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Cecil M. Colwin
HOW THE WATER REACTS
In all the writings on the crawl stroke there has not been much reference to the interaction between the swimmer and the water. There would be such comments as "grip the water," "feel the resistance of the water" or "catch the water." What happens to the water when we swim? The answer is we don't know exactly. It's almost as if we swim in "dry water," a phrase coined by Nobel Prize physicist Richard Feynman, who headed the enquiry into the Challenger disaster.
Stroke mechanics are rarely analyzed with reference to the water and its resultant flow reactions. Some studies claim to be able to calculate the forces that swimmers develop in the water. But the trouble with these studies is that they depend on the premise of "essentially still water," and water doesn't obediently stand still while forces act upon it.
Consequently, some studies may well be flawed because they are based on the mechanics of solids rather than fluids. In dealing with a solid it is generally sufficient to measure the velocity of the body as a whole, whereas the motion of a fluid may be quite different at different points.
Swimmers and swimming coaches understand the importance of good streamlining, efficient stroke patterns, distance per stroke, and stroke frequency. But most have little understanding of the effects of their stroking actions on the water. Occasionally, one will hear a coach say, "pretend you are pulling through soft mud" or "imagine you are pulling yourself along an imaginary knotted rope, or an invisible fixed point in the water." While these descriptions may create an effective word picture in a swimmer's mind, strictly speaking, they are inappropriate because the propulsive force is not being developed against a solid or rigid resistance.
For larger 64k photo click on image. Artwork © Cecil Colwin
When a swimmer strokes efficiently, propulsion results from the water's resistance to the applied force. Water changes shape when a force is applied against it. These changes are known as deformation and they appear as flow and elasticity (caused by viscosity). A flow increases continuously under the action of an applied force, however small. A given force produces elasticity, which vanishes if the force is removed, unlike an elastic band, which snaps back.
Flow and elasticity are the two characteristics of moving water that a skilled swimmer should feel and recognize, particularly as the hand and forearm reach forward into the entry. The swimmer should actually feel the water stretch (yes, it does stretch!) as the hand meets the oncoming flow.
Unfortunately, most swimmers are unaware of this, but sensitizing exercises can quickly heighten the sensory nerve endings of the hand to become alive and sensitive to this stretching, flowing reaction of the water.
The swimmer isn't stuck in some rigid unyielding medium but creates a continuous dynamic situation within the moving flow that is constantly changing. The swimmer should try to feel how the water flows and stretches in reaction to the force impulses applied during the swimming stroke.
STROKE DRILLS
I'm not referring to drills that sensitize the hands and feet, because these sensitizing drills can be done while swimming the full stroke. They are very effective in sensitizing the sensory nerve endings of the hands and feet to the reacting flow of the water.
For larger 64k photo click on image. Artwork © Cecil Colwin
Stroke drills are intended to be effective in teaching skills. However, over the years, I 've thought long and hard about the many stroke drills that seem to be very much in vogue as a standard part of the coach's repertoire. Studying the ASCA world clinic yearbooks of recent years, I notice a growing tendency to accumulate scores and scores of different stroke drills, as if there is a certain merit in being able to produce a lot of different drills.
Back in the 1960s when I was still coaching in South Africa with our small swimming population, and cut off from the mainstream of world swimming, I developed a few stroke drills for teaching whole stroke, as well as stroke accuracy by means of part - stroke drills. This was because we didn't see many great, talented exponents of the various strokes, and neither were there many instructional films available at the time to aid the youngsters in forming concepts of fundamental movements.
In fact, when I visited the United States in 1966, after a 14 - year absence, I was surprised, when meeting Walt Schlueter for the first time, to hear that, although we were separated by a distance of 8000 miles, he and I had worked out some very similar drills, such as six - and - six - beat - kicking while lying on each side, and then changing sides by means of pull - push arm actions.
Today, my stance on the question of the value of stroke drills has become somewhat ambivalent. I've had a change of heart. In the first instance, I believe that, if carried to excess, there's a danger of the swimmers becoming very good at doing stroke drills only, and little more.
I have some doubt as to whether stroke drills have much positive transfer value in improving the overall, finished stroke. I'm not entirely convinced of their value. There are some drills that will help develop rhythm and increase flexibility, and they will also stretch the soft structures of the shoulder joints.
However, the use of drills has reached a ridiculous point, in my opinion. We see coaches who incorporate stroke drills into their practice routines because they don't want to miss out on training. They include stroke drills as a combined conditioning and stroke development training item, but I believe this to be a self - defeating approach.
I don't think it serves much purpose as a training item, and the effectiveness of these drills as such is also dubious. Some swimmers become adept at doing drills rather than improving their racing strokes. I'm being facetious, and perhaps unfair, when I say that perhaps they could even end up creating new racing events for sideways kicking drills, and the like.
