Selasa, 25 Maret 2008

Speedo's LZR swimsuit

The Speedo LZR racer: feedback on a developing debate, and the value of technique

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Thanks to all who have commented on yesterday's post, which focused mainly on the newly developed swimsuit by Speedo, the LZR Racer. This suit is making waves in the swimming world, since it has been worn for 9 out of 9 world records in the pool this year! Some coaches believe the issue of fairness needs to be debated, with calls for ethics debates around it.

Your comments have been very insightful, none more so than Jamie's, as he wrote in response to yesterday's post. I had not even thought of rowing as an example of a sport with similar equipment "advantages" possible. But his email gives a great example:
In rowing we also have an interaction with water and this aspect of the technique/training generally has a bigger impact than the physiology. FISA (our international federation) dealt with similar issues as swimming is going through in the 70's and 80's when some countries started using riblets running the length of the boats hull and also applied what was called "fish slime" which changed the properties of the hull/water interface and made significant difference in time (10 sec in a 6 min race).

The riblets were banned because of the expense as they were very easily damaged and had to be replaced often and the "fish slime" was banned as it was deemed a pollutant in the water

Our rules now say the following:
Bye-Law to Rule 31 - Boats and Equipment

1.4 No substances or structures (including riblets) capable of modifying the natural properties of water or of the boundary layer of the hull/water interface shall be used.

It would seem that the claims of Speedo/NASA indicate that with the new suits this boundary layer between the body/suit and the water is definitely modified. Whether FINA consider this unfair or not will be the deciding factor in the debate.
Input from an expert on swimming hydrodynamics

In addition, as I began writing the post yesterday, I contacted Prof Raul Arellano, who is based at the University of Granada in Spain. Arellano has spent years studying fluid movements during swimming, and has published numerous papers looking at propulsion and biomechanics of swimming, so he contributes to the specific debate around swimming with a far more experienced and educated eye than I can!

And his input is very interesting. I've pasted some of his response below, with my comments immediately following them.
The problem with the new swimsuits is that they improve the body shape much more than skin friction. And this improvement is very individual... the percentage improvement depends on the person's body shape. I have observed a master swimmer with a lot of fat around her abdominals reduce her time in 100m butterfly by 6 seconds to break the Master's world record. The changes in the body shape underwater using a smaller size full body swimsuit were clearly evident (the fat position was fixed and the perimeter reduced).
In yesterday's post, and in the news reports, a great deal was made of the reduced drag as a result of the LZR suit being seamless and consisting of new materials tested by NASA. This insight suggests that in fact, the suit's ability to reduce friction and drag may be minor compared to the improvement in body shape as a result of wearing the swimsuit. Is this analogous to the compression garments now being touted for team sports and explosive sport in particular? That came up in one of the comments to the previous post - of course, the effect would be substantially larger in the water, and the mechanism is different, but it's still intriguing.

In addition, Prof Arellano noted the following:
These changes [in performance] are much smaller in well trained top athletes, but enough to improve the performance some tenths of second. But you need to add some more things related to HiTech doping; for example, is the use of biomechanics HighTech doping? This tool is far less accessible than a swimsuit and so very few swimming teams use this kind of enhancing tool. We have observed changes in the start technique, changes in the underwater phase of the start and turns, changes in the stroke synchronization, changes in the body position, and so on.

In our experience testing top level swimmers at the end of one feedback and training workout to improve the swimming start, we obtained improvements of half a second in the 10m start time. Is this improvement doping? You can see the videos of Olympic champions during Munich 1972 or Seoul 1998 and you can observe very bad start and turn techniques, these changes can affect to the top performers much more than the use of new swimsuits.
For example, if you observe Michael Phelps' start and turns, he can obtain more than two seconds' advantage in 400m IM. The rest of competitors and their coaches can use the same turn technique as Phelps but they don't ? Why? ...Who knows?
Fascinating insight - what is being referred to here is that we may dwell on the swimsuit and its potential advantages, but there may be even bigger advantages gained through the use of biomechanical studies/methods and training to improve the technique of the swimmer, not during the stroke only, but also the start and turns. Of course, the debate still exists that two swimmers may be very closely matched in terms of physiology, biomechanics and technique, but the one in the faster swimsuit will win. And it is unfortunately a reality that not all swimmers will have equal access to the "possibly faster" swimsuit. As I mentioned yesterday, sponsorship agreements often dictate that swimmer cannot wear a Speedo, and that means the playing field may not necessarily be equal. Many individuals (including Alain Bernard, world record holder) have obatined individual sponsorships that opposed that of their federation (Bernard is a Speedo LZR man, the French team is sponsorsed by Arena). One thing that is for sure is that I would hate to be the sole swimmer not wearing the suit that is possibly worth one second in my Olympic final...

