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Thoughts on the Crawl Stroke

Why are the Australian men making such incredible advances in freestyle events from 200 to 1500 meters? It is a result of the outstanding application of an old technique applied by superior athletes who are well-trained and highly motivated.

The outstanding performances by the Australian men's freestylers in recent years have elicited much speculation as to how they are accomplishing such feats. The most recent world records by Ian Thorpe in the 200 and 400 meter freestyles are the latest testaments to the strength of freestyle swimming by Australians.

The Aussie men now own the world records in all of the freestyle events from 200 to 1500 meters. And with Alex Popov now living and training in Australia, it could be argued that the Land Down Under is the place to be if freestyle success is your quest.

What is it that has separated the Australians from the rest of the world in the crawl stroke?

I believe the Australians are using an old technique first performed by Murray Rose in the 1950s and subsequently described by Charles Silvia in kinesiological terms. It is the outstanding application of this technique that is obvious when viewing the underwater video of these great Australian freestylers. Speculation about the rest of the world's lack of competitiveness with the Australians could center upon the peculiarities of Australian technique. And it is my belief that it is Australian technique that is the major reason for Australian dominance in freestyle events.

The excellent underwater video taken at the Barcelona Olympic Games showed Kieren Perkins' superior stroke technique while he was setting the world record in the 1500 meter freestyle. It was then that I noted the similarity between the technique of Perkins and the technique of Murray Rose. After the Games in an article in American Swimming Magazine, Perkins' coach, John Carew, stated that Perkins' stroke is based on the stroke of Murray Rose. The evidence that this technique is superior is compelling. Perkins has swum 20 seconds faster than any American for 1500 meters. And the only challenge to Perkins' superiority has come from his own national teammates.

But the performances such as Perkins' are often dismissed as freak events. Bob Beamon's long jump at the Mexico City Olympics or Mary T. Meagher's 200 meter butterfly in 1981 are examples that come to mind. These athletic performances were so superior to the rest of the world that the competition seemed to be playing a different game. Add to this the most recent world record performances of Ian Thorpe in the 200 and 400 meters, and the dominance of the male Australian 4 x 200 relay, and a pattern of individual superiority, as well as team depth in Australia, begins to emerge.

Obviously, many factors can contribute to superior performance. Thomas Cureton identified four factors that together determine athletic success. These factors include training methods, body types, the determination of the athlete, as well as technique. It is not the purpose of this article to belittle the importance of training methods, body types and determination of the athlete in producing outstanding results. Certainly, the Australians possess outstanding programs and superior motivated athletes. And their other stroke specialists are also competitive at the world-class level. But it is in the male freestyle events of 200 to 1500 meters that the Australians are dominating. The dominance of so many events, by such significant margins, in the most common of strokes has to raise the eyebrows of swimming coaches everywhere.

Charles Silvia described the great Murray Rose's stroke as possessing four distinct parts that together formed a stroke that was humanly mechanically superior. The 'Big Four,' as Silvia named it, are: Inertial shoulder girdle elevation and upward scapular rotation Shoulder joint medial rotation and elbow flexion Shoulder joint adduction and downward scapular motion Inertial round-off and release (partial supination and shoulder joint lateral rotation).

Silvia also advocated the drag theory of swimming propulsion, and that theory has been debated in recent years, but his kinesiological analysis of the mechanics of Rose's stroke has not been successfully challenged.

Stroke Characteristics

What are the stroke characteristics that the current Australian star freestylers show that may be lacking in many of their competitors?

Number one is their form, which essentially follows the description of Silvia's 'Big Four.' Most notable is the catch at the beginning of the propulsive phase of their strokes. Silvia would have described this as an inertial positioning movement before the main propulsive phase begins.

At this point in the stroke, it is obvious that the great Australian freestylers take the time to assume the high elbow position about which all good coaches talk. They accomplish this act by internally (medially) rotating the upper arm bone (humerus) and flexing the elbow. This action ends with the forearm and hand assuming an almost perpendicular position in relation to the surface of the water, before the elbow is moved (adducted) toward the feet. The positioning movement of the arm takes place in the shoulder with very little muscular force.

It is after the catch that the true power and efficiency of the Australian crawl stroke technique is exhibited. It is during this most propulsive phase that the Australians use the power of the shoulder joint most effectively by adducting the upper arm bone (humerus) along the frontal plane (the plane that divides the front of the body from the back) of the body.

This is the same movement a gymnast would use in performing the iron cross on the still rings. The only difference between the gymnastic and swimming actions is in the flexion of the swimmer's elbows to increase the mechanical advantage of the arm's lever system. This position also fits beautifully the position needed to apply force backward with the hand and forearm that is required in the drag theory of propulsion.