To illustrate my point, take the drill where the swimmer lies on one side with one arm extended forward and the other extended back next to the thigh. The swimmer does three sideways kicks, and then pulls the forward arm back to the thigh while extending the opposite arm forward. What is the stated purpose of this drill?
It is said to develop the idea of equal movement on each side of the body. It teaches a swimmer that the body rotates on its long axis. It teaches controlled exhalation in time with the arm - stroke. It develops the pattern of the arm - stroke. It teaches that the legs also roll naturally within the body roll.
What does this drill do that can't be taught while swimming the full stroke? Now I'm not saying that coaches shouldn't have a swimmer do drills, but it all depends on what the coach is trying to teach the swimmer. A well thought - out drill may be useful if used just briefly, to illustrate a point in technique, or to establish an overall concept. But, I repeat, use it just briefly. It is a means to an end, not an end to a means.
In my view, the more talented the swimmer, the less the need to rely on drills. I'll make this concession though; for the swimmer who has a hard time learning movements, then drills may very well be the answer, but use them judiciously. Don't linger too long on these drills.
TIMING AND MOMENTUM
Regarding the drill done with sideways kicking, with arms changing over, I consider its biggest drawback or handicap to be its stop - start sequence, which could interfere with the swimmer's timing when doing the full stroke. I refer to the momentum developed by the ideal split - second timing of the entry hand with the final impulse of the opposite hand. This important timing phase is not there in the drill, and I believe that there are few drills, if any, that adequately teach this vital "connecting" phase of freestyle technique.
Momentum is a point of technique overlooked by the vast majority of coaches, and it is important. The ability to maintain momentum is probably the big differentiating factor between the great freestyle swimmers and those who are content to make speed by digging holes in the water and falling into them.
Momentum affects the amount of power that the swimmer must develop to maintain speed. Put in another way, when a stop - start action within the stroke causes a loss of speed, a greater amount of power is needed to overcome the inertia. If coaches must persist in doing stroke drills, then they must be sure that the end - effect does not inhibit the swimmer's timing and momentum.
VISUALIZATION
Visualization is nothing new. I first read about it in 1948 in the Physiology of Exercise by Morehouse and Miller. I looked up the reference again a few days ago. Part of it read like this: "Thinking about muscular performance has been shown to produce an increase in the tension of the muscles that would participate in actual performance. This phenomenon suggests that learning and perfection of skills can proceed by reading and thinking about the technique of the event. Thus a golfer during the winter season may improve his swing by studying texts written on the subject. Divers commonly repeat in their imagination the movements of a new dive before attempting to perform it off the springboard or platform."
Of course, the use of visualization has changed since then, and today's techniques incorporate relaxation, auto - suggestion, and even meditation exercises. Starting in 1966 at my swim camps in South Africa, I conducted "talk - ins" in which two or three swimmers at each session were advised in advance that they would be invited to talk for a few minutes on set topics, such as "What I think about when I'm swimming freestyle," "What I do on the day of a race," or any other topic.The purpose was to obtain feedback on a swimmer's learning and the concepts that are being formed in a swimmer's mind. This verbalization process is also an aid to visualization, if this is not too much of a contradiction in terms.
The importance of visualization has been stressed by coaches and educators over a long period of time. John Hoberman describes the work of Etienne - Jules Marey (1830 - 1904) in his book, Mortal Engines (Free Press, Toronto, 1992). According to Hoberman, "It is interesting to note that, as early as 1883, Marey had anticipated the computer - based technique that today breaks down athletic movements into discrete lines displayed on a screen for analysis in terms of their biomechanical efficiency."
Marey was the world's first visualizing physiologist and he used a technique called "photochronography" to take pictures of athletes in a series of pictures at precisely equal time intervals. According to Hoberman, Marey wrote "Language is as slow and obscure a method of expressing the duration and sequence of events as the graphic method is lucid and easy to understand. As a matter of fact, it is the only natural mode of expressing such events; and, further, the information which this kind of record conveys is that which appeals to the eyes, usually the most reliable form in which it can be expressed."
VERBAL DESCRIPTION
Visualization should be accompanied by verbal descriptions that highlight specific points in technique, and I believe it important to talk to the swimmers often, to ensure that their concentration is focused. Coaches should welcome swimmers asking questions, and not take this as a challenge to their authority.
I like swimmers to swim with their heads and not with their bellies. Therefore, before a workout starts, I make a practice of giving a brief lecturette, just a couple of minutes. I outline the purpose of the conditioning goals contained in the upcoming workout, and I also touch on one or two aspects of stroke technique that I want the swimmers to focus on, and try to accomplish.
