The following are distillations of communications received from scientists who are investigating the properties of new swimming equipment (starting with Speedo's Aquablade). The names of the contributors will not be stated unless their express permission is granted.

From Australia

[07/02/00]

A prominent aquatics scientist and researcher in Australia has conducted preliminary evaluations of the latest bodysuits (Speedo's Fastskin and Adidas' Equipment Bodysuit) and some older vintage Speedo bodysuits. Because of the limited number of observations, and available bodysuits, the following are hypotheses suggested from this initial work.

1. If the suits are worn dry, they are buoyant and assist the swimmer. The specific gravity of the swimmer + bodysuit is less than the swimmer alone. It takes some time before the fabrics, and air pockets around the swimmer, become saturated and the buoyant assistance is lost, that is, the specific gravity matches the swimmer-alone condition. A swimmer who raced in a dry suit would have an advantage from this feature of added buoyancy.
2. When bodysuits from either manufacturer are fully saturated, there is no buoyant assistance.
3. Previous versions of the Speedo bodysuit, such as those available 18 months ago, were more buoyant than the latest versions. Among the most recent pieces of equipment, the Adidas Equipment Bodysuit is more buoyant than the Speedo Fastskin.
4. The Adidas Equipment Bodysuit creates less drag than the Speedo Fastskin, both being less resistive than the older model Speedo bodysuits.

It should be emphasized that these are preliminary findings based on accurate scientific measurements used in conjunction with competitive swimmers. They do not reflect isolated or theoretical assessments.

[07/02/00]

"In preliminary work, while swimming a standard set, the condition of wearing a full Speedo bodysuit was compared to wearing a traditional suit. Using an Aquapacer to dictate stroke rates further controlled the standard sets. For an international level backstroker and butterfly specialist, the results were the same, swimming velocity was higher when wearing the bodysuits."

[07/02/00]

A prominent hydrodynamics scientist evaluated the assistance promoted by Speedo's Aquablade suit (1996 vintage). While Speedo promotes distinct advantages and figures, most of which are theoretically derived, in practical circumstances the "old" Aquablade provided negligible assistance. The difference between advertised figures and benefits and actual amounts are currently being determined.

[From the editor: This work highlights a feature about recent marketing of swimming equipment. The figures touted by manufacturers are often theoretical, and at best, derived from equipment-alone, or fabric-alone tests. In practice, those figures are seldom approached. An example of the sales "hype" surrounding these devices was the initial emphasis on the value of sleeves. However, recently Adidas has taken to advertising only suits without sleeves and swimmers have almost universally rejected Speedo's Fastskin sleeved version. The manufacturers are rarely right and in this matter, they largely espouse inaccurate information.]

From Australia

[07/12/00]

A noted Australian sports scientist did a floatation test with a dry Speedo Fastskin bodysuit. The suit was crushed into a ball and dropped onto the pool surface. It took slightly over seven minutes to sink. [This makes one wonder just how competent were the testers and how valid were the FINA tests that yielded no buoyancy for these suits.]

Further on buoyancy, an Australian distance swimmer opined that, "The Fastskin felt good for 100 m, but after about 250 m, it suddenly felt like I was being dragged down." She is "unlikely to wear the suit at the Sydney Olympic Games."

From Europe

[07/20/00]

I was a witness of the presentation of the "Adidas" full bodysuit in Sheffield in December during the British winter nationals, and very aggressive "Speedo" presentation in Athens. Representatives of both companies [in Athens, the "scientific" aspects were presented by Jane Cappaert] did not answer a single question posed by other coaches or me. Instead, both companies promised to send me data of their "studies." So, I am still waiting mail.

From USA

[Dr. Joel Stager, Indiana University - 7/20/00]

As a result of USA Swimming's lack of vision, six months from now most small college, age group, and high school coaches will be faced with a dilemma. With miniscule budgets on the order of a few thousand dollars or so, how is it that they are to prepare their swimmers for conference/ sectional/ district/ regional/ state meets knowing that they can not afford to outfit their swimmers in these newest competitive suits? Are they to require the swimmers' parents finance this equipment? Or, are they to suggest to the swimmers that they are mentally and physically prepared to win and that the suit doesn't matter? Given the current publicity being generated...I don't think so. How do you face an athlete and know that neither talent nor preparation can overcome the 1 to 2 second advantage that a suit will confer? And, should they qualify for the next level of competition...what other choice is there? Are you going to place the athlete in a position where they can't compete because they are ill-equipped to do so? Clearly, winning is everything at the top end...why not at the bottom too? So, it isn't just about the big boys and girls... it isn't just about the "Olympic Ideal" and fair competition...it is about the sport in its entirety - from top to bottom; ethics and backbones, and the Olympic spirit. We could have taken a stand. We might have taken the high road. Swimming is not about winning or losing anymore...it is about litigation and money. Simple.