The swimmer's muscular action, also, is not static. The elbow is brought vigorously toward the body (adduction). It is the great prime movers of humeral adduction, the teres major, latissimus dorsi and the pectoralis major that perform the bulk of the task. These muscles are most effective when their angles of pull follow closely along the frontal plane of the body. This most powerful movement of the shoulder joint is demonstrated skillfully in the crawl stroke swimming of the current flock of Australian male world-class swimmers.

It also stands to reason that the most powerful movement of the shoulderÑadduction of the upper arm bone (humerus) along the frontal plane of the body (the plane that divides the body from front to back)Ñis the so-called 'swimming with the trunk of the body, or core' that is now being promoted by many coaches. This is because it is the great muscles of the trunk that perform the bulk of the task.

The long, propulsive phase of the great Australian swimmers is finished with the completion of adduction, and the recovery is initiated by rounding off the stroke and partially supinating the hand (turning the palm toward the body).

The supination of the hand effectively releases the swimmer's feel for the water as the swimmer redirects the momentum of vigorous adduction into an inertial recovery. The elbows of the Australians remain bent as they finish their strokes so that the mechanical advantage of the shortened lever arm can be maintained.

The bent elbow finish is important because the intuitive swimmer knows that the advantage of pushing past the hip by extending the elbow does not contribute to an inertial, free swinging and non-muscular recovery. This recovery is a bit different from the butterfly.

The butterfly recovery cannot rely on trunk rotation. And the more lateral recovery in the butterfly requires a straight elbow to prevent excessive lifting of the shoulders to clear the water at the beginning of the recovery. The rotation of the trunk on its long axis as adduction is completed adds to the disadvantage of extending the elbows in the crawl stroke as the hand effectively loses its propulsive grip on the water at the completion of adduction.

It is important to note that the 'core or trunk' swimming of the great Australian freestylers emphasizes the motions of the largest and most powerful muscles of the trunk while minimizing the involvement of the smaller muscles of the arm and forearm. It is in describing these actions that the importance of correct language becomes apparent.

The action of adduction along the frontal plane of the body will cause the arm to be moved in a curvilinear arc (the arm being a lever system with the fulcrum at the shoulder end). It is not necessary for a swimmer to try to stroke in 'S' patterns or to think to move in downsweeps, outsweeps, insweeps and upsweeps.

Emphasis of these sweeping actions could easily confuse the swimmer into making motions not congruent with the true power of the shoulder joint. One of the major problems of describing technique with sweeps and 'S's' is that they describe actions that can be interpreted in many different ways. An 'S' sweep done in front of the body is much different from an 'S' sweep beside the body.

And, any exaggeration of sweeping actions would naturally deviate from the power of adduction and the strength inherent in the great trunk muscles. In addition, the resulting actions would greatly increase the involvement of the smaller muscles of the arm and forearm, resulting in early fatigue.

Scholarly Theories

It was stated earlier that Silvia's kinesiological descriptions of technique have not been successfully refuted. It was his reasoning that this technique fits the drag theory of force that has been in question. Ever since Doc Counsilman first professed lift as the major force of swimming propulsion in the early '70s, and others have promoted it such as Ernie Maglischo in his widely circulated books, 'Swimming Faster' and 'Swimming Even Faster' in the '80s and '90s, Silvia's ideas have collected dust. It was unfortunate that Silvia's descriptions were mostly ignored because they were so accurate, even if his theory of propulsion was considered antiquated.

Counsilman's lift theory promoted the use of curvilinear motions to produce propulsion. In the lift model, the hand formed an airplane-type wing that, when moved sideways to the direction of travel, created lift.

Silvia's drag model of propulsion followed Newton's Third Law, 'for every action there is an equal and opposite reaction.' The mounting evidence in research supports Silvia's ideas on propulsion.

Springings and Koehler in their article, 'The choice between Bernoulli's or Newton's model in predicting dynamic lift,' lay bare the arguments supporting lift as the primary or even a significant force in swimming. Maglischo is now reconsidering lift theory and is revisiting Silvia's ideas, but if technique is as important as most world-class coaches believe, the promotion of a flawed theory for an extended time by influential thinkers, coaches and authors would be an obvious detriment to swimming progress.

Unfortunately, the use of inaccurate and misleading descriptions of crawl stroke technique, including 'S' curves and sweeping actions, is exactly what the lift theorists have promoted in this country for over 20 years. These descriptions remain even as the theory of lift is refuted.

It is the contention of this writer that one of the main reasons the Australians are now so superior to the rest of the world in the male freestyle events from 200 to 1500 meters is that their technique follows a mechanically superior model. Theories of propulsion used in Australia take a back seat to what produces results. While the model for technique in the United States and elsewhere has been promoting actions that are not congruent with the strength of the shoulder joint, the Australian model does the exact opposite.