Why leave any stone unturned?

In any event, one thing that never ceases to amaze me is that there are, as Prof Arellano has pointed out, world class athletes who miss out on opportunities for improvement that they could use to gain seconds on their performance. And who knows why they would not? The case of the Speedo LZR once again highlights the fact that there are people who naturally embrace technology and innovation, and some who do not (or cannot, as the case may be). I know if I was swimming, I'd be embracing every single opportunity for improvement, even if it was unproven!

And then finally, Prof Arellano has noted the following with regards to Alain Bernard, the French swimmer who recently broke the 50m and 100m freestyle records. This is in the context of talking about the recently set world records and whether they are solely due to the new swimsuit:
At least I can observe clearly some technical aspects improved by some record holders before their impressive performances. Bernard, for his 50m and 100 m World record, significantly improved his start technique, getting the 1st place immediately from the start (this point improved more than half a second [from his France record in 100m free performed last season in France]. This is critical to be winner in the 50m or 100m events, where the waves generated by the rest of competitors can affect you in a magnitude (increasing your total drag) that is impossible to overcome keep up with the more quicker starters. You do not have enough energy to surpass the increased wave drag.
Interesting then that training, even in the day and age of superior technology can still make such a large difference. I recall that Roland Schoeman, South Africa's best swimmer at the Athens Olympics, stood out for his incredibly fast starts, that often had him a body length clear within the first 30 m of a 100m freestyle event. I find it astonishing that the other seven guys in the Olympic Final could be that comprehensively "outstarted", considering the importance of that aspect of the race. There are analogies and comparisons with many sports; I can think of a few cases where athletes have made very basic errors in preparation that would be easily resolved through simply listening.

And so like Prof Arellano, I have no answer for why more athletes would not develop these obviously crucial areas a little more than they have, and work on technique when it's apparently available to those who really want it. I suspect that part of the problem is that elite atheltes (and their management team) become quite insulated from the "voices" beneath them. And so they fail to hear or listen to anyone but the select few in direct contact with them. Thus, they often won't even perceive the possible benefits they might gain simply by listening to others.

Regardless, the swimsuit debate rages on, with a discussion between FINA and Speedo scheduled for the World Short Course Championships in a few weeks. Difficult to see how anything can be done now, unless they're prepared to scrap the world records set so far this year?

Looking ahead to the rest of the week...

That's it for the swimming for now - thanks to all who have commented and written in, feel free to throw your hat in the ring on this latest one.

But speaking of technique, it's back to running tomorrow, when I'll take a look at running technique, and specifically, the landing of the foot. Should you land on the forefoot? Or is heel striking the better option? We'll have a crack at that then.

As for the rest of the week, a big event on the weekend - World Cross Country championships in Edinburgh. The first big Championship clash of the year between Kenenisa Bekele and Zersenay Tadese. I'm sure that will warrant a post or two!

But for tomorrow, it's foot strike in running. Join us then!

Ross

For more discussion and analysis of the Speedo Swimsuit issue, click on the following links:
  1. The Speedo LZR Racer: Introduction and debate: Does Speedo's "supersuit" make world records irrelevant? The line between "tech-doping" and innovation
  2. Speedo's LZR: The role of swimming technique in progress - the suit or the style?
  3. The swimsuit wars begin: Arena enters the fray, and what goes into suit design
  4. Adidas launches its swimsuit: Are we watching swimmers or "human-powered boats"?
  5. Arena attack Speedo: Arena seeks to have the Speedo LZR Racer banned
  6. Arena's threat of legal action: Suddenly the integrity of the sport is at stake
  7. World records disappear by EIGHT seconds: The swimming crisis

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