swimmers; less for academics, should I say). There are databases to benchmark academics, research groups, journals and scientific fields. Several parameters can be selected to quantify the impact of one’s research. For today I will cover only two: (i) journal impact factor; (ii) journal quartile score.

        The impact factor is a ratio between the number of papers a journal publish per year and the number of times papers from the same journal are cited. So, if in 2012 one Journal published 50 papers and got 75 citations, its impact factor is 75/50=1.500. Highest the impact factor, the better.

        The other parameter is the journal quartile score. After calculating the impact factor of all journals in a scientific field, they are ranked from the highest to the lowest impact factor. Thereafter, the ranking is chopped into 4 equal parts. Let’s consider that there are 16 papers in a given scientific field. We rank the 16 journals according to the impact factor. The journals ranked between: (i) the 1st and 4th place are the first quartile; (ii) 5th and 8th place, second quartile;  (iii) 9th and 12th, third quartile; (iv) 13th and 16th, fourth quartile. The first quartile is the best and the fourth the poorest.

        After providing this background, we are in conditions to learn how good is the swimming research published last year. The aim of this analysis was to describe the production of swimming “science” in one full year. A search of the literature (figure 1) was conducted between May 1st 2013 and April 31th 2014 on the ISI Web of Knowledge (WOK) under the “Sports Science” category (Journal Citation Report - 2012 Science Edition). Search strategy was similar to what was reported by Costa et al. (2012). Several keywords (e.g., “swimming”, “front-crawl”, “backstroke”, “breaststroke”, “butterfly”, “swimmer”, “young”, “age-group”, “elite”, “master”) were used in the search strategy, with multiple combinations. Inclusion criteria were as follows: (i) original research papers; (ii) in English; (iii) published in journals indexed in the WOK; (iv) focusing on competitive swimming; (v) involving human subjects.

        For the papers included in the analysis it was determined the: (i) type of subjects recruited; (ii) scientific field of research; (iii) journal impact factor; (iv) journal quartile ranking. The type of subjects recruited was breakdown into: (i) age-group; (ii) sub-elite; (iii) elite; (iv) master; (v) fitness- & teaching-oriented; (vi) mixed groups. It was considered as research fields & topics (adapted from Clarys, 1996): (i) Biomechanics; (ii) Psychology; (ii) Sociology; (iii) Pedagogy/Teaching; (iv) Biochemistry; (v) Physiology; (vi) Thermoregulation; (vii) Hydrodynamics; (viii) Electromyography; (ix) Anthropometry; (x) Equipment/Methodologies; (xi) Clinical Medicine/Traumatology and; (xii) Interdisciplinary assessment.

        What can we learn as practitioners and swimmers?

        We have a good mix of papers dealing with elite (25%), age-group (27%) and sub-elite swimmers (31%) (figure 2). Several countries around the world are putting a lot of effort to come up with talent ID schemes in the road to major competitions to be held between 2020 and 2024. This may explain why almost one third of the papers are about age-group swimmers. Traditionally researchers are fancy to carry out their projects with adult swimmers (31%+25%; sub-elite + elite). It is interesting to note that one quarter of the research is about top-level swimmers. In other sports, such as cycling and athletics, one of the main criticisms is that research is conducted mainly with subjects with poor competitive level but then transferred to top-level athletes which might be misleading and misguided. In swimming it seems the body of knowledge gathered is specific of the age group and competitive level, so allegedly the transfer of knowledge from academia to real-world should be smooth and easy. As you may understand I have a conflict of interest on this. So I will refrain to elaborate much more. 
        There are some areas still to explore though, such as master swimming (2%) and fitness- & teaching-oriented swimming (6%). Mixed groups, e.g., comparing subjects with different competitive levels or age groups represent only 9%. So, one might say that master swimming and teaching to swim seems to be less evidence-based. Nevertheless I should acknowledge that as we speak several research group have ongoing research projects about master swimming. There is also a journal with a scope very unique, aiming to disseminate research about noncompetitive swimming, more focused on teaching and learning of aquatic skill, but unfortunately it is not indexed in the WOK. So, hopefully we will see more research coming up on this topic in a near future.

        The vast majority of the papers did interdisciplinary assessments, i.e. have a holistic approach to swimming (figure 3). Comparing these figures with the content of the proceeding book of the “Biomechanics and Medicine in Swimming” symposium in 2006 (Barbosa et al., 2010) or what was reported in the late 1990s by Clarys (1996) the holistic research has been increasing and becoming the main trend.