It could be argued that the United States has been competitive in the sprint freestyle events even up to the 400 meters in recent years. Thus, the argument in the previous paragraph would be flawed.

However, the quick nature of sprinting events demand intuitive swimmers who naturally avoid the time wasting and excessively inefficient curvilinear motions being promoted.

The vast American talent pool has been able, thus far, to find and develop successful sprinters. The Australians have a talent pool seven percent of the United States and have produced world records starting with Kieren Perkins in the 1500 and ending with the most recent world records of Ian Thorpe.

It is now not a stretch to think that the Australians could add the 50 and 100 meter world records if the proper athlete could be found to match their superior technique.

Perhaps with maturity that athlete could be Ian Thorpe. He certainly has shown the speed to be competitive with his 48.55 split in the 4 x 100 relay at the Pan Pac Championships in 1999. In the meantime, the United States, which has been competitive in most freestyle events, now finds itself with competitors who are significantly slower than the Australians in a number of freestyle events.

It is interesting to note that it not just the likes of world-class performers such as Ian Thorpe, Grant Hackett and Kieren Perkins who are currently exhibiting this peculiar technique in Australia. Dick Hannula attended a training session of Ian Thorpe and Grant Hackett in May 1999 while he was visiting Australia to speak at the Australian Swimming Coaches and Teachers Association Convention. A local swim club was practicing at the same time as the national team members, and he noted that the age groupers were using the same basic technique.

Hannula states in his observations of their freestylers that there were no sideward sweeps. He also notes that this technique is not what is described in textbooks. Whether or not Australian coaches understand kinesiological principles, the Australians obviously follow a superior stroke model that is promoted at the earliest levels of competition.

Hannula goes on to state that, while this technique appears to be a new innovation, he has seen it as far as 15 years or more ago in sprinters such as former American record holder Robin Leamy. As stated earlier, this stroke technique can be seen as far back as Murray Rose in the 1950s. And, since Rose was a distance freestyler, it is a stroke that has been used by freestylers at every distance.

Other Hypotheses

Other hypotheses have been presented over recent years concerning the lack of progress of the male distance freestyle events in the United States. These hypotheses include both cultural and coaching issues. The cultural hypothesis states that there are fewer and fewer athletes in the United States willing to do the work required for success in the distance events.

Our fast-paced society, with its emphasis on instant gratification, might be discouraging talented athletes from pursuing distance events. Also, there is more competition from other sports and activities outside sport. All these distractions add up to a negative result at the top of the performance ladder.

The coaching hypothesis points to the disproportionate number of swimming programs that emphasize sprinting because the overwhelming majority of swimming events are sprints.

While both of these arguments are worthy of consideration, I do not believe the key answer lies in their conclusions. These arguments needlessly berate and belittle the hard work and dedication of the current national and world-class stars of American distance swimming. All world-class swimmers, regardless of their event, know there are no short cuts to success. And the American successes in other swimming events show the dedication and depth of swimming in the United States. And, once a swimmer sees the possibilities of international competition, the motivation to do what it takes to succeed is universal.

Ian Thorpe's Stroke

Brent Rushall on his internet page describes in detail the stroke of Ian Thorpe as he set the world record in the 400 meter freestyle last summer at the Pan Pac Championships. The frame-by-frame analysis shows the champion's stroke that, again, fits the description of a stroke Silvia would have promoted, or anyone else for that matter. It is in the understanding of what they see that theorists differ.

Again, the general mechanical description Silvia used with his 'Big Four' essentially could be used as a description of Thorpe's stroke. Rushall notes in his analysis a few peculiarities in Thorpe's stroke that are not included in Silvia's 'Big Four.' While not essential to nor negating the premise of the 'Big Four,' these peculiarities are significant enough to warrant a discussion of their nature.

Rushall notes the apparent catch-up nature of Thorpe's stroke. This is described as the duration of the recovery (four-tenths of a second) and the duration of the pull (one second for the right hand and 1.1 seconds for the left hand).

This imbalance between recovery and propulsive phases (0.4 sec./1.0 sec. and 0.4 sec./1.1 sec.) can be explained through a discussion of the forces involved. The recovery naturally will take less time as it takes place over water, inertially and with little resistance.

Thorpe does not rush the initial part of the propulsive phase of his stroke, as he takes the time to position the hand and forearm by medially rotating the humerus and flexing the elbow. It is once this position is attained that the prime movers of adduction vigorously contract against the resistance of the water.

Adduction continues until the elbow almost touches the body. At this point, round-off, partial supination of the hand and the release take place. These actions against the resistance of the water naturally take more time than the recovery. Any effort on the part of the swimmer to slow the recovery to maintain opposition will negate the advantage of an inertial and non-muscular recovery.