From USA

Dr. Joel Stager's Evaluation of the Impact of Bodysuits[09/02/2000]

The various bodysuit manufacturers have advertised very significant performance gains that should result from using their products. It is common to hear the figure 3% used, and in some cases, higher values are proposed (e.g., Speedo in Australia). Among the manufacturers, it is agreed that full-length bodysuits will enhance performance, despite misgivings among the swimming population about their being fitted and of certain shapes. If bodysuits, and their "high-tech" fabrics, have the obvious significant effect upon swimming performance, there should be a general improvement displayed by a swimming population when they are used in a competition.

Dr. Joel Stager, an applied physiology professor in the Department of Kinesiology at Indiana University, uniquely evaluated the effects of bodysuits on competitive performances at the US Olympic Swimming Trials held in Indianapolis in August 2000. Olympic swimming trial times from the past 25 years were used to predict the performances in the just-completed US 2000 Olympic Trials (a power curve was the line of best fit). If predicted times at the meet were similar to those recorded, then no universal performance-enhancer, such as bodysuits, existed. If there was a general improvement above that which could be reasonably expected, then one might propose that bodysuits do enhance performance in line with manufacturers' claims. A comparison of predicted and actual times would serve as an evaluation of any effect derived from bodysuits.

At the US trials, virtually all swimmers had bodysuits made available to them by various manufacturers. Astute observers estimated that 90-95% of contestants used some form of Speedo suits. One could make a compelling case that the trials were a "fair test" of the general effect of Speedo's new suits and fabrics.

Dr. Stager's work can be viewed in detail at https://www.indiana.edu/~kines/trials2000.html. It provides tables and analyses in detail. The data show that there are some events that were better and others worse than predicted (about a two to one ratio). The sizes of discrepancies were so small, that for all but two events, one could assert that performed times matched predicted times.

If one accepts the hypothesis that Dr. Stager's predicted times are "reasonable" estimates for normal swimming progression without bodysuits, or some other performance-enhancing item, some interesting conclusions can be drawn. From this reviewer's perspective, this is what was learned about bodysuits from the US trials.

Fewer women's than men's events achieved the predicted times. This is important because more women wore Speedo suits than men did, probably because they are forced to wear a torso covering.

Observations of US swimmers' behaviors were strikingly similar to those made of Australian swimmers at their trials. As the US trials progressed, swimmers began to discard the neck to ankle full suits (before the trials few swimmers would embrace sleeved-suits and so they were virtually non-existent). Breaststrokers almost completely discarded them and mostly wore traditional-cut suits in finals, although most of those suits used Speedo's new fabric. Backstrokers and butterfliers did not like below-the-knee suits and males preferred not to cover the torso. Crawlstrokers tolerated the waist to ankle covering more than in the other strokes but still were in a minority. There were few instances of the "self-tailoring" behaviors of the Australians (e.g., cutting off the lower legs, sleeves, or widening the arm apertures), probably because there was a greater variety of available suits in Indianapolis. Generally, as the trials progressed, swimmers became disenchanted with bodysuits and tended to return to styles that are more traditional. Most elite swimmers do not embrace neck-to-ankle, waist-to-ankle, and certainly sleeved suits. That does not mean that some individuals do not like the suits or do not benefit from them, or more tangentially, derive a "placebo" effect from them. The picture is slightly "muddied" by some athletes who are "paid" or "encouraged" to wear the suits.

Evidence of any performance benefit, as marketed by swimsuit manufacturers, did not exist at the US Trials. Manufacturer's claims should now be questioned. Certainly, before one of these expensive suits is purchased, much reflection is needed.

When information about these suits was presented at meetings in Athens last year, scientists in the audience asked for and were promised the supporting evidence for manufacturers' claims. Those scientists are still waiting for the evidence. The manufacturer-inspired "hype" surrounding these bodysuits has all the earmarks of a marketing ruse. Buyers are warned.