        But what is studied in these researches? What fields? 

        With no surprise, Biomechanics and Physiology. Performance, Biomechanics and Physiology are the main topics when it comes to swimming, right? Doesn’t matter if we are talking about research or practice. For instance, what are the details we hear (or we should hear) most of the times to monitor a training set? a) split times (i.e. Performance); b) heart rate or rate of perceived effort (i.e. Physiology); c) stroke counts (i.e. Biomechanics). 
        When Clarys (1996) suggested this breakdown of the swimming topics, some were very hot and trendy those days, not any longer. To be more accurate some topics are part of the biomech or physio fields. E.g. Hydrodynamics (5.97%) and even anthropometry (1.49%) may be considered as topics under biomech (17.91%; 5.97+1.49+17.91=25.37%). Same goes for Biochemistry (8.96%) and Thermoregulation (1.49%) that are part of the physio (10.45%; 8.96+1.49+10.45=20.90%). 
        How about electromyography (4.48%)? Well there is a blurred line splitting Biomechanics from Physiology, which is the electromyography. For some people electromyography should fall under the Biomechanics, for others the Physiology. I will skip such academic discussion for now. Other topics of interest are the Clinical medicine (5.97%), as well as the development of equipment and specific methods for assessment in swimming and aquatic environment (2.99%).

        What can we learn as academics and researchers?

        Nowadays aquatic research involves several other sports besides competitive swimming. Forty-nine papers excluded deal with sports such as Water Polo, Synchronized swimming, Triathlon, etc. A lot of fundamental research is also conducted with animal models and not with humans (18 papers excluded studying e.g. fish and rats). It has been published almost one paper per week (67 original papers published in one full year).
        On average swimming papers are published in journals with an impact factor of 1.570, which is very close of the mean impact factor of all Sport Science domain (table 1). The median is slightly higher for the swimming papers than remaining Sport Science domain (table 1). The impact factor of Sport Science domain is rather low, at least so far. Just to have an idea, the well-known Nature, Science and Lancet journals have impact factors of 38.597, 31.027 and 39.060, respectively. Sport Science is a very specific and recent scientific field with let’s say 60 years of existence. As discussed in another post, the research in Sports Science (and Swimming “Science”) started in the 1960s and 1970s, but boosted a couple of decades later. So, I am wondering how come we can compete with fundamental sciences that have centuries of existence, such as Mathematics, Physics, Biology, Chemistry, etc.

        Papers published in the first (21%) and second (31%) quartiles represent 52% of the body of knowledge (figure 4). Better papers are published in those quartiles, so it seems that we have good pieces of research being published lately. However, 42% of the papers were published in the third quartile. Hence, swimming is quite mainstream, in the sense that does not show a better or worse impact than remaining Sport Science.
        The big challenge seems to be publishing in the top-tier journals, e.g., top-5. The original paper with the highest impact factor was published in the journal ranked in 8th place. One might say that most top-tier journals have a “fundamental” or broader scope (i.e. not so applied and specific of a given sport) or have a higher number of slots available for review papers. Indeed at least one of the papers excluded is a review published in the journal ranked as 3rd (figure 1).


        1. Barbosa TM, Pinto E, Cruz AM, Marinho DA, Silva AJ, Reis VM, Costa MJ, Queirós TM (2010). The Evolution of Swimming Science Research: Content analysis of the “Biomechanics and Medicine in Swimming” Proceedings Books from 1971 to 2006. In: Kjendlie PL, Stallman RK, Cabri J (eds). Biomechanics and Medicine in Swimming XI. pp. 312-314. Norwegian School of Sport Science. Oslo.
        2. Clarys JP (1996). The historical perspective of swimming science. Foreword to the Biomechanics and Medicine in Swimming VII. In: Troup JP, Hollander AP, Strasse D, Trappe SW, Cappaert JM, Trappe TA (eds). Biomechanics and Medicine in Swimming VII, pp. xi-xxxiv. E & FN Spon, London.
        3. Costa MJ, Bragada JA, Marinho DA, Silva AJ, Barbosa TM (2012). Longitudinal interventions in elite swimming: a systematic review based on energetics, biomechanics and performance. J Strength Con Res. 26: 2006-2016
        By Tiago M. Barbosa that earned a PhD degree in Sport Sciences and holds a faculty position at the Nanyang Technological University, Singapore