At this point in the discussion, it could be argued that Thorpe's stroke could be improved by maintaining the bent elbow of the recovery to decrease the inertial lag time taken as the arm is stretched out straight during the entry phase of the stroke.

However, this action would not allow for full inertial shoulder girdle elevation described in Silvia's 'Big Four,' and would negate the ending of the propulsive phase of the opposing arm. The resulting stroke would be shortened and less effective during the initial propulsive phase.

Clearly, Thorpe does not rush his stroke, and he takes the time to complete each phase. There is no inefficient hurry-up, or 'spinning of wheels,' that is often exhibited by less talented swimmers.

Thorpe's apparent lack of speed in assuming the medial rotated position with elbow flexion is the result of the inertial completion of the recovery phase. Very little muscular force is used to gain this position. The speed of the hand and the arm when the hand and arm were recovering out of the water has slowed with the added resistance of the water.

Rushall describes two 17-frame clips of Thorpe during his 400 meter world record at the Pan Pacs in 1999. One clip is taken at 75 meters into the swim and the other clip is taken at 375 meters into the swim. Each frame is one-tenth of a second apart and makes the total sequence of each clip 1.7 seconds long. It appears that the final two frames of each clip are a repeat of the first two frames. This would make the stroke cycle 1.5 seconds long in each clip.

The first five frames of the sequence taken at the 375 meter mark of the race show the right arm with the elbow completely extended. Not until the sixth frame does any elbow flexion become apparent. This would suggest that one-half of the in-water phase of the stroke cycle of Ian Thorpe is non-propulsive and that little or no pushing down or out takes place during this phase of the stroke.

Any increase in the muscular force to produce this positioning movement would be detrimental to the stroke.

The efficiency of Thorpe's stroke lies in his ability to get into the medial rotated position with elbow flexion while the arm is still fully abducted and the shoulder girdle is elevated (the position an eager child uses when he raises his hand to answer a teacher's question) and before the arm begins its forceful adduction movement.

This manifests itself as a position that allows the hand and forearm to gain almost a perpendicular position in relation to the surface of the water before the elbow passes the top of the head during adduction.

The fact that Thorpe takes five-tenths of a second to accomplish this movement in a 1.5-second total stroke cycle demonstrates the importance of this positioning movement to the stroke.

Clearly, Thorpe takes the time to achieve the medial rotated position, and he does it inertially and with little antagonistic muscular interference. Any increased muscular force used to speed up this positioning movement would not add significantly to propulsion and would involve the internal rotator muscles of the rotator cuff and the large adductors that are also involved with the main propulsive phase of the stroke which follows.

The advantage of the inertial positioning movement of medial rotation instead of a vigorous muscular action involves the size, nature and positioning of the muscles involved. The rotator cuff muscles are relatively small muscles whose main purpose is to serve as tendons to hold the head of the arm bone (humerus) into place in the shoulder joint.

Any emphasis upon these muscles to provide more than stabilization of the shoulder would invite early fatigue. Vigorous contractions of the other internal rotators which are also major adductors of the humerus, the latissimus dorsi, pectoralis major and the teres major, would be an ineffective recruitment of muscles at an ineffective angle of pull.

Certainly, the inertial positioning of internal rotation is promoted by an effective kick that allows the entry hand to be positioned as the body continues to provide propulsion with the kick. This is demonstrated by Thorpe and illustrated with the sensation a swimmer gets when swimming with flippers.

The flippered swimmer has the sensation that the arm stroke is too easy, especially during the early positioning phase of the stroke. It is my opinion that this is what Ian Thorpe must feel as he swims. And, knowing the size (17) and flexibility exhibited in Thorpe's feet, the advantage of superior body structure only adds to an already efficient technique. The inertial and non-muscular nature of two-thirds of Ian Thorpe's stroke (the recovery and catch phases) adds to the endurance of the swimmer.

Making It Look Easy
All good swimmers make it look easy, and in this case, it most certainly is, from the standpoint of efficiency.

Surely, there is no one who has exhibited the perfect stroke or race. But something has to explain the current superiority of Australian male freestylers. There is not just one freak individual performing outstanding feats. There is a whole group of Australian male swimmers who, together, form a very formidable team.

The current Australian stars emulate a technique that is best described by the drag theorists and follows the kinesiological model of what is humanly mechanically superior. The current Australian superiority in the freestyle events is a result of the outstanding application of an old technique applied by superior athletes who are well-trained and highly motivated.

I believe that it is the technique of the Australians that is the greatest factor in separating the Australians from the rest of the world-class swimmers. And no amount of training, outstanding body type or determination on the part of the athlete will make up for the lack of the application of this technique.

About the Author
Marshall Adams is the swimming coach at the Cincinnati Country Day School in Ohio.

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