The observed lack of benefit of the bodysuits does not remove FINA's culpability for allowing them into competitions in the first place. The precedent has been set to allow external items intended to artificially alter performance into swimming races. With the Olympic Games being such a milestone in the sporting calendar, the opportunity exists for the swimming world to reverse the FINA Bureau's gaff, to return to non-performance-enhancing suits, and restore swimming as a "human-factors-only" sport. This could be achieved at the September 2000 FINA Congress in Sydney.

From Australia

Forbes Carlile and John Woolford on Bodysuit Floatation [08/02/00]

John Woolford and I conducted "floatation" experiments on two swim suits -- a women's older Speedo costume (made of NYLON/ELASTANE) and one of Speedo's full length sleeveless Fastskins. The idea was to test whether these suits floated.

Both dry suits were cast upon the surface of the Narrabeen pool. After 20 minutes, they were still floating and we decided they would never sink.

The next test was to wet them and roll them into a ball. They were then pushed under the water surface with the air squeezed out of them and both sank immediately to the bottom.

It appears that both fabrics have similar "floatation" capacities. Since they never are packed into an airless ball when used in swimming, it is reasonable to assume they do have a floatation effect on a swimmer. The advantage of the Fastskin is that it has a much greater surface area than the older, standard cut suit and therefore, will produce a greater floatation effect for a swimmer.

I do not understand how FINA can have agreed that Fastskins do not provide a floatation benefit (therefore, breaking Rule SW 10.7). It is as if FINA does not care about SW 10.7 and its essence of controlling the sport to ensure fair competition. Swimmers should be able to compete without deriving any buoyancy or speed benefit as the rule states. Clearly, they have not concerned themselves with this important aspect of the sport.

From Europe

Professor Huub Toussaint, Institute for Fundamental and Clinical Human Movement Science, Amsterdam, Netherlands [09/22/00]

Dr. Huub Toussaint compared 13 Dutch swimmers wearing their Fastskin bodysuits and wearing whatever they had worn before the bodysuits were provided. Swimmers did laps in a specialized pool, first wearing the Fastskin and then wearing the old suits. There were no significant differences between the two conditions for push-off force off the wall and average velocity across the pool.

From Brazil

Professor Horacio Vielmo of the Federal University of Rio Grande do Sul,Brazil [10/31/00]

Professor Horacio Vielmo, Department of Mechanical Engineering, Federal University of Rio Grande do Sul,Brazil (personal communication, July 20, 2000) rendered an opinion on the claims of bodysuit manufacturers. He made the following points.

1. It is misleading to extend conclusions from stable passive bodies (e.g., a swimmer or model being towed in a flume) to moving objects that feature many undulatory movements (e.g., freestyle swimmers) in stable environments (still-water swimming pools).
2. The areas of a swimmer that will only benefit from reduction in resistance are the head, neck, trunk, and upper part of the legs. On the other hand, it is desirable to increase resistance on the arms and the shank of the leg so that greater propulsion can be achieved. It would be detrimental to performance to make these surfaces "more slippery" (as occurs with Ian Thorpe's Adidas sleeved full bodysuit). [The almost universal rejection of sleeved suits by top swimmers is an empirical verification of this principle, even though Speedo produced a sleeve that was supposed to increase "grip" on the water.]
3. Another important factor to reduce drag resistance is retardation of the boundary layer stall. This can be achieved by vortex generators, which might be rough surfaces, such as the various roughnesses used on the hulls of sailboats and yachts. It is possible to cover the skin with a fabric but if it is not well designed, it could act as a porous medium, and actually magnify drag. [Most distance swimmers have realized this and feel that at least the Speedo suits act like "drag suits" part way through a race. That is okay for the arms, but not for the trunk or upper legs.]
4. Suits could enhance buoyancy by using a material less dense than water and by trapping air.
5. If the suit is shaped properly and tight enough, a bodysuit might improve the conformation of the body, diminishing cavities and natural surface undulations.
6. It is not known whether the pressure on muscles from restricting suits would enhance or diminish performance.
7. For treating a complex scientific problem such as swimming, which involves fluid flow in transient form, with laminar and turbulent regions in a complex geometry, theoretical approaches or isolated minor testing are not enough to understand the phenomenon. Only proper experimentation will answer the real questions [and these have yet to be performed by manufacturers or scientists].

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