There is a motivational purpose to this approach as well. I encourage the swimmers to try to make a little improvement each day in any or all of these three "departments": technique, physical conditioning, and, developing a positive mental approach. The sum total of these small day - to - day improvements adds up to big improvement, significant improvement, over the days, weeks, and months.
I will not hesitate to interrupt a workout and bring all the swimmers out on deck to reinforce a point that is not being observed throughout the team. I hate like mad having to do this, because I don't like to interrupt a workout, and neither do the swimmers, but I think the best way to drive a point home is to keep emphasizing it, and I try to do it with good humour. Remember, repetition is the soul of teaching
UNDERWATER OBSERVATION
I am surprised at the number of coaches I meet at clinics who say they have never videotaped their swimmers, or at least, found the opportunity to view them through underwater windows. Because of the distorting effect of light refraction on the water surface, it is difficult to obtain a clear impression of a swimmer's action from the pool deck.
I use a camcorder frequently, and over the last year, I have also used one of Marty Hull's "Snooper" underwater video cameras. The camera is attached to a hollow pole that carries a coaxial cable, and it is highly maneuverable. You can obtain views of a swimmer's stroke technique from angles that normally would be difficult to achieve, without having to go underwater to do the taping.
In this connection, I strongly advocate the type of video tape session that I am about to describe. About a year ago, with the assistance of Scott Lemley, I conducted a very interesting experiment at a clinic in Mission Viejo. We spent considerable time carefully video taping the swimmers underwater. Then we spent another hour or so in a unique three - way video - viewing and clinic session, in which the swimmers, their coaches, and I participated.
First the swimmers were asked to comment on what they saw themselves doing on the video playback. Some of them were quite surprised to see their strokes looking quite different to what they had envisaged, a surprise, I might add, that was shared by their coaches. I think that we all found this to be an informative and educational experience. I highly recommend to coaches the value of taking a few hours out of their program to organize a video session of this nature.
Here are some other methods of forming visual concepts of swimming movements. One method that Doc Counsilman recommended, I have copied over the years to good effect. Have the swimmers use face masks to observe each other under water, and have them tell each other what they are doing.
PRACTICE IN THE MIRROR
Another method that seems to have fallen into disuse - in fact, Johnny Weissmuller first advocated it many years ago - is to practice your stroke in the bedroom mirror from both the side view and the front view. A piece of string should be stretched across the mirror to indicate the surface line of the water. Practicing in front of a mirror can be of tremendous benefit in forming a visual impression that leads to greatly improved stroke technique, providing it is done intelligently and conscientiously. Coaches should recommend it to their swimmers.
While on the topic of providing the swimmer with a visual impression of the swimming stroke, I want to comment on the illustrations of the swimming strokes that appear in the bibliography of the sport. The early books on swimming tended to be sparsely illustrated. Then more books were published showing more of the stroke sequences.
Although these were an improvement, unfortunately there were still insufficient frames to adequately convey the full sequence of the movement, and the reader had to guess what parts of the stroke sequence were left out in between. Then, in the 1960s, Doc Counsilman made a big breakthrough when he perfected the use of the camera as a scientific instrument for analyzing swimming techniques. Both his educational films as well as the illustrations in his books were important aids to conceptualization of the swimming strokes.
INSTRUCTIONAL CHARTS
I think that poolside charts of the swimming stroke sequences are probably also a useful aid for swimmers to have around the deck. When youngsters casually view these materials, there is a strong likelihood that, in the process, they will subconsciously form concepts of the ideal movements shown on the charts.
By practising the stroke in the mirror, it is possible to practice the continuing movement of the stroke virtually inch by inch. This gave me an idea: why not do a series of freestyle sequence drawings showing every inch of the swimming stroke? Well, there were days when I heartily wished that I hadn't undertaken this long project!
I started by drawing one swimmer a day but eventually managed to get to a stage where I could "recruit" two, maybe three more swimmers a day on to my "paper team." It took me 50 drawings, going from left to right, to complete one stroke cycle, and thereby illustrate about one second only of swimming time. Then I realized that I had to show the other side of the body with the swimmer going from right to left, and so I ended up with about 100 drawings altogether. They represent only one of the many possible variations of swimming freestyle.
ABOUT THE ILLUSTRATIONS
I have called the series of illustrations "Every Inch a Swimmer" because I have tried to illustrate every inch of a complete stroke cycle. Note that I have not shown any water. The swimmers are "swimming" in negative space. By not "giving them water" to swim in, I am deliberately trying to make the point that instruction in stroke mechanics should always be made with reference to the flow reactions that a swimmer can expect while swimming!